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Observing a sora in its natural habitat is well worth the effort. Patient (and lucky) observers may catch a glimpse of this wetland inhabitant throughout the spring and early summer, at most any heavily vegetated wetland. Large, remote wetlands hosting dense stands of cattail (Typha latifolia) and other tall wetland plants often hold several pairs of breeding soras. Recorded playbacks (available at most birding stores) of soras or any other rail will virtually guarantee a response from a curious sora, although a whistled facsimile may also suffice (pers. obs.).
Perception Channels: visual ; tactile ; acoustic ; chemical
Numbers have declined across the sora's range, coinciding with loss of wetland habitat, however the species is still abundant (Kaufman, 1996). The sora is an unprotected species, and is considered to be a migratory game bird (U. S. Fish and Wildlife Service, 2000), although it is not often hunted.
US Migratory Bird Act: protected
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
The sora is considered a game bird under the Migratory bird treaty act (U.S. Fish and Wildlife Service, 2000) and may be hunted for food.
Viewing a sora in its natural habitat is a well won prize for an avid birder's effort.
Diet consists mainly of seeds, insects and snails. Seeds are obtained from sedges (Carex spp.), grasses (Calamagrostis spp., Bromus spp., Scoacloa spp., Poa spp., etc) or other wetland plants. Snails and insects are picked from ground surface, or by probing soft mud and vegetation with its bill.
(Kaufman, 1996)
Breeding range:
The sora (Porzana carolina) occupies much of temperate North America, ranging (in the west) as far north as the Northwest Territories, to the southern extremes of Arizona and New Mexico. The breeding range of P. carolina narrows in the east, occurring from Canada's Maritime provinces south to Maryland, USA.
Overwintering range:
As wetlands freeze in the breeding range of P. carolina, this species moves south to overwinter, occupying the southern United States from Arizona to Florida, and also throughout Mexico. In addition, many individuals migrate across the Gulf of Mexico and Caribbean Sea to overwinter in South America.
The coastline of California hosts P. carolina year round.
(Kaufman, 1996)
Biogeographic Regions: nearctic (Native )
The sora occupies a freshwater wetland habitat throughout its range; it also uses salt marshes while overwintering. The preferred habitat provides considerable cover for breeding soras, and consists mostly of freshwater wetlands with stands of cattail, sedges, and other tall wetland plants (Kaufman, 1996).
Sexually monomorphic. Length 20-30 cm (8-10"). In its breeding plumage, the sora's throat and face are black, with a short, yellowish bill. The breast and nape of neck are gray. The back is mottled brown and the belly displays black and white barring.
Immature and non-breeding plumages are plainer and buff colored with no black on throat or face. While in this plumage, the throat is white and the breast is light brown. The legs of P. carolina are yellowish green. The tail is usually held erect while walking and flying.
(Godfrey, 1986; Semenchuk, 1992)
The body of a sora is suited for the marshy habitat that they occupy. Lateral compression of the body offers easy travel through dense vegetation. The sora possesses short, round wings which offer seemingly weak, but highly maneuverable flight through tangled vegetation. Strong legs, with long slender toes on provide P. carolina with a strong walking and running ability amongst tangled wetland vegetation. Although this species prefers walking to flying, its long distance capabilities are evident in its migration, often crossing the Gulf of Mexico and the Caribean.
(Semenchuk, 1992; Kaufman, 1996)
Other Physical Features: endothermic ; bilateral symmetry
Nests are woven into a shallow basket from dead emergent wetland vegetation, and attached to stalks of dense, live vegetation. Nests are generally placed over or adjacent to water, occasionally occurring in dry environments such as willows or grassy habitat near water's edge. (Godfrey, 1986).
The average clutch size ranges from 10-12 (sometimes 6-18) brown, spotted eggs, occasionally laid in two layers to accommodate such large numbers in a relatively small nest. Incubation by both parents lasts from 18-20 days, and is initiated with the laying of the first few eggs (Kaufman, 1996).
Young hatch asynchronously due to incremental stages of incubation. Precocial downy young may be cared for by one parent, as the other parent incubates remaining eggs. Young soras leave the nest shortly after hatching, and mainly forage themselves, having been taught by a parent (Salt and Salt, 1976). At 21-25 days young soras fledge and gain independence from their parents' care.
(Kaufman, 1996)
Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous
A medium-sized (8-9 ¾ inches) rail, the Sora is most easily identified by its mottled brown back, gray neck, and black face and throat. Other field marks include a bright yellow bill, brown striped flanks, and a short tail. Male and female Soras are similar to one another in all seasons. The Sora breeds across much of Canada and the northern half of the United States. In the west, this species’ range extends as far south as central Arizona, while in the east this species breeds locally as far south as Virginia. During the winter, Soras may be found along the Pacific coast south of Oregon, along the Atlantic and Gulf coasts south of Delaware, and in the tropics as far south as northern South America. Soras breed in shallow freshwater wetland habitats. In winter, this species is less tied to freshwater, and may be found in ponds or small lakes, freshwater or saltwater marshes, flooded grasslands, and mangrove wetlands. Soras primarily eat a variety of plant and animal foods, including seeds and small aquatic invertebrates. In appropriate habitat, Soras may be seen wading in shallow water while foraging for food on the surface. If these birds are more hidden, perhaps beneath tall marsh grasses, it may still be possible to hear their call, a high tooting “ker-wee?” repeated many times in succession. Soras are primarily active during the day, although they may be heard calling at night.
A medium-sized (8-9 ¾ inches) rail, the Sora is most easily identified by its mottled brown back, gray neck, and black face and throat. Other field marks include a bright yellow bill, brown striped flanks, and a short tail. Male and female Soras are similar to one another in all seasons. The Sora breeds across much of Canada and the northern half of the United States. In the west, this species’ range extends as far south as central Arizona, while in the east this species breeds locally as far south as Virginia. During the winter, Soras may be found along the Pacific coast south of Oregon, along the Atlantic and Gulf coasts south of Delaware, and in the tropics as far south as northern South America. Soras breed in shallow freshwater wetland habitats. In winter, this species is less tied to freshwater, and may be found in ponds or small lakes, freshwater or saltwater marshes, flooded grasslands, and mangrove wetlands. Soras primarily eat a variety of plant and animal foods, including seeds and small aquatic invertebrates. In appropriate habitat, Soras may be seen wading in shallow water while foraging for food on the surface. If these birds are more hidden, perhaps beneath tall marsh grasses, it may still be possible to hear their call, a high tooting “ker-wee?” repeated many times in succession. Soras are primarily active during the day, although they may be heard calling at night.
Soras are commonly reported in plant communities dominated by the species listed below:
Cattails (Typha spp.) [8,24,28,34,36,38,51]
Sedges (Carex spp.) [24,27,36,38,51,54]
Bulrushes (Scirpus spp.) [8,24,27,38,40]
Smartweeds (Polygonum spp.) [36,40,54]
Rushes (Juncus spp.) [36,54]
Rice cutgrass (Leersia oryzoides) [40,50]
Barnyard grasses (Echinochloa spp.) [50,54]
Although soras use wetland and marsh habitats almost exclusively throughout the year, they may be found in other habitats.
Outside of wetlands, soras are most often reported in cultivated areas during migration or in the postbreeding period. For instance, a sora was observed 3 miles (5 km) from marshland in a cultivated field in Iowa in the middle of August [25]. A male sora was observed less than 1,000 feet (300 m) from a large wetland in a soybean (Glycine max) field in northwestern Iowa during the postbreeding period [26]. From early June to mid-July, soras were observed on farms in Saskatchewan sown mainly with wheat (Triticum aestivum) [57]. In addition, Ribic [51] cites 2 sources for the occurrence of soras in cranberry (Vaccinium macrocarpon) bogs.
Soras have also been reported in flooded wooded areas [19,34]. In western New York, soras occurred during the breeding season on a study site where 26% of the area was categorized as "flooded timber," and 5% was classed as "scrub/shrub marsh" [34]. In eastern and central Maine, an average of 2.1 soras was observed in wooded swamps per 100 hours of observation during the breeding season [19]. On a nonbreeding (August-April) site in southwestern Arizona, soras were found to use a "mixed shrub community" more than expected based on its availability [8]. Species composition of these areas was not described.
Soras were observed at low abundances on a site with Douglas-fir (Pseudotsuga menziesii), ponderosa pine (Pinus ponderosa), and trembling aspen (Populus tremuloides) in British Columbia. Details regarding the circumstances of these observations, such as distance to the nearest wetland or the degree of attachment to this site, were not included [41].Soras may be more vulnerable to direct fire impacts than many birds. In addition to their terrestrial habits, adult sora are flightless for a period after breeding while they molt [2]. However, 2 prescribed fires in the coastal prairie of Texas during February and March did not result in any rail (Rallidae) mortality. Rails, including soras, were thought to have survived by seeking shelter under damp vegetation. The authors suggest burning later in the spring or in the summer, when amounts of standing water are reduced, could lead to a larger direct impact [22]. See the Research Paper by Grace and others [22] for details of this study. In addition to season, the scale of burning can also influence rail survival. Patchy prescribed burns in Florida in August left many 0.1- to 2-acre (0.04-0.8 ha) unburned areas, where black rails (Laterallus jamaicensis) were observed immediately after burning. In contrast, widespread prescribed fires that burned 90% of 2,400 acres (970 ha) in January resulted in direct bird mortality, possibly due to burning of the areas birds used for shelter. The authors strongly encourage the incorporation of wildlife escape areas into burning plans [31].
Although there were no data directly investigating sora nest mortality due to fire as of 2006, literature reviews have used fire characteristics and life history of species to speculate on possible effects of fire on nesting success and bird populations [37,52]. Since soras nest on the ground, even low-severity fires could have negative impacts on eggs and nestlings. Young nestlings are less mobile than adults [28], which could limit their options when seeking shelter from fire. The possibility of sora renesting may reduce the direct effects of a fire on sora recruitment [37,52]. Nests impacted early enough in the breeding season could be compensated for by later nesting attempts. However, since soras typically rear only 1 brood per year (see Timing of Major Life History Events), fires in the mid- to late-breeding season may have a larger detrimental effect on sora recruitment. In addition to the timing and uniformity of the burn, other fire characteristics such as the fire severity and frequency are likely to influence the degree to which fire directly impacts sora reproduction [37].
Despite the lack of direct impact of fire on rails during prescribed fires in the coastal prairie of Texas, indirect mortality of Virginia rails and yellow rails (Coturnicops noveboracensis) due to fire-related predation was observed [22].
According to field guides, soras occur throughout most of North America [10,44]. Soras breed from Nova Scotia northeast to southern Yukon and Northwest Territories, south to California, Arizona, and New Mexico and northeast to Pennsylvania and New England. Sora wintering grounds include the northern portions of South America, including Ecuador, Columbia, and Venezuela, north through Central America and Mexico to southern California in the West and coastal regions of the Southeast. From southern Kansas south to northern and eastern Texas and east through the inland areas of the southeastern United States, soras are typically only observed during migration in the spring and fall. In a few areas of the western United States, including central California and areas of Arizona and New Mexico, soras may occur year round [10,44]. A general map of the sora's distribution can be found at Cornell's All About Birds website.
The following lists are speculative and are based on the habitat characteristics and species composition of communities soras are known to occupy during migration and on breeding and wintering grounds. There is not conclusive evidence that soras occur in all the habitat types listed, and some community types, especially those used rarely, may have been omitted.
Soras eat a wide range of foods. Animals that are commonly reported as sora food items include snails (Gastropoda), crustaceans (Crustacea), spiders (Araneae), and insects (Insecta), mainly beetles (Coleoptera), grasshoppers (Orthoptera), flies (Diptera), and dragonflies (Odonata) [25,39,40,53]. Soras often eat the seeds of plants, such as smartweeds, bulrushes, sedges, and barnyard grasses [2,25,39,40,53]. Seeds of annual wildrice (Zizania aquatica) and rice cutgrass are eaten by soras in the eastern United States [39,40]. A literature review lists crowngrass (Paspalum spp.) and rice (Oryza sativa) as relatively important food sources for soras in the Southeast. Plants comprising <5% of the sora's diet are also listed and include spikerushes (Eleocharis spp.), duckweeds (Lemnaceae), pondweeds (Potamogeton spp.), panicgrasses (Panicum spp.), cordgrasses (Spartina spp.), and saltgrass (Distichlis spicata) [39].
According to a literature review, soras eat more plant food in fall and winter (68%-69%) than in spring and summer (40%) [39]. Plant material such as hairy crabgrass (Digitaria sanguinalis), fall panicgrass (Panicum dichotomiflorum), and bristlegrass (Setaria spp.) occurred at substantially higher frequencies and in much larger volumes in sora esophagi collected in southeastern Missouri during fall migration than those collected in spring. In addition, animals comprised a larger volume of the spring diet than the fall diet. The volume of animal material in esophagi collected in spring was predominantly composed of adult beetles and snails from the Physidae family [53].
Very little information is available on the effects of fire on soras. The available information is limited in several respects including temporal and spatial scale. There is also a lack of information regarding the effects of various site and fire characteristics on soras' response to burning. In addition, as of 2006 there were no comparisons of sora demographic data from burned and unburned areas.
Soras may leave burned areas soon after fire. Within 4 days of a prescribed burn on the coastal prairie of Texas, a sora left the area, possibly due to unsuitable habitat [22]. Immediately after patchy prescribed burns in Florida, black rails were observed in unburned areas [31]. In addition, a review states that the lack of cover available after fire results in rails leaving burned areas [7].
Soras have been reported in recently burned areas. For instance, 2 soras were observed on the shoreline of a man-made pond in northern Florida within 5 months of a winter prescribed burn. Soras were not observed in the unburned portion of the shoreline [61]. On a Colorado site where 90% of the area had been burned under prescription in previous winters, a large number of rails, most likely Virginia rails and soras, was observed during spring migration in remaining and new (<12 inches (30 cm)) narrow-leaved cattail (Typha angustifolia) vegetation [23].
There is limited evidence that soras may not be greatly affected by fire. In a study on Matagorda Island, Texas, members of the Rallidae family did not exhibit significant (p>0.24) responses to winter or summer prescribed burns either 6 to 10 months or 18 to 22 months after fire [60]. In the Chenier Plain in southwestern Louisiana, winter prescribed burning in habitats of varying management history and salinity did not have substantial effects on soras. The following table shows the average number of soras detected per survey in each of the habitats in the 3 springs (April-June) following treatment [17]
YearBurned
Unburned
Impounded Not impounded Impounded Not impounded Brackish Intermediate Brackish Saline Brackish Intermediate Brackish Saline 1996 0.1 0.0 0.1 0.2 0.0 0.0 0.1 0.1 1997 0.0 0.1 0.1 0.0 0.0 0.1 0.1 0.0 1998 0.0 0.1 0.2 0.0 0.1 0.2 0.1 0.1Since emergent vegetation provides cover and food for soras, the response this vegetation has to fire is likely to have a large influence on the effect a fire will have on soras. Wetlands typically recover quickly after fire. A review summarizes a report of vegetation in a Florida freshwater marsh nearing complete recovery 6 months after prescribed burning [62]. Vegetation structure on a site in southwestern Louisiana returned to prefire conditions within 1 year of a winter prescribed burn [17]. In Glacier National Park, Montana, sedge meadows were mostly revegetated the year following the 1988 Red Bench Wildfire [63]. In South Dakota, screening cover 1 growing season after spring prescribed burns was not significantly (p>0.05) different from cover before the treatment [55]. On a burned shoreline in Florida, frequency of maidencane (Panicum hemitomon) and swamp smartweed (Polygonum hydropiperoides) was similar on burned and unburned sites the May following a winter prescribed burn. In addition, burning resulted in higher productivity of the wet-prairie vegetation [61].
Somewhat longer recovery times have been reported. In cordgrass/crowngrass habitat on Matagorda Island, vegetation attributes recovered to prefire levels by 18 to 22 months after spring and fall prescribed burns [60]. After a wildfire in a Texas tidal flat, community structure did not recover for 16 months, vegetative cover did not met or exceed prefire cover for 19 months, and live and litter biomass had not reached prefire levels by postfire month 26 [33].
The response of marsh vegetation to fire is influenced by several factors including fire characteristics such as severity and season of burning, and site conditions such as salinity and hydrologic factors.
High-severity fires that burn into the organic layer are likely to result in long recovery times. Areas of sedge meadows of Glacier National Park where the peat had been completely consumed in the Red Bench Wildfire recovered more slowly than areas where rhizomes and roots had survived [63]. Rhizomatous plant species are likely to survive fires that do not burn deep into the organic ground layer, resulting in quick recovery of vegetation after fire [17,63]. A review summarizes the effect of fire severity on marshes, including references to severe fires consuming peat and resulting in long vegetation recovery times and the creation of open water [48].
Season of burn can affect the response of marsh vegetation to fire. There was no significant (p>0.05) difference in screening cover a growing season after spring prescribed burning in a narrow-leaved- and common cattail (Typha latifolia)-dominated wetland of South Dakota. However, sites that were burned in fall had significantly (p<0.05) less cover 1 growing season after fire than before the burn [55].
Site characteristics also influence vegetation response to fire. Results of a study on a marsh in Florida suggest that fire can have variable effects that are related to hydrology and nutrients [30]. Researchers investigating prescribed fires in southwest Louisiana note the probable influence of several site factors such as plant community composition before the burn, water depth, and salinity [17]. A review summarized the role of salinity and other preexisting site conditions on postfire succession in eastern marshes [62].
Fire ecology: According to a review, wetlands tend to burn during drought, and small wetlands and marshes can burn at frequencies similar to adjacent vegetation [11]. For information regarding presettlement FIRE REGIMES of marshes, peatlands, and swamps of the southeast see [16]. A review discusses succession in eastern marshes [62].
FIRE REGIMES: The following table provides fire return intervals for plant communities and ecosystems where sora is important. Find fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find FIRE REGIMES".
Community or ecosystem Dominant species Fire return interval range (years) bluestem-Sacahuista prairie Andropogon littoralis-Spartina spartinae <10 northern cordgrass prairie Distichlis spicata-Spartina spp. 1-3 [49] Everglades Mariscus jamaicensis <10 [43] mountain grasslands Pseudoroegneria spicata 3-40 (x=10) [3,4] tule marshes Scirpus and/or Typha spp. <35 southern cordgrass prairie Spartina alterniflora 1-3 [49]Sora populations in the United States have been declining. Breeding bird survey data show a 3.3% annual decline in sora populations from 1966 to 1991. Although populations in Canada were stable from 1982 to 1991, sora populations in the United States declined significantly (p<0.01) during the same period, at an average rate of 8.5% annually. Population declines in central North America were the most severe [9]. Reviews also note sora declines [12,50].
Use of playback calls has been shown to increase detection of soras [20,34,51]. Use of playback calls in developing monitoring programs for soras has been investigated by [21,35,38].
Grazing is likely to negatively impact sora habitat. In southeastern Oregon, sora did not occur on a site where grazing was recently (0-2 years) excluded, but did occur on a nearby site where grazing had been excluded for 30 years. Soras occurred after 3 years of no grazing on the previous site [13]. Management recommendations based on expert opinion suggest that sora be considered when developing a grazing plan, as grazing consistently has a negative impact on wetland habitats [65].Water and emergent vegetation are important sora habitat characteristics.
Water: Soras use areas with a wide range of water depths. They are often observed in water less than 1 foot (30 cm) deep [24,38,50,54], although the average water depth of sora heavy-use areas in Arizona was 20 inches (52.2 cm) [8]. In northwestern Iowa, average water depth in sora territories was 15 inches (38.4 cm), which was significantly (p<0.025) more shallow than water depths at random locations in the marsh [27]. Sora nesting sites occurred in shallower water than random sites in western New York [34]. Average water depths reported at nest sites range from 4 inches (10.7 cm) for 4 sora nests in Colorado [23] to nearly 10 inches (24.2 cm) for sora nests in western New York [34]. In areas of deep water, soras typically wade on mats of floating vegetation [23,26].
Water level fluctuations may result in nest abandonment. For example, at a site in Colorado where water level increased more than 8 inches (20 cm), a sora nest with 7 eggs was abandoned [24]. In Alberta, soras nested in more vegetation types during a drought year, most likely due to substantially reduced water levels in the vegetation used the previous year [36].
Soras use areas with shallower water in fall than in spring [8,50,54]. It is likely that these seasonal differences reflect variation in availability of different habitats rather than habitat preference changing seasonally [54]. The mean water depths of sora locations in northeastern Missouri during spring and fall are shown in the table below [50].
Mean water depth in mm (range) Spring (n=60) 181 (27-433) Fall (n=68) 148 (54-301)Soras typically avoid open water. There is a significant (p≤0.05) negative relationship between area of open water and sora use of wetlands in Maine [19] and sora relative abundance in Saskatchewan [57]. In western New York, sora nesting sites had a lower percentage of open water than random sites [34], and in Arizona soras used open water areas less than their availability [8].
Emergent vegetation: Sora nesting sites had larger percentage of emergent vegetation than random sites in marshes of western New York [34]. Sora numbers in wetlands of northeastern North Dakota were significantly (p<0.05) positively correlated (r=0.45) with hectares of live emergent vegetation [32]. In east and central Maine, wetlands used by soras had significantly (p=0.01) greater area of emergent vegetation than unused wetlands [19].
Density of emergent vegetation in sora habitat varies. Reported density of emergent vegetation ranges from an average of 121.9 stems/m² in sora territories in northwestern Iowa [27] to 333 stems/m² on sites in northeastern Missouri used during fall migration [50]. In western New York, cover was greater than 70% at 95% of sora nests. In addition, nesting sites had more horizontal cover at 20 inches (0.5 m) above water level than random sites [34]. However, average stem density on sora territories was not significantly (p>0.05) different from random sites in northwestern Iowa [27].
Height of emergent vegetation in sora habitat also varies. Height of vegetation reported in the literature ranged from 8 to 11 inches (20-30 cm) in the spring after a winter disturbance in northwestern Iowa [27] to 84 inches (213 cm) in areas heavily used by soras in Arizona [8]. In marshes of western New York, average vegetation height at sora nesting sites was shorter than at random locations [34]. However, the average height of emergent vegetation in sora territories in northeastern Iowa was not significantly (p>0.05) different from the height of vegetation in random plots [27].
In Arizona, both cover and height of vegetation used by soras varied with seasons. Conway suggested the differences likely reflected the varied diet of the sora [8]. The availability of habitat in different seasons is another possible source of seasonal differences in sora habitat [54].
Extent of woody vegetation surrounding South Dakota wetlands was not significantly (p=0.6) associated with sora occurrence [45]. However, in marshes of western New York, there was a significant (p=0.041) negative relationship between percent flooded timber on a site and sora relative abundance [34].
Soras may prefer some cover types. In Arizona, 65.3% of sora use was in southern cattail (Typha domingensis), although it comprised only 16.5% of the vegetation. Bulrushes and a mixed-shrub community were also used more than their availability, while saltcedar (Tamarix chinensis) and arrowweed (Pluchea sericea) were avoided [8]. A literature review notes sora avoidance of purple loosestrife (Lythrum salicaria)-dominated sites [6]. In east and central Maine, wetlands used by soras had significantly (p=0.05) more ericaceous vegetation, such as leatherleaves (Chamaedaphne spp.), sweetgales (Myrica spp.), and laurels (Kalmia spp.) [19]. In marshes of northwestern Iowa, broadleaf arrowhead (Sagittaria latifolia) occurred in sora territories significantly (p<0.01) more often than at random sites. Johnson and Dinsmore [27] imply that this likely results from both species preferring similar site conditions. In May and June in Wisconsin, soras were detected significantly (p<0.025) more often in cattail (Typha spp.) survey areas than in sedge areas [51]. However, in southeastern Wisconsin during the breeding season, there was no significant (p=0.943) difference in sora densities between habitats comprised predominantly of cattail, sedge, or bulrush [38]. In addition, soras' use of glaucous cattail (Typha à glauca), broadfruit bur-reed (Sparganium eurycarpum), sedge, river bulrush (Schoenoplectus fluviatilis), and hardstem bulrush (S. acutus var. acutus) habitats in marshes of northwestern Iowa generally reflected availability of these habitats [27].
Seasonal differences in sora habitat use have been reported. In northeastern Missouri in spring, the likelihood of detecting sora in robust emergents, such as cattail (Typha spp.) and longroot smartweed (Polygonum amphibium var. emersum), was over 6 times that of detecting soras in these areas in fall. However, availability of habitats during various times of the year was not addressed [50]. In a study performed in southeastern Missouri, plant species used by sora during spring and fall migration differed significantly (p=0.005). However, the author qualifies this finding with his observation of major seasonal differences in vegetation availability [54].
Temperature: Temperature may also influence sora abundance. In Colorado, average April temperature was significantly (p<0.01) negatively correlated (r= -0.94) with sora abundance. On sites that had average April temperatures ≤42 °F (5.6 °C), soras were more abundant than closely related Virginia rails (Rallus limicola), while on warmer sites the sora to Virginia rail ratio declined [24].
Densities: Sora densities reported in literature reviews vary from to 12 soras/acre in Colorado [12] to 0.47 pair/ha in Indiana [42]. An average of 1.3 soras/ha responded to calls across sites in Colorado [24]. A similar density of soras was found in southeastern Wisconsin [38]. In Iowa, average density over 2 years and several marsh habitats was 1.3 pairs/ha [27].
Effects of spatial arrangement/area: Landscape factors, such as marsh area, habitat edges within marshes, and the number of marshes in a region may influence soras.
Although soras occur in marshes of all sizes, they may occur at higher densities in intermediate-sized marshes. Soras were significantly (p≤0.01) positively related with total wetland area and perimeter area of surface water in east and central Maine [19] and were significantly (p<0.05) positively related to area of wetlands in Saskatchewan [57]. In Maine, soras used 10% of 2.5-acre (1 ha) wetlands, 40% to 50% of wetlands from 2.5 to 50 acres (1-20 ha) in size, and 20% of wetlands larger than 50 acres (20 ha). [19]. In western New York, soras were significantly (p=0.007) more abundant in marshes from 100 to 250 acres (41-100 ha) in size than in smaller (<100 acres (41 ha)) or larger (250-380 acres (101-155 ha)) marshes. In addition, sora nests were detected more often in the 100- to 250-acre (41-100 ha) marshes [34].
Soras also seem to prefer edge habitats. Breeding sora density was significantly (p<0.001) correlated (r=0.62) with the perimeter:area ratio of northwestern Iowa marshes. The distance from the center of sora territories to a habitat edge was also significantly (p<0.005) less than from the center of Virginia rail territories [27]. In Arizona, habitat edges were closer to sora heavy use areas than random sites [8].
Wetland dynamics at a large scale can affect soras. Indices of sora population at 3 "levels of response" were significantly (p<0.01) correlated (r≥0.70) with the number of ponds present in the prairie pothole region of North Dakota in May [47].
(key to state/province abbreviations)
UNITED STATES
CANADA
MEXICO
Migration: Soras' northern migration occurs in spring, primarily in April and May. For instance, in east-central Kansas significantly (p<0.05) more soras were detected from 24 April to 7 May than the 2-week periods before or after [64]. In southeast Missouri, soras were observed from 25 March to 6 May [54]. Soras were 1st detected in April to early May in Colorado [24], Iowa, and Minnesota [28]. In a summary of the 1st detections of soras in Minnesota, Manitoba, and Saskatchewan, all occurred in April [46].
Soras depart their breeding grounds as early as July and as late as October. Soras were observed returning to wintering grounds in Arizona as early as late July [8]. Although local movements may obscure migration occurring in July, most migration occurred in August and September in Colorado [23]. In northern Ohio, sora abundance was increased in late August and September by migrating individuals [2]. In southeastern Missouri, soras were observed from 5 September to 27 October [54]. Soras have been observed in Manitoba and Saskatchewan as late as October [46].
Nesting: Although sora nesting activities have been observed from late April through early August, the peak nesting period typically occurs from May to early July. In New York, nesting was initiated in late April [34]. A nest search and literature review study of soras in Colorado reports a clutch initiated in early August. However, mean clutch initiation dates occurred in May and June in regions across the state [12]. Studies from northern Ohio [2], North Dakota [59], and Alberta [36] report nesting from May to July. In a review, sora nests with eggs were recorded from early May to early July in Indiana [42].
Sora females begin construction of saucer-shaped nests on the ground or on a platform over shallow water at the start of egg laying [12,34]. According to literature reviews, clutch sizes typically range from 8 to 13 eggs [12,42], although clutch sizes of up to 16 have been reported [12,28,36]. Both parents incubate the eggs. Incubation lasts approximately 19 days, although a wide range of incubation periods has been reported in the literature [36]. Eggs hatch over a span of 2 to 13 days [28]. Nestlings are precocial and are capable of walking and swimming short distances (<3 feet (1 m)) by the end of their 1st day. Young soras are independent by about 4 weeks of age [12,26]. According to a literature review, soras brood once per season [12]. Some late broods may be 2nd nesting attempts, but there is only 1 report in the literature of a 2nd brood attempt after a successful nest [36]. For information on breeding behavior of soras, see [28]. For information on conspecific nest parasitism and egg discrimination in soras see [58].
Sora nest success rates vary across locations and years. In summaries of the literature addressing sora apparent nest success, reported proportions of successful nests varied from 0.61 in Michigan to 0.833 in Minnesota [2,9]. In western New York, the nest success rate of 6 sora nests was 0.43, and the daily nest success rate was 0.97 [34]. Using data from the Cornell Laboratory of Ornithology's nest record program, nesting success rate of soras in North America was estimated as 0.529 over a 28-day period (n=108) [9]. On a site in Alberta, 80.6% of eggs successfully hatched, while the following year only 59.6% of eggs hatched. The authors conclude that diminished water level interacting with predators and trampling by cattle resulted in decreased hatching success [36].
During late summer, soras are flightless for a period during their post-nuptial molt [2].
Home Range: Sora home range size varies. Sora brood-rearing home ranges in northwestern Iowa averaged 0.5 acre (0.19 ha) [26]. In Arizona, sora home range size varied from 1.5 acres (0.59 ha) in the early breeding season to over 2 acres (0.91) ha in the postbreeding season. These seasonal differences in sora home range size were not significant (p>0.05) [8].
Survival: Few data are available on the survival of soras. Radio-marked soras in Arizona had a nonbreeding survival probability of 0.308. The authors suggest the low survival rate may be due to increased mortality of radio-marked birds [9]. Likely causes of mortality are predation (see Predators) and human-caused sources such as road kill [2].
Distribucion General: Se reproduce desde Alaska y el norte de Canadá hasta el noreste y suroeste de E.U.A. Invierna desde el sur de E.U.A. hasta Perú y Guyana, y también en las Antillas.
Porzana carolina[2][3] ye una especie d'ave gruiforme de la familia Rallidae, qu'habita nos banzaos de gran parte d'América.
Los adultos miden de 20 a 25 centímetros de llargu, y pesen ente 49 y 112 gramos. Tienen les partes cimeres con mancha color café, cola cara y les partes inferiores de color azul buxu, y lladrales blancos y negros.[4]
Ye una especie migradora que cría na metá norte de Norteamérica, y pasa l'iviernu nel sur d'EEXX, Méxicu, Centroamérica, el Caribe y l'estremu noroccidental de Suramérica.[5]
.
Esta páxina forma parte del wikiproyeutu Aves, un esfuerciu collaborativu col fin d'ameyorar y organizar tolos conteníos rellacionaos con esti tema. Visita la páxina d'alderique del proyeutu pa collaborar y facer entrugues o suxerencies. Porzana carolina ye una especie d'ave gruiforme de la familia Rallidae, qu'habita nos banzaos de gran parte d'América.
Ar rakig Karolina a zo un evn hag a vev el lec'hioù gleb. Porzana carolina eo e anv skiantel.
La polla pintada americana o polla pintada de Carolina[1] (Porzana carolina) és un ocell de la família dels ràl·lids (Rallidae) que habita pantans d'Amèrica del Nord, criant des del sud d'Alaska, Colúmbia Britànica i Yukon, cap al sud, a través de Canadà i Estats Units, fins Baixa Califòrnia, Nevada, Arizona, Nou Mèxic i Missouri. Passa l'hivern a Florida, les Antilles, Mèxic i Amèrica Central, fins a Colòmbia, Veneçuela i Equador.
La polla pintada americana o polla pintada de Carolina (Porzana carolina) és un ocell de la família dels ràl·lids (Rallidae) que habita pantans d'Amèrica del Nord, criant des del sud d'Alaska, Colúmbia Britànica i Yukon, cap al sud, a través de Canadà i Estats Units, fins Baixa Califòrnia, Nevada, Arizona, Nou Mèxic i Missouri. Passa l'hivern a Florida, les Antilles, Mèxic i Amèrica Central, fins a Colòmbia, Veneçuela i Equador.
Aderyn a rhywogaeth o adar yw Rhegen sora (sy'n enw benywaidd; enw lluosog: rhegennod sora) a adnabyddir hefyd gyda'i enw gwyddonol Porzana carolina; yr enw Saesneg arno yw Sora crake. Mae'n perthyn i deulu'r Rhegennod (Lladin: Rallidae) sydd yn urdd y Gruiformes.[1]
Talfyrir yr enw Lladin yn aml yn P. carolina, sef enw'r rhywogaeth.[2]
Mae'r rhegen sora yn perthyn i deulu'r Rhegennod (Lladin: Rallidae). Dyma rai o aelodau eraill y teulu:
Rhestr Wicidata:
rhywogaeth enw tacson delwedd Corsiar Porphyrio porphyrio Iâr ddŵr Allen Porphyrio alleni
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Aderyn a rhywogaeth o adar yw Rhegen sora (sy'n enw benywaidd; enw lluosog: rhegennod sora) a adnabyddir hefyd gyda'i enw gwyddonol Porzana carolina; yr enw Saesneg arno yw Sora crake. Mae'n perthyn i deulu'r Rhegennod (Lladin: Rallidae) sydd yn urdd y Gruiformes.
Talfyrir yr enw Lladin yn aml yn P. carolina, sef enw'r rhywogaeth.
Das Carolinasumpfhuhn (Porzana carolina) ist eine Vogelart aus der Familie der Rallen innerhalb der Ordnung der Kranichvögel. Es ist in Nord- und Südamerika verbreitet, kommt aber selten auch nach Europa. Ein Protonym des wissenschaftlichen Namens ist Rallus carolinus.
Das Carolinasumpfhuhn hat den für die Gattung Porzana typischen, rundlichen und plumpen Körperbau. Es erreicht eine Körperlänge von 18 bis 21 Zentimetern. Die Flügel sind kurz und breit. Der Schwanz ist kurz, keilförmig und gleichmäßig spitz zulaufend. Die kräftigen, graugelb bis grüngelb gefärbten Beine tragen drei lange, nach vorne weisende Zehen und eine im Vergleich zu den anderen kurze dünne, nach hinten weisende Zehe. Die Färbung des an der Basis gelb bis gelborange gefärbten und kräftigen, spitz zulaufenden Schnabels geht nach vorne hin in ein grünliches Gelbbraun über. Der Schnabel ähnelt dem des Tüpfelsumpfhuhns, ist jedoch etwas länger, reicht nach oben weiter auf die Stirn und läuft vorne spitzer aus. Die Nasenöffnungen sind schlitzförmig und liegen in der Mitte des Oberschnabels. Die Iris der großen Augen ist braun, um das Auge herum verläuft ein sehr schmaler, weißer und unbefiederter Lidring.
Der Altvogel sieht aus wie eine Mischung aus Kleinem Sumpfhuhn und Tüpfelsumpfhuhn. Gesicht, Vorderhals und Brust sind graublau. Vom Schnabelansatz bis zum Auge zieht sich eine schwarze, leicht gräulich schimmernde Maske, die sich – blasser werdend und als schmales Band – an der Kehle noch bis zur Brust erstreckt. Die obersten Ohrdecken sind braun. Auch die Körperoberseite von der Stirn über den Hinterkopf, Hals, Rücken, Flügel und Schwanzoberseite sind mehr oder weniger graubraun, wobei die Braunfärbung an Kopf und Hals am intensivsten ist. Mittig über den Kopf verläuft ein schwarzes Band von der Stirn bis in den Nacken. Die Rücken-, Schirm- und Armfedern tragen in ihrer Mitte einen schwarzen Fleck sowie teilweise weißliche Ränder, was das Gefieder dort geschuppt aussehen lässt. Die Handdecken sind nur weiß und schwarz gefleckt, während die kurzen Handschwingen dunkelbraun und hell quergestreift sind. Von der Brust an nach hinten wird das Gefieder zunehmend weiß gefleckt, kurz dahinter geht es in eine grobe, blasse Querbänderung über. Auf hellgrauer Grundfarbe verlaufen hier je zwei dünne schwarze Querstriche nebeneinander, zwischen denen das Gefieder braun ist. Die Unterschwanzdecken sind weiß mit klar begrenztem gelblichen Feld in der Mitte. Jungvögel sind weitgehend hellbraun gefärbt. Der Kopf-Mittelstrich ist vorhanden, das Gesicht ist jedoch hell weißlich braun mit dunklen oberen Ohrdecken. Der obere Hals sowie der obere Kopf, der Rücken, die Flügel und der Schwanz sind wie beim Altvogel gefärbt und gemustert, jedoch etwas blasser. Vorderhals und Brust sind dagegen gelbbraun bis hellbraun. Die Bauchbänderung ist noch heller. Ansonsten gleicht das Gefieder dem des Altvogels.
Das Carolinasumpfhuhn kann sowohl als Altvogel als auch als Jungvogel mit dem eurasischen Tüpfelsumpfhuhn verwechselt werden. Gute Unterscheidungsmerkmale sind jedoch beim Altvogel des Tüpfelsumpfhuhns der gesprenkelte Kopf und Hals, der rötliche Schnabel, die fehlende Gesichtsmaske (die bei schlechten Lichtverhältnissen beim Carolinasumpfhuhn jedoch ebenfalls nicht zu sehen ist), die schmälere Bänderung des Bauches und das viel größere, unscharfe gelbliche Feld auf den Unterschwanzdecken. Jungvögel dieser Art haben einen gesprenkelten Vorderkörper, einen orangen Schnabel und sechs statt eines auf dem Kopf längs verlaufende Streifen. Ähnlich sehen auch das Kleine Sumpfhuhn und das Zwergsumpfhuhn aus. Sie sind aber viel schlanker und kleiner gebaut und haben einen sehr dünnen, gelbgrünen (beim Kleinen Sumpfhuhn zusätzlich an der Basis roten) Schnabel. Als Altvogel fehlen ihnen die Gesichtsmaske, die blaugraue Färbung des Vorderkörpers reicht viel weiter herunter (bis zu den Beinen/bis zum Steiß), die Musterung der Oberseite ist viel gröber und sehr lückenhaft und die Unterschwanzdecken sind (bei beiden Geschlechtern) schwarzweiß gebändert.
Der Gesang des Carolinasumpfhuhns ist recht unterschiedlich. Es gibt langsamer und tiefer werdende Triller, die an Rufe von Zwergtauchern erinnern, ebenfalls bekannt ist ein tiefes schleppendes Pfeifen mit ansteigendem Schlusslaut, etwa wie ku-wü, was dem Ruf einer Pfuhlschnepfe beim Balzbeginn ähnelt. Tagsüber hält sich der Vogel in der Ufervegetation versteckt und kommt erst in der Dämmerung hervor. Er watet oft in flachem Wasser am Ufer umher, benutzt aber auch Seerosenblätter zum Laufen und kann auch schwimmen. Bei der Nahrungssuche ist der Vorderkörper nach unten geneigt. Das Carolinasumpfhuhn ernährt sich von Kleintieren wie zum Beispiel Insekten, aber auch von Sämereien. Das Nest wird in lückiger Ufervegetation errichtet. Es ist ein Schwimmnest oder befindet sich auf niedrigen Ästen und Zweigen. Es besteht aus Wasserpflanzen wie Schilf und Binsen, aber auch aus Zweigen und Blättern. Brutgebiete sind Überschwemmungsgebiete, feuchte Wiesen oder Sümpfe. Die Art ist ein Zugvogel.
Das Carolinasumpfhuhn ist in Nordamerika und Südamerika beheimatet, wo es Feuchtwiesen, Sümpfe, Überschwemmungsgebiete und andere Gewässer bewohnt. Das Brutgebiet reicht von der Hudson Bay nach Vancouver Island und im Osten bis zur Labrador-Halbinsel, von dort über Südkanada und die USA bis nach Mexiko und auf einige karibische Inseln. Überwinterungsgebiete befinden sich von den südlichen USA über das gesamte Mittelamerika bis nach Venezuela, Guayana und Französisch-Guayana, dann in zwei Streifen westlich sowie östlich des Hauptkamms der Anden bis nach Ecuador und Peru, der westliche Streifen reicht bis zum Pazifik. Auch die karibischen Inseln werden zum Überwintern aufgesucht. Das Carolinasumpfhuhn ist eine Ausnahmeerscheinung in Russland, Alaska, auf Galapagos, Hawaii, den atlantischen Inseln und Marokko. Selten erscheint die Art außerdem in Europa, dort aber hauptsächlich nur im Westen, in Portugal, Spanien, Frankreich, Irland, Großbritannien und Schweden.
Die Art wird von der IUCN als least concern (nicht gefährdet) eingestuft.
Das Carolinasumpfhuhn (Porzana carolina) ist eine Vogelart aus der Familie der Rallen innerhalb der Ordnung der Kranichvögel. Es ist in Nord- und Südamerika verbreitet, kommt aber selten auch nach Europa. Ein Protonym des wissenschaftlichen Namens ist Rallus carolinus.
The sora (Porzana carolina) is a small waterbird of the rail family Rallidae, sometimes also referred to as the sora rail or sora crake, that occurs throughout much of North America. The genus name Porzana is derived from Venetian terms for small rails, and the specific carolina refers to the Carolina Colony. The common name "Sora" is probably taken from a Native American language.
Adult soras are 19–30 cm (7.5–11.8 in) long, with dark-marked brown upperparts, a blue-grey face and underparts, and black and white barring on the flanks. They have a short thick yellow bill, with black markings on the face at the base of the bill and on the throat. Sexes are similar, but young soras lack the black facial markings and have a whitish face and buff breast. They weigh about 49–112 g (1.7–4.0 oz).
The sora's breeding habitat is marshes throughout much of North America. They nest in a well-concealed location in dense vegetation. The female usually lays 10 to 12 eggs, sometimes as many as 18, in a cup built from marsh vegetation. The eggs do not all hatch together. Both parents incubate and feed the young, who leave the nest soon after they hatch and are able to fly within a month.
They migrate to the southern United States and northern South America. Sora is a very rare vagrant to western Europe, where it can be confused with spotted crake. However, the latter species always has spotting on the breast. a streaked crown stripe, and a different wing pattern.
Soras forage while walking or swimming. They are omnivores, eating seeds, insects and snails. Although soras are more often heard than seen, they are sometimes seen walking near open water. They are fairly common, despite a decrease in suitable habitat in recent times. The call is a slow whistled ker-whee, or a descending whinny. The use of call broadcasts greatly increases the chances of hearing a sora. Call broadcasts can also increase the chances of seeing a sora, as they will often investigate the source of the call.
The sora was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae. He placed it with the rails in the genus Rallus and coined the binomial name Rallus carolinus.[2] Linnaeus based his description on the "little American water hen" that George Edwards had described and illustrated in 1750 from a specimen collected near the Hudson Bay.[3] Linnaeus also cited Mark Catesby who had described the "soree" in his The Natural History of Carolina, Florida and the Bahama Islands.[4] The sora is now placed in the genus Porzana that was erected in 1816 by the French ornithologist Louis-Pierre Vieillot.[5][6] The genus name is derived from Venetian terms for small rails, the specific epithet refers to the Carolina Colony.[7] The common name "Sora" is probably taken from a Native American language.[8] The species in monotypic: no subspecies are recognised.[6]
Adult soras are 19–30 cm (7.5–11.8 in)[9][10][11] long, with dark-marked brown upperparts, a blue-grey face and underparts, and black and white barring on the flanks. They have a short thick yellow bill, with black markings on the face at the base of the bill and on the throat. Sexes are similar, but young soras lack the black facial markings and have a whitish face and buff breast. They weigh about 49–112 g (1.7–4.0 oz)[9] and have a wingspan of 35–40 cm.[12] Soras have two common calls: a loud, squeaking "whinny" that decelerates and descends in pitch, often used to advertise territories; and a softer, ascending "ker-wee" or "sor-ah".[13] The latter call is sometimes presented as a possible origin for the species' common name.
The sora is common across North America, naturally occurring in 49 US states (the exception being Hawaii), all 10 Canadian provinces and 2 Canadian territories. Outside of US/Canada, the species is found throughout Central America, the Caribbean, and northern South America. The species has been recorded as a vagrant in Iceland, Great Britain, Portugal, and at Lake Titicaca.
Soras occur throughout most of North America.[14] Soras breed from Nova Scotia northwest to southern Yukon and Northwest Territories, south to California, Arizona, and New Mexico and northeast to Pennsylvania and New England. Sora wintering grounds include the Caribbean, northern portions of South America, including Ecuador, Colombia, and Venezuela, north through Central America and Mexico to southern California in the West and coastal regions of the Southeast. From southern Kansas south to northern and eastern Texas and east through the inland areas of the southeastern United States, soras are typically only observed during migration in the spring and fall. In a few areas of the western United States, including central California and areas of Arizona and New Mexico, soras may occur year-round.[14]
The size of an individual Sora's home range varies. Sora brood-rearing home ranges in northwestern Iowa averaged 0.5 acres (0.20 ha).[15] In Arizona, sora home range size varied from 1.5 acres (0.61 ha) in the early breeding season to over 2 acres (0.81 ha) in the postbreeding season. These seasonal differences in sora home range size were not significant (p>0.05).[16]
Densities vary from to 12 soras/acre in Colorado [17] to 0.47 pair/ha in Indiana.[18] An average of 1.3 soras/ha responded to calls across sites in Colorado.[19] A similar density of soras was found in southeastern Wisconsin.[20] In Iowa, average density over 2 years and several marsh habitats was 1.3 pairs/ha.[21] ≥Landscape factors, such as marsh area, habitat edges within marshes, and the number of marshes in a region may influence soras.
Although soras occur in marshes of all sizes, they may occur at higher densities in intermediate-sized marshes. Soras were significantly (p≤0.01) positively related with total wetland area and perimeter area of surface water in east and central Maine [22] and were significantly (p<0.05) positively related to area of wetlands in Saskatchewan.[23] In Maine, soras used 10% of 2.5 acres (1.0 ha) wetlands, 40% to 50% of wetlands from 2.5–5 acres (1.0–2.0 ha) in size, and 20% of wetlands larger than 50 acres (20 ha).[22] In western New York, soras were significantly (p=0.007) more abundant in marshes from 100 to 250 acres (40 to 101 ha) in size than in smaller (< 100 acres (40 ha)) or larger (250–380 acres (100–150 ha)) marshes. In addition, sora nests were detected more often in the 100–200 acres (40–81 ha) marshes.[24]
Soras are commonly reported in plant communities dominated by cattails (Typha spp.),[16][19][25][24][26][20] sedges (Carex spp.),[19][26][20][21][27] bulrushes (Scirpus spp.),[16][19][20][21] smartweeds (Polygonum spp.),[26][27] rushes (Juncus spp.),[26][27] rice cutgrass (Leersia oryzoides),[28] and barnyard grasses (Echinochloa spp.).[27][28]
Soras also seem to prefer edge habitats. Breeding sora density was significantly (p<0.001) correlated (r=0.62) with the perimeter:area ratio of northwestern Iowa marshes. The distance from the center of sora territories to a habitat edge was also significantly (p<0.005) less than from the center of Virginia rail territories.[21] In Arizona, habitat edges were closer to sora heavy use areas than random sites.[16]
Wetland dynamics at a large scale can affect soras. Indices of sora population at 3 "levels of response" were significantly (p<0.01) correlated (r≥0.70) with the number of ponds present in the prairie pothole region of North Dakota in May.[29]
Outside of wetlands, soras are most often reported in cultivated areas during migration or in the postbreeding period. For instance, a sora was observed 3 mi (4.8 km) from marshland in a cultivated field in Iowa in the middle of August. A male sora was observed less than 1,000 ft (300 m) from a large wetland in a soybean (Glycine max) field in northwestern Iowa during the postbreeding period.[15] From early June to mid-July, soras were observed on farms in Saskatchewan sown mainly with wheat (Triticum aestivum).[23]
Soras have also been reported in flooded wooded areas.[24][22] In western New York, soras occurred during the breeding season on a study site where 26% of the area was categorized as "flooded timber," and 5% was classed as "scrub/shrub marsh".[24] In eastern and central Maine, an average of 2.1 soras was observed in wooded swamps per 100 hours of observation during the breeding season.[22] On a nonbreeding (August–April) site in southwestern Arizona, soras were found to use a "mixed shrub community" more than expected based on its availability.[16] Soras were observed at low abundances on a site with douglas-fir (Pseudotsuga menziesii), ponderosa pine (Pinus ponderosa), and trembling aspen (Populus tremuloides) in British Columbia.[30]
Soras use areas with a wide range of water depths. They are often observed in water less than 1 ft (30 cm) deep,[19][20][27][28] although the average water depth of sora heavy-use areas in Arizona was 20 in (51 cm) .[16] In northwestern Iowa, average water depth in sora territories was 15 in (38 cm), which was significantly (p<0.025) more shallow than water depths at random locations in the marsh.[21] Sora nesting sites occurred in shallower water than random sites in western New York.[24] Average water depths reported at nest sites range from 4 in (10 cm) for 4 sora nests in Colorado to nearly 10 in (25 cm) for sora nests in western New York.[24] In areas of deep water, soras typically wade on mats of floating vegetation.[15]
Water level fluctuations may result in nest abandonment. For example, at a site in Colorado where water level increased more than 8 in (20 cm), a sora nest with 7 eggs was abandoned.[19] In Alberta, soras nested in more vegetation types during a drought year, most likely due to substantially reduced water levels in the vegetation used the previous year.[26]
Soras use areas with shallower water in fall than in spring.[16][27][28] Soras typically avoid open water. There is a significant (p≤0.05) negative relationship between area of open water and sora use of wetlands in Maine [22] and sora relative abundance in Saskatchewan.[23] In western New York, sora nesting sites had a lower percentage of open water than random sites,[24] and in Arizona soras used open water areas less than their availability.[16]
Sora nesting sites had larger percentage of emergent vegetation than random sites in marshes of western New York.[24] Sora numbers in wetlands of northeastern North Dakota were significantly (p<0.05) positively correlated (r=0.45) with hectares of live emergent vegetation. In east and central Maine, wetlands used by soras had significantly (p=0.01) greater area of emergent vegetation than unused wetlands.[22]
Density of emergent vegetation in sora habitat varies. Reported density of emergent vegetation ranges from an average of 121.9 stems/m2 in sora territories in northwestern Iowa [21] to 333 stems/m2 on sites in northeastern Missouri used during fall migration.[28] In western New York, cover was greater than 70% at 95% of sora nests. In addition, nesting sites had more horizontal cover at 20 inches (0.5 m) above water level than random sites.[24] However, average stem density on sora territories was not significantly (p>0.05) different from random sites in northwestern Iowa.[21]
Height of emergent vegetation in sora habitat also varies. It ranged from 8 to 11 in (20 to 28 cm) in the spring after a winter disturbance in northwestern Iowa [21] to 84 in (210 cm) in areas heavily used by soras in Arizona.[16] In marshes of western New York, average vegetation height at sora nesting sites was shorter than at random locations.[24] However, the average height of emergent vegetation in sora territories in northeastern Iowa was not significantly (p>0.05) different from the height of vegetation in random plots.[21]
In Arizona, both cover and height of vegetation used by soras varied with seasons. Conway suggested the differences likely reflected the varied diet of the sora.[16] The availability of habitat in different seasons is another possible source of seasonal differences in sora habitat.[27]
Extent of woody vegetation surrounding South Dakota wetlands was not significantly (p=0.6) associated with sora occurrence. However, in marshes of western New York, there was a significant (p=0.041) negative relationship between percent flooded timber on a site and sora relative abundance.[24]
Soras may prefer some cover types. In Arizona, 65.3% of sora use was in southern cattail (Typha domingensis), although it comprised only 16.5% of the vegetation. Bulrushes and a mixed-shrub community were also used more than their availability, while saltcedar (Tamarix chinensis) and arrowweed (Pluchea sericea) were avoided.[16] A literature review notes sora avoidance of purple loosestrife (Lythrum salicaria)-dominated sites. In east and central Maine, wetlands used by soras had significantly (p=0.05) more ericaceous vegetation, such as leatherleaves (Chamaedaphne spp.), sweetgales (Myrica spp.), and laurels (Kalmia spp.).[22] In marshes of northwestern Iowa, broadleaf arrowhead (Sagittaria latifolia) occurred in sora territories significantly (p<0.01) more often than at random sites. Johnson and Dinsmore [21] imply that this likely results from both species preferring similar site conditions. In May and June in Wisconsin, soras were detected significantly (p<0.025) more often in cattail (Typha spp.) survey areas than in sedge areas. However, in southeastern Wisconsin during the breeding season, there was no significant (p=0.943) difference in sora densities between habitats comprised predominantly of cattail, sedge, or bulrush.[20] In addition, soras' use of glaucous cattail (Typha × glauca), broadfruit bur-reed (Sparganium eurycarpum), sedge, river bulrush (Schoenoplectus fluviatilis), and hardstem bulrush (S. acutus var. acutus) habitats in marshes of northwestern Iowa generally reflected availability of these habitats.[21]
Seasonal differences in sora habitat use have been reported. In northeastern Missouri in spring, the likelihood of detecting sora in robust emergents, such as cattail (Typha spp.) and longroot smartweed (Polygonum amphibium var. emersum), was over 6 times that of detecting soras in these areas in fall. However, availability of habitats during various times of the year was not addressed.[28] In a study performed in southeastern Missouri, plant species used by sora during spring and fall migration differed significantly (p=0.005). However, the author qualifies this finding with his observation of major seasonal differences in vegetation availability.[27]
Temperature may also influence sora abundance. In Colorado, average April temperature was significantly (p<0.01) negatively correlated (r= -0.94) with sora abundance. On sites that had average April temperatures ≤ 42 °F (6 °C), soras were more abundant than the closely related Virginia rail (Rallus limicola), while on warmer sites the sora to Virginia rail ratio declined.[19]
They migrate to the southern United States, the Caribbean, and northern South America. Sora is a very rare vagrant to western Europe, where it can be confused with spotted crake. However, the latter species always has spotting on the breast. a streaked crown stripe, and a different wing pattern.
Soras forage while walking or swimming. They are omnivores, eating seeds, insects and snails. Although soras are more often heard than seen, they are sometimes seen walking near open water. They are fairly common, despite a decrease in suitable habitat in recent times. The call is a slow whistled ker-whee, or a descending whinny. The use of call broadcasts greatly increases the chances of hearing a sora. Call broadcasts can also increase the chances of seeing a sora, as they will often investigate the source of the call.
Sora's northern migration occurs in spring, primarily in April and May. For instance, in east-central Kansas significantly (p<0.05) more soras were detected from 24 April to 7 May than the 2-week periods before or after. In southeast Missouri, soras were observed from 25 March to 6 May.[27] Soras were first detected in April to early May in Colorado,[19] Iowa, and Minnesota.[25] In a summary of the first detections of soras in Minnesota, Manitoba, and Saskatchewan, all occurred in April.[31]
Soras depart their breeding grounds as early as July and as late as October. Soras were observed returning to wintering grounds in Arizona as early as late July.[16] Although local movements may obscure migration occurring in July, most migration occurred in August and September in Colorado. In northern Ohio, sora abundance was increased in late August and September by migrating individuals.[32] In southeastern Missouri, soras were observed from 5 September to 27 October.[27] Soras have been observed in Manitoba and Saskatchewan as late as October.[31]
Although sora nesting activities have been observed from late April through early August, the peak nesting period typically occurs from May to early July. In New York, nesting was initiated in late April.[24] A nest search and literature review study of soras in Colorado reports a clutch initiated in early August. However, mean clutch initiation dates occurred in May and June in regions across the state.[17] Studies from northern Ohio,[32] North Dakota, and Alberta [26] report nesting from May to July. In a review, sora nests with eggs were recorded from early May to early July in Indiana.[18]
The sora's breeding habitat is marshes throughout much of North America.[33] They nest in a well-concealed location in dense vegetation. The female usually lays 10 to 12 eggs, sometimes as many as 18, in a cup built from marsh vegetation. The eggs do not all hatch together. Both parents incubate and feed the young, who leave the nest soon after they hatch and are able to fly within a month.
Sora females begin construction of saucer-shaped nests on the ground or on a platform over shallow water at the start of egg laying.[24][17] Clutch sizes typically range from 8 to 13 eggs,[17][18] although clutch sizes of up to 16 have been reported.[25][26][17] Both parents incubate the eggs. Incubation lasts approximately 19 days, although a wide range of incubation periods has been reported in the literature.[26] Eggs hatch over a span of 2 to 13 days.[25] Nestlings are precocial and are capable of walking and swimming short distances (< 3 ft (0.91 m)) by the end of their first day. Young soras are independent by about 4 weeks of age.[15][17] Soras brood once per season.[17] Some late broods may be second nesting attempts, but there is only one report in the literature of a second brood attempt after a successful nest.[26] For information on breeding behavior of soras, see.[25] For information on conspecific nest parasitism and egg discrimination in soras see.[34]
Sora nest success rates vary across locations and years. In the literature addressing sora apparent nest success, the proportions of successful nests varied from 0.61 in Michigan to 0.833 in Minnesota.[32] In western New York, the nest success rate of 6 sora nests was 0.43, and the daily nest success rate was 0.97.[24] Using data from the Cornell Laboratory of Ornithology's nest record program, nesting success rate of soras in North America was estimated as 0.529 over a 28-day period (n=108).[35] On a site in Alberta, 80.6% of eggs successfully hatched, while the following year only 59.6% of eggs hatched. The authors conclude that diminished water level interacting with predators and trampling by cattle resulted in decreased hatching success.[26] During late summer, soras are flightless for a period during their post-nuptial molt.[32]
Soras eat a wide range of foods. Animals that are commonly reported as sora food items include snails (Gastropoda), crustaceans (Crustacea), spiders (Araneae), and insects (Insecta), mainly beetles (Coleoptera), grasshoppers (Orthoptera), flies (Diptera), and dragonflies (Odonata).[36][37] Soras often eat the seeds of plants, such as smartweeds, bulrushes, sedges, and barnyard grasses.[32][36][37] Seeds of annual wildrice (Zizania aquatica) and rice cutgrass are eaten by soras in the eastern United States.[36] A literature review lists crowngrass (Paspalum spp.) and rice (Oryza sativa) as relatively important food sources for soras in the Southeast. Plants comprising <5% of the sora's diet are also listed and include spikerushes (Eleocharis spp.), duckweeds (Lemnaceae), pondweeds (Potamogeton spp.), panicgrasses (Panicum spp.), cordgrasses (Spartina spp.), and saltgrass (Distichlis spicata).[36]
Soras eat more plant food in fall and winter (68%–69%) than in spring and summer (40%).[36] Plant material such as hairy crabgrass (Digitaria sanguinalis), fall panicgrass (Panicum dichotomiflorum), and bristlegrass (Setaria spp.) occurred at substantially higher frequencies and in much larger volumes in sora esophagi collected in southeastern Missouri during fall migration than those collected in spring. In addition, animals comprised a larger volume of the spring diet than the fall diet. The volume of animal material in esophagi collected in spring was predominantly composed of adult beetles and snails from the Physidae family.[37]
Few data are available on the survival of soras. Radio-marked soras in Arizona had a nonbreeding survival probability of 0.308. The authors suggest the low survival rate may be due to increased mortality of radio-marked birds.[35] Likely causes of mortality are predation and human-caused sources such as road kill.[32]
Sora eggs are eaten by several species including American minks (Neogale vison), skunks (Mephitidae), coyotes (Canis latrans), grackles (Quiscalus spp.), crows (Corvus spp.), and herons (Ardeidae).[26][32] Predation of adult soras by American minks, coyotes, and hawks and owls have been reported.[26][31]
This article incorporates public domain material from Porzana carolina. United States Department of Agriculture.
The sora (Porzana carolina) is a small waterbird of the rail family Rallidae, sometimes also referred to as the sora rail or sora crake, that occurs throughout much of North America. The genus name Porzana is derived from Venetian terms for small rails, and the specific carolina refers to the Carolina Colony. The common name "Sora" is probably taken from a Native American language.
Adult soras are 19–30 cm (7.5–11.8 in) long, with dark-marked brown upperparts, a blue-grey face and underparts, and black and white barring on the flanks. They have a short thick yellow bill, with black markings on the face at the base of the bill and on the throat. Sexes are similar, but young soras lack the black facial markings and have a whitish face and buff breast. They weigh about 49–112 g (1.7–4.0 oz).
The sora's breeding habitat is marshes throughout much of North America. They nest in a well-concealed location in dense vegetation. The female usually lays 10 to 12 eggs, sometimes as many as 18, in a cup built from marsh vegetation. The eggs do not all hatch together. Both parents incubate and feed the young, who leave the nest soon after they hatch and are able to fly within a month.
They migrate to the southern United States and northern South America. Sora is a very rare vagrant to western Europe, where it can be confused with spotted crake. However, the latter species always has spotting on the breast. a streaked crown stripe, and a different wing pattern.
Soras forage while walking or swimming. They are omnivores, eating seeds, insects and snails. Although soras are more often heard than seen, they are sometimes seen walking near open water. They are fairly common, despite a decrease in suitable habitat in recent times. The call is a slow whistled ker-whee, or a descending whinny. The use of call broadcasts greatly increases the chances of hearing a sora. Call broadcasts can also increase the chances of seeing a sora, as they will often investigate the source of the call.
La Sorao, Soraralo aŭ Karolinia porzano, (Porzana carolina), estas eta akvobirdo, de la familio de Raledoj kaj ordo de Gruoformaj. Breda medio de Karolinia porzano estas marĉoj de preskaŭ tuta norda Ameriko, tio estas suda Kanado, norda kaj okcidenta Usono kaj ĝi vintras en centra Ameriko kaj norda Sudameriko, pli precize en orienta kaj suda marbordoj de Usono, Centrameriko kaj Karibo, kaj marbordo de Kolombio, Venezuelo kaj Ekvadoro.
Plenkreskuloj de Karolinia porzano estas 18-21 cm longaj, kun malhele vertikale markitaj brunaj supraj partoj, grizbluaj vizaĝo kaj subaj partoj kaj nigroblankaj horizontalaj strioj ĉeflanke. Ili havas mallongan dikan flavan bekon kun nigra marko en la vizaĝo inter la beko kaj okulo kaj ĉe gorĝe. Kruroj estas flavverdaj. La vosto restas kutime rekta ĉielen montrante blankan suban parton. Ambaŭ seksoj estas similaj, sed junuloj malhavas la blankan vizaĝan markon kaj havas blankecan vizaĝon kaj okran bruston.
La Karolinia porzano estas bone adaptita al vivo en ties densa medio. Ĝi estas flankebena kaj ĝiaj mallongaj rondformaj flugiloj permesas manovri inter junkaro.
Karolinia porzano estas tre rara vaganto al okcidenta Eŭropo, kie ĝi povas esti konfuzata kun Makula porzano. Tamen tiu lasta specio ĉiam havas punktadon en brusto, striadon en kapa strio kaj malsimila flugila bildo.
Antaŭ reproduktado okazas paraj ceremonioj kaj dum bredado la paro defendas ties teritorion kaj agreseme ĉasa invaduntojn. Ili konstruas neston en bone kaŝita loko inter densa vegetalaro. La ino demetas plej ofte 10 ĝis 12 brunajn ovojn, foje ĝis 18, en ujo konstruita el marŝa plantaro, foje per du demetadoj por enmeti tiom da ovoj en tiom malgranda ujo. La ovoj ne malfermiĝas samtempe. Ambaŭ gepatroj kovas malpli ol tri semajnoj kaj zorgas la idojn, kiuj elnestiĝas tuj post eloviĝo kaj kapablas flugi post unu monato.
Karolinia porzano manĝas dum piedirado aŭ naĝado. Ili estas ĉiomanĝantaj, tio estas semoj, insektoj kaj helikoj.
Post bredado ili sociiĝas en nombraj aroj ĝis migrado, kio okazas nokte.
Kvankam Sorao estas pli aŭdata ol vidata, ĝi vidiĝas foje piedirante ĉe akvobordo. Ili estas sufiĉe komunaj spite la kostanta malpliigo de ties medio. Tamen ĝi estas sekretema specio, kiel aliaj raledoj.
La voĉo estas fajfa ku-vu.
La Sorao, Soraralo aŭ Karolinia porzano, (Porzana carolina), estas eta akvobirdo, de la familio de Raledoj kaj ordo de Gruoformaj. Breda medio de Karolinia porzano estas marĉoj de preskaŭ tuta norda Ameriko, tio estas suda Kanado, norda kaj okcidenta Usono kaj ĝi vintras en centra Ameriko kaj norda Sudameriko, pli precize en orienta kaj suda marbordoj de Usono, Centrameriko kaj Karibo, kaj marbordo de Kolombio, Venezuelo kaj Ekvadoro.
La polluela sora o polluela norteña (Porzana carolina)[2][3] es una especie de ave gruiforme de la familia Rallidae, que habita en los pantanos de gran parte de América.
Los adultos miden de 20 a 25 centímetros de largo, y pesan entre 49 y 112 gramos. Tienen las partes superiores con manchas color café, con el rostro y las partes inferiores de color azul grisáceo, y flancos blancos y negros.[4]
Es una especie migradora que cría en la mitad norte de Norteamérica, y pasa el invierno en el sur de EE. UU., México, Centroamérica, el Caribe y el extremo noroccidental de Sudamérica.[5]
_bird_waterbird_in_Morro_Bay_(by).jpg)
|coautores= (ayuda) La polluela sora o polluela norteña (Porzana carolina) es una especie de ave gruiforme de la familia Rallidae, que habita en los pantanos de gran parte de América.
Porzana carolina Porzana generoko animalia da. Hegaztien barruko Rallidae familian sailkatua dago.
Amerikanhuitti (Porzana carolina) on rantakanojen heimoon kuuluva lintulaji, joka on sukua Suomessa pesivälle luhtahuitille. Laji on kotoisin Pohjois-Amerikasta, eikä sitä ole havaittu Suomessa: Rariteettikomitea hylkäsi touko-kesäkuun vaihteessa 2007 Salon Halikonlahdelta ilmoitetun havainnon.[2]
Amerikanhuitti on pienempi kuin luhtahuitti, noin kottaraisen kokoinen. Sen pituus on 18–21 senttimetriä. Amerikanhuitilla on lyhyt, suora keltainen nokka. Sillä on siniharmaa rinta ja ruskeahko selkäpuoli. Kyljissä on valkeita raitoja. Pitkävarpaiset jalat ovat vihreät ja pyrstö lyhyt. Naaras on koirasta hiukan täplikkäämpi ja väritykseltään himmeämpi.
Amerikanhuitti on kotoisin Pohjois-Amerikasta ja Euroopassa hyvin harvinainen.
Luhtahuitin tavoin amerikanhuitti viihtyy erilaisilla kosteikoilla, tavallisimmin märillä rantaluhdilla, toisinaan myös ruoikoissa ja osmankäämiköissä. Sitä näkee harvoin, mutta sen ääni kuuluu hyvin.
Amerikanhuitti (Porzana carolina) on rantakanojen heimoon kuuluva lintulaji, joka on sukua Suomessa pesivälle luhtahuitille. Laji on kotoisin Pohjois-Amerikasta, eikä sitä ole havaittu Suomessa: Rariteettikomitea hylkäsi touko-kesäkuun vaihteessa 2007 Salon Halikonlahdelta ilmoitetun havainnon.
A galiñola da Carolina[2] ou poliña americana[3] (Porzana carolina) é unha pequena ave acuática gruiforme da familia dos rálidos. Vive en América do Norte. En Galicia pode aparecer como ave accidental.[2] O nome do xénero, Porzana, deriva do termo sporzana da lingua veneciana que designaba este tipo de aves, e carolina refírese á colonia de Carolina dos tempos da colonización inglesa de Norteamérica.[4]
Os adultos teñen unha lonxitude de entre 19 e 30 cm,[5][6][7] coas partes superiores marróns con marcas negras, e cara e partes inferiores grises azuladas, e un barrado branco e negro nos flancos. Teñen un bico curto, groso e amarelo con marcas negras na face na base do bico e na gorxa. Os sexos son similares, pero os individuos novos carecen das marcas faciais negras e teñen unha cara abrancazada e peito beixe. Pesan entre 49 e 112 g.[5]
O hábitat de reprodución da galiñola da Carolina son pantanos de gran parte de Norteamérica.[8] Nidifican en sitios ben agochados entre densa vexetación. A femia xeralmente pon de 10 a 12 ovos, ás veces chega a poñer 18, nun niño con forma de cunca construído con vexetación do pantano. Os ovos non fan eclosión todos á vez. Ambos os pais incuban e alimentan as crías, as cales abandonan o niño pouco despois da eclosión e poden voar un mes despois.
Migran ao sur dos Estados Unidos e norte de Suramérica. Son aves errantes moi raras en Europa occidental (accidentais en Galicia[2]), onde se poden confundir coa galiñola pinta. Porén, esta última ten sempre un peito con pintas, unha banda na parte superior da cabeza e un debuxo diferente nas ás.
Aliméntanse mentres camiñan ou nadan. Son omnívoras e comen sementes, insectos e caracois. Aínda que son aves máis fáciles de oír que de ver, ás veces poden verse camiñando preto de augas abertas. Son bastante comúns, malia a diminución nos últimos tempos dos hábitats axeitados para elas. A súa chamada é un asubío lento que soa ker-ui, ou un rincho descendente. Usar gravacións coa súa chamada incrementa moito as posibilidades de oíla e vela, xa que adoita investigar a fonte da chamada.
Vive na maior parte de América do Norte,[9] onde é unha especie común que aparece de forma natural en 49 dos estados de Estados Unidos (a única excepción é Hawai), as 10 provincias de Canadá e 2 teritorios canadenses. Reprodúcese desde Nova Escocia e cara ao noroeste ata o sur do Yukón e Territorios do Noroeste, cara ao sur ata California, Arizona e Novo México e cara ao nordeste ata Pennsylvania e Nova Inglaterra. Os terreos de invernda están na parte norte de Suramérica, incluíndo Ecuador, Colombia e Venezuela, cara ao norte por América Central e México ata o sur de California polo oeste e ata as rexións costeiras do sur dos Estados Unidos. Desde o sur de Kansas ata o norte e leste de Texas e nas áreas interiores do sueste de Estados Unidos, esta ave obsérvase normalmente só durante a migración da primavera e outono. Nunhas poucas áreas do oeste de Estados Unidos, como California central e áreas de Arizona e Novo México, a galiñola da Carolina pode estar presente todo o ano.[9] En Europa occidental, incluída Galicia, é unha ave accidental, e a especie foi rexistrada tamén en Islandia, Gran Bretaña e Portugal. En Suramérica rexistrouse como ave errante no Lago Titicaca andino.
A migración cara ao norte da galiñola da Carolina ocorre en primavera, principalmente en abril e maio. Por exemplo, no centro leste de Kansas detectáronse significativamente (p<0,05) máis galiñolas desde o 24 abril ao 7 de maio que os períodos de dúas semanas anteir e posterior. No sueste de Missouri, foron observadas desde o 25 de marzo ao 6 de maio.[10] En cambio, detectáronse primeiro en abril e ata inicios de maio en Colorado,[11] Iowa, e Minnesota.[12] Nun resumo sobre as primeiras deteccións de galiñolas da Carolina en Minnesota, Manitoba e Saskatchewan, a conclusión era que estas ocorreran en abril.[13]
A partida das galiñolas aos seus tereos de reprodución empeza en xullo e acaba en outubro. Foron observadas regresando aos tereos de invernada en Arizona ata xullo.[14] Aínda que os movementos locais poden escurecer a migración de xullo, a maioría da migración ocorreu en agosto e setembro en Colorado. No norte de Ohio, a abundancia da especie incrementábse a finais de agosto e setembro pola chegada de individuos migrantes.[15] No sur de Missouri, foron obsevadas desde o 5 de setembro ao 27 de outubro.[10] Foron observadas en Manitoba e Saskatchewan en outubro.[13]
Aínda que as actividades de nidificación da galiñola da Carolina se observaron desde finais de abril ata principios de agosto, o pico do período de nidificación ocorre tipicamente desde maio a inicios de xullo. En Nova York, a nidificación iniciábase a finais de abril.[16] Un estudo de niños e de datos na litratura destas galiñolas en Colorado informou dunha posta iniciada a inicios de agosto. Porén, os datos do inicio medio da posta indicaban que ocorría en maio e xuño en rexións do estado.[17] Os estudos feitos no norte de Ohio,[15] Dacota do Norte e Alberta [18] informan de nidacións desde maio a xullo. Noutro estudo recompilatorio informouse de niños con ovos de galiñola da Carolina desde inicios de maio a inicios de xuño en Indiana.[19]
As femias empezan a construción dos niños con forma de pratiño no chan ou sobre unha plataforma sobre augas pouco profundas ao inicio da posta dos ovos.[16][17] O tamaño de posta normalmente oscila de 8 a 13 ovos,[17][19] aínda que se informou de tamaños de posta de ata 16 ovos.[12][17][18] Os dous pais incuban os ovos. A incubación dura aproximadamente 19 días, aínda que se informou na literatura dun amplo rango de períodos de incubación.[18] Os ovos fan eclosión nun período de 2 a 13 días.[12] As crías son precoces e capaces de camiñar e nadar curtas distancias (< 0,91 m) ao final do seu primeiro día. As galiñolas novas son independentes aproximadamente ás 4 semanas de idade.[17][20] Crían só unha vez por estación.[17] Algunhas roladas de polos poden ser segundos intentos de nidación, pero só hai un informe na literatura dun segundo intento de nidificar despois dunha nidificación exitosa.[18] Para máis información sobre o comportamento reprodutor da galiñola da Carolina, ver.[12] Para información sobre parasitismo de crianza conespecífico e a discriminación entre ovos propios e alleos na galñola da Carolina, ver.[21]
As taxas de éxito na nidación varían segundo o lugar e o ano. Na literatura as proporcións de nidación exitosa varían desde 0,61 en Míchigan a 0,833 en Minnesota.[15] No oeste de Nova York, a taxa de éxito de 6 niños de galiñola da Carolina era do 0,43, e a do éxito diario era de 0.97.[16] Usando datos do programa de rexistro de niños do Laboratorio Cornell de Ornitoloxía, a taxa de éxito de nidación en Norteamérica estimouse en 0,529 nun período de 28 días (n=108).[22] Nun sitio de nidación en Alberta, o 80,6% dos ovos fixo eclosión con éxito, mentres que ao ano seguinte só o 59,6% dos ovos fixeron eclosión. Os autores chegaron á conclusión de que a diminución do nivel de auga interaccionando con predadores e a posibilidade de ser pisados polo gando tiña como resultado un decrecemento no éxito da eclosión.[18] Durante a parte final do verán, as galiñolas da Carolina non poden voar durante un período no que realizan a muda posnupcial.[15]
O tamaño da área onde habita (home range) un determinado individuo de galiñola da Carolina varía. A área de reproducíon e cría no noroeste de Iowa é como media de 0,20 ha.[20] En Arizona, o tamaño da área varía de 0,61ha no inicio da estación reprodutora a 0,81 ha na estación posreprodutora. Estas diferenzas estacionais no tamaño da área onde habita non son significativas (p>0,05).[14]
Disponse de poucos datos sobre a supervivencia da especie. Exemplares marcados con radio (con diminutos transmisores pegados ás costas) en Arizona tiñan unha probabilidade de supervivencia non reprodutora de 0,308. Os autores suxiren que a baixa taxa de supervivencia pode deberse a un incremento da mortalidade das aves marcadas con radio.[22] Causas probables desta mortalidade son a predación e causas de orixe humana como a morte por atropelos nas estradas.[15]
Zonas húmidas con vexetación emerxente.
A galiñola da Carolina utiliza zonas con augas de diversas profundidades. Foron observadas con frecuencia en augas de menos de 30 cm de profundidade,[10][11][23][24] aínda que a media de profundidade das zonas das que fai elevado uso esta galiñola en Arizona era de 51 cm.[14] No noroeste de Iowa, a media da profundidade da auga nos territorios destas galiñolas era de 38 cm, a cal era unha profundidade significativamente (p<0,025) menor que as profundidades en sitios ao azar en pantanos.[25] Os sitios de nidificación estaban situados en augas menos profundas que os sitios ao azar onde vive no oeste de Nova York.[16] A media de profundidade das augas en sitios de nidación era de 10 cm en 4 niños de galiñola da Carolina estudados en Colorado a case 25 cm no oeste de Nova York.[16] En áreas de augas profundas, normalmente camiñan sobre balsas de vexetación flotante.[20]
As flutuacións no nivel da auga poden causar o abandono dos niños. Por exemplo, nun sitio de Colorado onde o nivel da auga se incrementaba máis de 20 cm, un nino destas galiñolas foi abandonado con 7 ovos.[11] En Alberta, nidifican en máis tipos de vexetación durante os anos secos, moi probablemente debido a unha redución substancial do nivel da auga na vexetación usada o ano anterior.[18]
Utilizan augas menos profundas en outono que en primavera.[10][14][24] Normalmente evitan as augas abertas. Hai unha relación negativa significativa (p≤0,05) entre a área de augas abertas e o uso das zonas húmidas por estas galiñolas en Maine [26] e a abundancia relativa de exemplares en Saskatchewan.[27] No oeste de Nova York, os sitios de nidificación tiñan unha baixa porcentaxe de augas abertas en comparación con sitios ao azar,[16] e en Arizona usaban as zonas de augas abertas menos do que estas estaban dispoñibles.[14]
Os sitios de nidación das galiñolas da Carolina tiñan unha maior porcentaxe de vexetación emerxente, é dicir, que asoma por rba da superficie da auga, que sitios ao azar en pantanos do oeste de Nova York.[16] A cantidade de exemplares en zonas húmidas do nordeste de Dacota do Norte estaban correlacionadas positivamente de forma significativa (p<0,05)(r=0.45) coas hectáreas ocupadas pola vexetación emerxente viva. No leste e centro de Maine, as zonas húmidas usadas polas galiñolas da Carolina tiñan unha área significativamente maior (p=0,01) de vexetación emerxente que as non usadas.[26]
A densidade de vexetación emerxente nos hábitats destas aves varía e vai desde unha media de 121,9 talos/m2 nos territorios das galiñolas no noroeste de Iowa [25] a 333 talos/m2 en sitios do noroeste de Missouri usados durante a migración outonal.[24] No oeste de Nova York a cobertura era maior do 70% no 95% de niños de galiñola da Carolina. Ademais, os sitios de nidificación tiñan máis cuberta horizontal a 0,5 m sobre o nivel das augas que os sitios aleatorios.[16] Porén, a densidade de talos media nos territorios destas aves non era significativamente (p>0,05) diferente da dos sitios ao azar no noroeste de Iowa.[25]
A altura da vexetación emerxente no hábitat da galiñola da Carolina tamén varía desde 20 a 28 cm en primavera despois da alteración invernal no noroeste de Iowa[25] a 210 cm en áreas moi utilizadas pols galiñolas en Arizona.[14] En pantanos do oeste de Nova York, a altura da vexetación media nos sitios de nidificación era menor que nos sitios ao azar.[16] Porén, a altura media da vexetación emerxente nos territorios das galiñolas no noroeste de Iowa non era significativamente diferente (p>0,05) da altura en zonas ao azar.[25]
En Arizona, tanto a cobertura coma a altura da vexetación usada por esta especie variaba coas estacións. Conway suxeriu que as diferenzas probablemente reflectían a variada dieta destas aves.[14] A dispoñibilidade de hábitat en diferentes estacións é outra posible fonte de diferenzas estacionais no hábitat destas galiñolas.[10]
A extensión de vexetación leñosa que rodea as zonas húmidas de Dacota do Sur non estaba asociada significativamente (p=0,6) coa presenza de galiñolas da Carolina. Porén, en pantanos do oeste de Nova York, houbo unha relación significativa negativa (p=0,041) entre a porcentaxe de madeira inundada nun sitio e a abundancia relativa de galiñolas.[16]
As galiñolas da Carolina poden preferir algúns tipos de cobertura. En Arizona, o 65,3% das galiñolas utilizaban Typha domingensis, aínda que esta supoñía só o 16,5% da vexetación. Tamén usaban os Scirpus spp. e unha comunidade arbustiva mixta en proporción maior da que abundaban, mentres que evitaban os Tamarix chinensis e Pluchea sericea.[14] Na literatura indícase que evitan os sitios dominados por Lythrum salicaria. No leste e centro de Maine, as zonas húmidas utilizadas tiñan unha vexetación con significativamente máis vexetación de ericáceas (p=0,05), como Chamaedaphne spp., Myrica spp. e Kalmia spp..[26] En pantanos do noroeste de Iowa, aparece Sagittaria latifolia nos territorios das galiñolas da Carolina significantemente máis a miúdo (p<0,01) que nos sitios ao azar. Johnson e Dinsmore [25] consideraron que isto era probablemente o resultado de que ambas as especies (planta e ave) preferían sitios con condicóns similares. En maio e xuño en Wisconsin, detectáronse galiñolas significativamente (p<0,025) con máis frecuencia en áreas examinadas con Typha que en áreas con Carex spp.. Porén, no suroeste de Wisconsin durante a estación reprodutora, non había unha diferenza significativa (p=0,943) na densidade de galiñolas entre hábitats ocupados predominantemente por Typha spp., Catex spp. ou Scirpus spp..[23] Ademais, o uso que fan as galiñolas da Carolina de hábitats con Typha × glauca, Sparganium eurycarpum, Carex spp., Schoenoplectus fluviatilis e Schoenoplectus acutus var. acutus en pantanos do noroeste de Iowa reflectía xeralmente a dispoñibilidade destes hábitats.[25]
Existen diferenzas estacionais no uso do hábitat polas galiñolas da Carolina. No noroeste de Missouri en primavera, a probabilidade de detectar galiñolas da Carolina en plantas robustas emerxentes, como Typha spp. e Polygonum amphibium var. emersum, era 6 veces superior que a de detectalas alí en outono. Con todo, a dispoñibilidade de hábitats durante diversas épocas do ano non foi estudada.[24] Nun estudo realizdo no sueste de Missouri, as especies de plantas usadas polas galiñolas da Carolina durante a migación de outono e primavera diferían significativamente (p=0,005). Porén, o autor calificaba isto en relación coa súa obsevación de maiores diferenzas estacionais na dispoñibilidade de vexetación.[10]
Atópase xeralmente en comunidades de plantas dominadas por Typha spp.,[11][12][14][16][18][23] Carex spp.,[10][11][18][23][25] Scirpus spp.,[11][14][23][25] Polygonum spp.,[10][18] Juncus spp.,[10][18] Leersia oryzoides,[24] e Echinochloa spp.[10][24]
Fóra das zonas húmidas, encóntranse principalmente en áreas cultivadas durante a migración ou no período posterior á reprodución.Por exemplo, unha galiñola da Carolina foi observada a 4,8 km das zonas pantanosas nun campo cultivado de Iowa a metade de agosto. Un macho foi observado a menos de 300 m dunha zona húmida grande nun campo de soia (Glycine max) no noroeste de Iowa durante o período posterior á reprodución.[20] De xuño á metade de xullo, foron observados exemplares en granxas de Saskatchewan sementadas principalmente con trigo (Triticum aestivum).[27]
A galiñola da Carolina rexistrouse tamén en áreas arboradas asolagadas.[16][26] No oeste de Nova York, apareceron durante a estación reprodutora nun sitio en estudo onde o 26% da área era considerada "bosque inundado", e o 5% fora clasificado como "arbustivo/pantano arbustivo".[16] No leste e centro de Maine, observouse unha media de 2,1 exemplares en pantanos boscosos por cada 100 horas de observación durante a estación reprodutora.[26] Nun sitio non reprodutor (de agosto a abril) no suroeste de Arizona, esta ave foi atopada utilizando unha "comunidade arbustiva mixta" máis do esperado se nos baseamos na dispoñibilidade dese tipo de terreo.[14] Foron tamén observadas con pouca abundancia nun sitio con Pseudotsuga menziesii, Pinus ponderosa e Populus tremuloides na Columbia Británica.[28]
A temperatura pode tamén influír na abundancia desta especie. En Colorado, a temperatura media en abril estaba correlacionada negativamente (p<0,01) (r= -0,94) coa abundancia de galiñolas da Carolina. Nos sitios que tiñan temperaturas media en abril ≤ 6 °C, as galiñolas da Carolina eran máis bundantes que a especie estreitamente relacionada Rallus limicola, mentres que nos sitios máis cálidos a proporción das galiñolas da Carolina respecto dos R. limicola diminuíu.[11]
As densidades varían de 12 galiñolas/acre en Colorado [17] a 0,47 parella/ha en Indiana.[19] Unha media de 1,3 galiñolas/ha responderon a chamadas nos sitios estudados de Colorado.[11] Unha densidade similar de galiñolas atopouse no sueste de Wisconsin.[23] En Iowa, a densidade media en 2 anos e varos hábitats de pantano era de 1,3 parellas/ha.[25]
Factores que teñen que ver coa paisaxe, como a área de pantano, bordos do hábitat nos pantanos e o número de pantanos na rexión poden tamén influír na especie.
Aínda que as galiñolas da Carolina aparecían en pantanos de todos os tamaños, poden aparecer en grandes densidades en pantanos de tamaño medio. Estaban relacionadas positivamente de forma significativa (p≤0,01) coa área de zona hñumida total e área perimetral de superficie de auga no leste e centro de Maine [26] e estaban relacionados positivamente de forma significativa (p<0,05) coa área de zonas húmidas en Saskatchewan.[27] En Maine, a galiñola da Carolina utilizaba un 10% das zonas húmidas de 1,0 ha, do 40% ao 50% das zonas húmidas de 1 a 2 ha en tamaño, e o 20% das zonas húmidas maiores de 20 ha.[26] No oeste de Nova York, as galiñolas foron significativamente (p=0,007) máis abundantes en pantanos de 40 a 101 ha que nos pantanos menores (<40 ha) ou maiores (100-150nbsp;ha). Ademais, detectáronse niños máis frecuentemente nos pantanos de 40-81 ha.[16]
Tamén parecen preferir hábitats de bordo. A densidade de galiñolas da Carolina reprodutoras estaba significativamente (p<0,001) correlacionado (r=0,62) coa proporción perímetro:área dos pantanos do noroeste de Iowa. A distancia desde o centro dos territorios das galiñolas ao bordo do hábitat era tamén significativamente (p<0,005) menor que desde o centro dos territorios de Rallus limicola.[25] En Arizona, os bordos de hábitat estaban máis próximos ás áreas das que facían grande uso as galiñolas que os sitios aleatorios.[14]
A dinámica das zonas húmidas a unha grande escala pode afectar ás galiñolas da Carolina. Os índices da poboación de galiñolas a 3 "niveis de resposta" estaban correlacionados significativamente (p<0,01) (r≥0,70) co número de lagoas presentes na rexións de pozas de pradeira de Dacota do Norte en maio.[29]
Comen unha gran diversidade de alimentos. Os animais que adoita comer son caracois, crustáceos, arañas e insectos, principalmente escaravellos, grilos, moscas e libélulas.[30][31] Adoitan comer sementes de plantas como Polygonum spp., Scirpus spp., Carex spp. e Echinochloa spp..[15][30][31] As sementes da planta anual Zizania aquatica e Leersia oryzoides cómenas tamén en Estados Unidos.[30] Na literatura menciónanse como fontes relativamente importantes de alimentos para esta ave as Paspalum spp. e Oryza sativa no sueste de Estados Unidos. Outras plantas supoñen <5% da dieta das galiñolas da Carolina, entre elas Eleocharis spp., Lemnaceae, Potamogeton spp., Panicum spp., Spartina spp. e Distichlis spicata.[30]
Comen máis alimento vexetal en outono e inverno (68%–69%) que en primavera e verán (40%).[30] O material de plantas como Digitaria sanguinalis, Panicum dichotomiflorum e Setaria spp. apareceu con frecuencias substancialmente máis grandes e en moito maior volume en esófagos de galiñolas da Carolina cando se recolleu no sueste de Missouri durante a migración de outono que cando se recolleu en primavera. Ademais, os animais supoen un maior volume da dieta de primavera que da dieta de outono. O volume de material animal nos esófagos recollido en primavera estaba composto predominantemente de escaravellos adultos e caracois da familia Physidae.[31]
Varias especies comen ovos de galiñolas da Carolina como os visons americanos (Mustela vison), mofetas (Mephitidae), coiotes (Canis latrans), ictéridos do xénero Quiscalus, corvos (Corvus spp.) e garzas (Ardeidae).[15][18] Tamén se informou de predación de galiñolas da Carolina adultas por visóns americanos, coiotes e falcóns e curuxas.[13][18]
A galiñola da Carolina ou poliña americana (Porzana carolina) é unha pequena ave acuática gruiforme da familia dos rálidos. Vive en América do Norte. En Galicia pode aparecer como ave accidental. O nome do xénero, Porzana, deriva do termo sporzana da lingua veneciana que designaba este tipo de aves, e carolina refírese á colonia de Carolina dos tempos da colonización inglesa de Norteamérica.
Os adultos teñen unha lonxitude de entre 19 e 30 cm, coas partes superiores marróns con marcas negras, e cara e partes inferiores grises azuladas, e un barrado branco e negro nos flancos. Teñen un bico curto, groso e amarelo con marcas negras na face na base do bico e na gorxa. Os sexos son similares, pero os individuos novos carecen das marcas faciais negras e teñen unha cara abrancazada e peito beixe. Pesan entre 49 e 112 g.
O hábitat de reprodución da galiñola da Carolina son pantanos de gran parte de Norteamérica. Nidifican en sitios ben agochados entre densa vexetación. A femia xeralmente pon de 10 a 12 ovos, ás veces chega a poñer 18, nun niño con forma de cunca construído con vexetación do pantano. Os ovos non fan eclosión todos á vez. Ambos os pais incuban e alimentan as crías, as cales abandonan o niño pouco despois da eclosión e poden voar un mes despois.
Migran ao sur dos Estados Unidos e norte de Suramérica. Son aves errantes moi raras en Europa occidental (accidentais en Galicia), onde se poden confundir coa galiñola pinta. Porén, esta última ten sempre un peito con pintas, unha banda na parte superior da cabeza e un debuxo diferente nas ás.
Aliméntanse mentres camiñan ou nadan. Son omnívoras e comen sementes, insectos e caracois. Aínda que son aves máis fáciles de oír que de ver, ás veces poden verse camiñando preto de augas abertas. Son bastante comúns, malia a diminución nos últimos tempos dos hábitats axeitados para elas. A súa chamada é un asubío lento que soa ker-ui, ou un rincho descendente. Usar gravacións coa súa chamada incrementa moito as posibilidades de oíla e vela, xa que adoita investigar a fonte da chamada.
Il voltolino americano (Porzana carolina (Linnaeus, 1758)) è un uccello della famiglia dei Rallidi originario del Nordamerica[2].
Il voltolino americano misura 20–30 cm di lunghezza. Durante il periodo riproduttivo, presenta la gola e la faccia di colore nero; il breve becco è di colore giallastro. Il petto e la parte posteriore del collo sono grigi. Il dorso è bruno marmorizzato, mentre sull'addome vi è una serie di strisce bianche e nere. I sessi sono simili.
Gli esemplari immaturi e gli adulti al di fuori del periodo riproduttivo hanno una colorazione meno vistosa, color camoscio, e sono privi delle zone nere su gola o faccia. In questi esemplari la gola è bianca e il petto è marrone chiaro. Le zampe sono di colore verde giallastro. Mentre l'uccello cammina o è in volo, la coda viene tenuta eretta[3][4].
Il corpo del voltolino americano è forgiato per vivere negli ambienti paludosi. Il corpo, compresso lateralmente, permette all'animale di muoversi facilmente tra la fitta vegetazione. Le ali, corte e arrotondate, consentono un volo apparentemente debole, ma offrono una grande manovrabilità attraverso l'intrico della vegetazione. Le zampe robuste, munite di dita lunghe e sottili, permettono un passo sicuro e consentono all'animale di correre rapidamente anche nel fitto delle paludi. Sebbene preferisca camminare che volare, il voltolino americano è capace di volare per lunghe distanze, come dimostra, durante i suoi viaggi migratori, attraversando il golfo del Messico e il mar dei Caraibi[4][5].
Il voltolino americano occupa gran parte delle regioni temperate del Nordamerica; il suo areale si estende (a ovest) dai Territori del Nord-Ovest, a nord, fino alle estremità meridionali di Arizona e Nuovo Messico. A est il territorio di nidificazione si restringe, estendendosi dalle Province marittime del Canada fino al Maryland (USA), a sud. Quando le acque delle zone umide dei territori di nidificazione gelano, il voltolino americano si sposta verso sud per trascorrere l'inverno, occupando le regioni meridionali degli Stati Uniti dall'Arizona alla Florida, e anche il Messico. Inoltre, molti esemplari migrano attraverso il golfo del Messico e il mar dei Caraibi per svernare in Sudamerica. Le popolazioni presenti lungo le coste della California sono stanziali[5].
Il voltolino americano occupa le zone umide di acqua dolce di tutto il suo areale; nei territori di svernamento, comunque, si incontra anche nelle paludi di acqua salmastra. Gli habitat prediletti sono quelli che offrono una fitta copertura per la nidificazione, e sono costituiti soprattutto da zone umide di acqua dolce circondate da macchie di tife, carici e altre piante acquatiche di alto fusto[5].
In molte zone umide di tutto il suo areale è facile udire il richiamo del voltolino americano, ma l'uccello viene avvistato solo di rado. Così come altri Rallidi, il voltolino americano è una specie riservata, che trascorre gran parte del tempo tra la fitta vegetazione palustre. Se viene sorpreso, fugge al riparo volando con apparente debolezza, ma con un'ottima manovrabilità. Generalmente, tuttavia, il voltolino americano scivola silenziosamente verso un rifugio molto tempo prima che un possibile osservatore ne possa notare la presenza. Emette frequentemente i suoi richiami, fischiando e chiocciando in direzione dei propri simili, o addirittura in risposta al richiamo di altri Rallidi.
Il corteggiamento e l'accoppiamento avvengono agli inizi della primavera, quando gli uccelli ritornano ai siti di nidificazione. Le coppie, monogame, sono generalmente solitarie, e difendono il proprio territorio da possibili invasori intimorendoli con richiami o cacciandoli direttamente. Durante il corteggiamento i partner si lisciano le penne a vicenda e assumono particolari posture[5].
Tra i predatori del voltolino americano vi sono aironi, uccelli da preda e mammiferi carnivori opportunisti. I giovani esemplari sono particolarmente vulnerabili quando si allontanano in cerca di cibo senza la protezione di un genitore[6].
Una volta terminata la stagione riproduttiva, il voltolino americano assume un comportamento gregario e appena ha messo su uno strato di grasso si raggruppa in stormi numerosi per effettuare la migrazione. Gli spostamenti migratori avvengono quasi sempre di notte[5].
La dieta è costituita soprattutto da semi, insetti e chiocciole. I semi vengono raccolti da carici (Carex sp.), erbe (Calamagrostis sp., Bromus sp., Scoacloa sp., Poa sp., ecc.) o altre piante acquatiche. Le chiocciole e gli insetti vengono catturati sul terreno o immergendo il becco nel fango morbido e nel fitto della vegetazione[5].
Il nido è costituito da una bassa struttura a forma di cesta fatta di piante palustri, tenuta adesa agli steli delle piante circostanti. Generalmente è posto sopra l'acqua o nelle sue vicinanze, ma talvolta può essere costruito anche in una zona asciutta, tra i salici e le erbe che circondano gli specchi d'acqua[3].
Ciascuna covata è costituita da 10-12 (talvolta 6-18) uova brune ricoperte di macchioline più scure, deposte su due strati per farle entrare tutte in uno spazio relativamente piccolo. L'incubazione, effettuata da entrambi i genitori, dura 18-20 giorni, e inizia a partire dalla deposizione del primo uovo[5].
Le uova si schiudono in maniera asincrona, dato il diverso periodo di deposizione. I pulcini, precoci e ricoperti di piumino, vengono inizialmente accuditi da un solo genitore, dal momento che l'altro continua a occuparsi dell'incubazione delle uova non ancora schiuse. I giovani lasciano il nido poco dopo la schiusa e si procurano generalmente il cibo da soli, dopo aver visto come si fa osservando i genitori[6]. A 21-25 giorni di età i giovani si involano e le cure parentali terminano del tutto[5].
Il voltolino americano (Porzana carolina (Linnaeus, 1758)) è un uccello della famiglia dei Rallidi originario del Nordamerica.
De soraral (Porzana carolina) is een vogel uit de familie van rallen (Rallidae).
Deze soort komt voor van Alaska tot noordelijk Baja California en de zuidelijke Verenigde Staten en overwintert in West-Indië en noordelijk Zuid-Amerika.
Maskerikse (Porzana carolina) er en liten vannfugl av Riksefugle-familien. Slektsnavnet Porzana er avledet fra det venetiansk ordet for små skinner, mens Carolina refererer til Provinsen Carolina.
Voksne fugler er 19-30 cm[2][3][4] lange, med brun overside mørke merker, et blå-grått hode og underside, og svarte og hvite bånde på vingene. De har en kort, tykk gult nebb, med svarte markeringer i ansiktet innerst på nebbet og på halsen. Kjønnene er like, men unge maskerikser mangler de svarte ansiktsmerkene, og har et hvitt ansikt og kraftig bryst. De veier ca. 49-112 gram.
Maskeriksens ynglehabitatet er i myrer over store deler av Nord-Amerika.[5] De hekker på et godt skjult sted med tett vegetasjon. Hunnen legger vanligvis 10 til 12 egg, noen ganger så mange som 18, i et rede laget av vegetasjon fra myra. Eggene klekkes ikke samtidig. Begge foreldrene ruger og mater ungene, som forlater reiret kort tid etter klekking og er i stand til å fly i løpet av en måned. På grunn av artens trekkrute og utbredelse, er det denne amerikanske riksefuglen som dukker opp oftest på andre siden av Atlanteren.
De trekker til det sørlige USA og nordlige Sør-Amerika. Maskeriksen er en svært sjelden gjest i Europa, og har kun blitt observert en gang i Norge, da i Råde i Østfold, Juni 2017.[6] Dette var en syngende hannfugl og en av ytterst få vårobservasjoner fra Europa. Fuglen er påtruffet i overkant av tjue ganger på De britiske øyer, samt noen ganger på Azorene og det portugisiske fastlandet. Resten av funnene er tilfeldig plassert rundt i Vest-Europa.[7]
Maskerikse (Porzana carolina) er en liten vannfugl av Riksefugle-familien. Slektsnavnet Porzana er avledet fra det venetiansk ordet for små skinner, mens Carolina refererer til Provinsen Carolina.
Voksne fugler er 19-30 cm lange, med brun overside mørke merker, et blå-grått hode og underside, og svarte og hvite bånde på vingene. De har en kort, tykk gult nebb, med svarte markeringer i ansiktet innerst på nebbet og på halsen. Kjønnene er like, men unge maskerikser mangler de svarte ansiktsmerkene, og har et hvitt ansikt og kraftig bryst. De veier ca. 49-112 gram.
Maskeriksens ynglehabitatet er i myrer over store deler av Nord-Amerika. De hekker på et godt skjult sted med tett vegetasjon. Hunnen legger vanligvis 10 til 12 egg, noen ganger så mange som 18, i et rede laget av vegetasjon fra myra. Eggene klekkes ikke samtidig. Begge foreldrene ruger og mater ungene, som forlater reiret kort tid etter klekking og er i stand til å fly i løpet av en måned. På grunn av artens trekkrute og utbredelse, er det denne amerikanske riksefuglen som dukker opp oftest på andre siden av Atlanteren.
De trekker til det sørlige USA og nordlige Sør-Amerika. Maskeriksen er en svært sjelden gjest i Europa, og har kun blitt observert en gang i Norge, da i Råde i Østfold, Juni 2017. Dette var en syngende hannfugl og en av ytterst få vårobservasjoner fra Europa. Fuglen er påtruffet i overkant av tjue ganger på De britiske øyer, samt noen ganger på Azorene og det portugisiske fastlandet. Resten av funnene er tilfeldig plassert rundt i Vest-Europa.
Multimedia w Wikimedia Commons Kureczka karolińska (Porzana carolina) – gatunek ptaka z rodziny chruścieli (Rallidae) żyjący na otwartych mokradłach. Długość ciała 21-26 cm. Wierzch głowy oliwkowobrązowy. Na skrzydłach i grzbiecie czarne plamy. Maska czarna; policzki, przód szyi oraz górna część piersi szare. Brzuch biały. Boki biało i brązowo prążkowane. Pokrywy podogonowe białe. Dziób żółty, krótki. Kiedy chodzi podryguje krótkim ogonem. Hałaśliwa o zmroku.
Kureczka karolińska (Porzana carolina) – gatunek ptaka z rodziny chruścieli (Rallidae) żyjący na otwartych mokradłach. Długość ciała 21-26 cm. Wierzch głowy oliwkowobrązowy. Na skrzydłach i grzbiecie czarne plamy. Maska czarna; policzki, przód szyi oraz górna część piersi szare. Brzuch biały. Boki biało i brązowo prążkowane. Pokrywy podogonowe białe. Dziób żółty, krótki. Kiedy chodzi podryguje krótkim ogonem. Hałaśliwa o zmroku.
Zasięg, środowisko Wilgotne łąki i mokradła Ameryki Północnej. Zimuje od południowej części Ameryki Północnej do północnej części Ameryki Południowej, także widywana w Indiach Zachodnich.A sora (Porzana carolina) é uma ave aquática de pequeno porte da família Rallidae.
O nome do gênero Porzana tem origem nos termos venezianos para pequenas sanãs, e carolina se refere à Província da Carolina.[2] O nome "sora" provavelmente tem origem em uma língua nativo-americana.[3]
As soras adultas medem entre 19 e 30 cm de comprimento,[4][5][6] com marcas marrom-escuras por cima, coloração cinza-azulada na cabeça e na parte de baixo do corpo e barras pretas e brancas nos flancos. O bico, grosso e curto, é amarelo, com marcas pretas na base do bico e na garganta. Machos e fêmeas são similares. Os jovens não apresentam as marcas faciais pretas e têm uma cabeça mais esbranquiçada e peito amarelo-claro. Essas aves pesam entre 49 e 112 g[4] e a envergadura de asas mede entre 35 e 40 cm de comprimento.[7]
A sora é comum através da América do Norte, ocorrendo naturalmente em 49 estados dos Estados Unidos (exceto o Havaí), todas as dez províncias e dois territórios do Canadá. Fora dos Estados Unidos e do Canadá, a espécie é encontrada através da América Central, no Caribe, e no norte da América do Sul. A espécie foi registrada como vagante em Islândia, Grã-Bretanha, Portugal e no Lago Titicaca.
No Brasil, a sora foi registrada na APA de Maricá em 2015.[8]
A sora (Porzana carolina) é uma ave aquática de pequeno porte da família Rallidae.
Karolinasumphöna (Porzana carolina) är en liten fågel inom familjen rallar (Rallidae).
En adult karolinasumphöna är 18-21 cm lång.[2] Likt de andra rallarna har den en kort trekantsformad stjärt som den ofta bär uppåt. Undersidan av stjärten är ofta ganska tydligt tvåfärgad med en varmbeige centralt parti och vita yttre kanter. Den adulta fågeln har en mörkbrun ovansida med svarta fläckar och fina vita streck på ryggen. Ansiktet och undersidan är blågrått och den är vattrad i svartvitt på kroppssidorna. Den har en kort, kraftig och gul näbb, och svart teckning mellan ögat och näbbroten, och ner på strupen. Könen är lika medan juvenila individer saknar de svarta markeringarna i ansiktet som är vitaktigt och de har ett rödbrunt bröst.
Framförallt observeras den på grund av sina läten. Sången är en låg, ganska långsam vissling som stiger på slutet, "ku-vy". Denna vissling upprepas och kan höras lång. Ett annat läte är en drill som påminner om smådoppingens läte.[2]
Den skiljer sig morfologiskt från sin europeiska släkting, småfläckig sumphöna (Porzana porzana), då den senare alltid har ljusa fläckar på bröstet, en streckad hjässa, istället för det mörka centrala hjässband som karolinasumphönan har, och de har olika vingteckning. Småfläckig sumphöna har fina vita tvärband på tertialerna medan karolinasumphöna har mörka tertialer med ljusa kanter. Deras läten skiljer sig också åt.
Karolinasumphöna är en flyttfågel som häckar i lämpliga biotoper över merparten av Nordamerika från södra Alaska till södra USA.[3] Den övervintrar från södra USA till norra Sydamerika.[3] Den är en ovanlig gäst i Västeuropa. I Sverige har karolinasumphöna påträffats endast tre gånger, senast i Kråkberg utanför Mora i Dalarna i juli 1987.
Karolinasumphönans häckningsbiotop utgörs av våtmarker[4] där de bygger sina bon väl dolt i den täta undre vegetationen. Honan lägger vanligtvis 10- 12 ägg, ibland så många som 18, i det skålformade boet byggt av växtdelar. Båda föräldrarna ruvar äggen och matar ungarna. Äggen kläcks inte samtidigt och ungarna lämnar snabbt boet. De kan flyga inom en månad efter kläckningen.
Karolinasumphönan födosöker både på land och i vattnet och den är en allätare som främst lever av frön, insekter och sniglar.
De är ganska vanliga och anses inte hotade trots en minskning av lämpliga häckningsbiotoper. Internationella naturvårdsunionen IUCN kategoriserar populationen som livskraftig (LC).[1]
Wikimedia Commons har media som rör karolinasumphöna.
Porzana carolina là một loài chim trong họ Rallidae.[1] Cá thể trưởng thành dài từ 19–30 cm (7,5–11,8 in)[2][3][4], với phần trên của nâu đậm màu, mặt và phần dưới màu xanh xám, và các thanh màu đen và trắng ở hai bên. Họ có một hóa đơn màu vàng dày ngắn, có dấu màu đen trên mặt tại cơ sở của hóa đơn và trên cổ họng. Chim trống chim mái có màu lông tương tự nhau, nhưng ức chim non không có các dấu trên khuôn mặt màu đen và có một làn da trắng ức màu nâu vàng da bò. Loài này cân nặng khoảng 49–112 g (1,7–4,0 oz).[2]
Môi trường sinh sản của loài này là đầm lầy trên khắp Bắc Mỹ. [5] Chúng làm tổ trong một vị trí giấu kín trong thảm thực vật dày đặc. Con cái thường đẻ từ 10 đến 12 trứng, đôi khi nhiều như 18, trong một chén được chế tạo từ thảm thực vật đầm lầy. Trứng không nở cùng nhau. Cả hai bố mẹ ấp và nuôi trẻ, những người rời khỏi tổ sớm sau khi nở và có thể bay trong vòng một tháng.
Chúng di cư đến miền Nam Hoa Kỳ và miền Bắc Nam Mỹ. Sora là một kẻ lang thang rất hiếm hoi đến Tây Âu, nơi nó có thể bị lẫn lộn với gà nước lông đốm. Tuy nhiên, các loài sau này luôn luôn đốm trên ức. Một dải chỏm đầu và một mẫu cánh khác.
Chúng kiếm thức ăn khi đi bộ hay bơi lội. Chúng là động vật ăn thịt, ăn hạt, côn trùng và ốc sên. Mặc dù soras thường xuyên nghe thấy hơn là nhìn thấy, song đôi khi chúng lại nhìn thấy gần nước. Chúng khá phổ biến, bất chấp sự suy giảm môi trường sống thích hợp trong thời gian gần đây.
Porzana carolina là một loài chim trong họ Rallidae. Cá thể trưởng thành dài từ 19–30 cm (7,5–11,8 in), với phần trên của nâu đậm màu, mặt và phần dưới màu xanh xám, và các thanh màu đen và trắng ở hai bên. Họ có một hóa đơn màu vàng dày ngắn, có dấu màu đen trên mặt tại cơ sở của hóa đơn và trên cổ họng. Chim trống chim mái có màu lông tương tự nhau, nhưng ức chim non không có các dấu trên khuôn mặt màu đen và có một làn da trắng ức màu nâu vàng da bò. Loài này cân nặng khoảng 49–112 g (1,7–4,0 oz).
Môi trường sinh sản của loài này là đầm lầy trên khắp Bắc Mỹ. Chúng làm tổ trong một vị trí giấu kín trong thảm thực vật dày đặc. Con cái thường đẻ từ 10 đến 12 trứng, đôi khi nhiều như 18, trong một chén được chế tạo từ thảm thực vật đầm lầy. Trứng không nở cùng nhau. Cả hai bố mẹ ấp và nuôi trẻ, những người rời khỏi tổ sớm sau khi nở và có thể bay trong vòng một tháng.
Chúng di cư đến miền Nam Hoa Kỳ và miền Bắc Nam Mỹ. Sora là một kẻ lang thang rất hiếm hoi đến Tây Âu, nơi nó có thể bị lẫn lộn với gà nước lông đốm. Tuy nhiên, các loài sau này luôn luôn đốm trên ức. Một dải chỏm đầu và một mẫu cánh khác.
Chúng kiếm thức ăn khi đi bộ hay bơi lội. Chúng là động vật ăn thịt, ăn hạt, côn trùng và ốc sên. Mặc dù soras thường xuyên nghe thấy hơn là nhìn thấy, song đôi khi chúng lại nhìn thấy gần nước. Chúng khá phổ biến, bất chấp sự suy giảm môi trường sống thích hợp trong thời gian gần đây.
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