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Alosa pseudoharengus was formerly classified as Alosa pseudoharengus. Common names for A. pseudoharengus include alewife, gaspereau, sawbelly, kyak, kiack, river herring, and glut herring.
Alewives have some interesting cultural and historical connections. Alewives are the fish the Native Americans in New England buried with crops as fertilizer (Grosvenor, 1965). The silvery coating on the scales is sometimes used in making costume jewelry and is called pearl essence by the jewelry industry (Grosvenor, 1965).
We don't know much about how alewives might communicate. Their large eyes probably help them find other alewives, their prey, and stay alert for predators.
Communication Channels: tactile ; chemical
Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical ; electric
Alewives not listed as an endangered species, but in many places in their natural range, their habitat is threatened by dams along spawning rivers. On the other hand, their introduction into the Great Lakes and other areas resulted in declines in native fish in those areas.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
Fertilized eggs are about 0.9 mm in diameter. Three to five days after hatching, the larvae begin to feed. They slowly transform into juvenile fish and remain in fresh water until the fall. While in freshwater, young-of-the-year grow 1.5 to 5 inches (3.8 to 12.5 cm). Little is known about sub-adult life-history traits.
Alewives are considered a forage fish and have many predators. In freshwater, their main predators are burbot (Lota lota), lake trout (Salvelinus namaycush), eels (Anguillidae), bass (Micropterus), walleye (Sander vitreus), and whitefish (Scott and Crossman, 1998). Introduced predators include chinook and coho salmon. Little is known about the predators of anadromous alewives but their hatchlings have a high mortality rate. As few as one out of 80,000 will reach the sea (Scott and Scott, 1988).
Known Predators:
Alosa pseudoharengus has an overall silvery color with a grayish green back. A black spot at the eye level is directly behind the head. Adults have longitudinal lines that run along the scale lines above the midline of the body. Small specimens have a violet sheen on the sides while anadromous adults have a golden cast on their heads and upper parts. The scales are deciduous and the lateral line is not well-developed (Scott and Crossman, 1998). Coloration is generally similar to that of the skipjack herring, Alosa chrysochloris. Scales on the midline of the belly form scutes, creating a serrated surface (Trautman, 1957). Females are bigger than males and generally live longer. The body is strongly laterally compressed and relatively deep. The head is broadly triangular. Eyes are large and have well-developed adipose eyelids. The front of the jaw is thick and extends past the lower jaw when the mouth is closed. The maxillary extends to below the middle of the eye. A few small teeth are present on the premaxillary and mandible (Scott and Crossman, 1998). There are more than 30 gill rakers on the lower angle of the first gill arch (Trautman, 1957). The singular dorsal fin usually has 13-14 rays but may have 12-16. The caudal fin is forked. The anal fin is short and wide with 15-19 rays (usually 17-18). The pelvic fins are rather small and contain 10 rays. The pectoral fins are low on the sides and usually have 16 rays but may have as few as 14 (Scott and Crossman, 1998). There are a few physiological differences between anadromous and land-locked individuals. Anadromous specimens tend to be longer, ranging from 255 to 355 mm while land-locked species average 150 mm in length. Land-locked fish mature faster than anadromous ones (Daniels, 2001).
Range length: 100 to 355 mm.
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry
Sexual Dimorphism: female larger
Average mass: 110 g.
Young alewives have a very high mortality rate. Less than 1% survive to migrate into the sea (U.S. Department of Agriculture, 2004). Annual mortality for adult alewives is on the order of 70% per year. Most die during or shortly after the spawning season (U.S. Department of Agriculture, 2004). Few land-locked alewives live longer than 5 years (Smith, 1970).
Range lifespan
Status: wild: 10 (high) years.
Typical lifespan
Status: wild: 5 (high) hours.
For anadromous populations, much is known about their freshwater spawning habits, but little is known about movements within the ocean. Alewives spend most of their time in coastal waters and most are caught in water 56-100 m deep at about 4°C (Scott and Scott, 1988). Light sensitive, they tend to be in deeper waters during daylight hours. They also follow diel movements of zooplankton in the water column (Scott and Scott, 1988). Adults can withstand temperatures up to 25°C and young of the year can live in waters up to 30°C (Scott and Scott, 1988).
Freshwater populations spend most of their time in the deep waters of the lakes but come to the shallows and tributary streams in the spring to spawn (Trautman, 1957). The fish go to the deepest parts of the lakes to overwinter.
Range depth: 56 to 100 m.
Habitat Regions: temperate ; saltwater or marine ; freshwater
Aquatic Biomes: lakes and ponds; rivers and streams; coastal
Other Habitat Features: estuarine ; intertidal or littoral
Alosa pseudoharengus (Wilson, 1811) is an anadromous species, native to the Atlantic Ocean and the lakes and streams that drain to it from Newfoundland to North Carolina (Scott and Crossman, 1998). This includes the Gulf of St. Lawrence, the outer coast of Nova Scotia, the Bay of Fundy, and the Gulf of Maine (Scott and Scott, 1988). It is also present, although non-native, in all of the Great Lakes (USA), and many lakes in northern New York. In the Great Lakes, A. pseudoharengus was first caught in Lake Erie in 1931 off the coast of Nanticoke, Ontario, Canada. Populations then moved slowly upstream to the upper great lakes (Scott and Crossman, 1998). It was discovered in Lake Huron in 1933, Lake Erie in 1940, Lake Michigan in 1949, and Lake Superior in 1954 (Scott and Crossman, 1998). It is now abundant in Lake Huron and dominant in Lake Michigan. Alewives cannot dominate Lake Superior due to cold water and predation by lake trout (Salvelinus namaycush), nor can they dominate Lake Erie because the lake is too shallow to provide suitable overwintering grounds for large numbers of fish (Scott and Crossman, 1998). Several theories exist on how alewives could have become established in the Great Lakes. Scott and Crossman suggest that alewives may have been accidentally included in a batch of American shad (Alosa sapidissima) that were used to stock Lake Ontario. The alewives also could have migrated from Lakes Seneca and Cayuga in New York to the Great Lakes through the St. Lawrence River. A third argument for the current distribution is that alewives were native to Lake Ontario in small numbers but went unnoticed until the population explosion in 1873 (Daniels, 2001). Daniels (2001) argues against both the theory of introduction with stocked American shad and dispersal through canals. He argues against the canal introduction because the alewife floater, Anodonta implicata, is not found in the upper portions of canals or in Lake Ontario. Anodonta implicata is a mussel and a parasite of alewives (Daniels, 2001).
Biogeographic Regions: nearctic (Introduced , Native )
Little is known about the feeding habits of anadromous alewives (Scott and Scott, 1988). Adult land-locked fish eat mostly zooplankton, especially larger varieties such as copepods, cladocerans, mysids, and ostracods (Scott and Crossman, 1998). When they grow larger than 11.9 cm, they feed mostly on the benthic amphipod Pontoporeia (Scott and Scott, 1988). Some spawning adults eat small fish or fish eggs when in shallow waters (Scott and Crossman, 1998). Larval alewives eat mainly cladocerans and copepods.
Animal Foods: fish; eggs; aquatic crustaceans; zooplankton
Primary Diet: planktivore
Alosa pseudoharengus is now the most abundant planktivore in Lake Ontario and it is the main prey of salmonoids stocked into the great lakes (Klumb, Rudstam, and Mills, 2003). Its presence in the Great Lakes has caused the decline of many fish species due to competition.
There have been few studies published on alewife parasites (Scott and Scott, 1988). Anadromous populations host more species of parasites than land-locked populations. Alewives caught off the Atlantic coast were found to host the following parasites: acanthocephalans, cestodes, trematodes, copepods, and nematodes (Scott and Crossman, 1998). Parasites are rare in land-locked populations (Scott and Scott, 1988), but one important freshwater alewife parasite, the alewife floater, Anodona implicata, has been used to research the historical range of the alewife. Anodonta implicata is a mussel which is native to the tidal Hudson river and Delaware Rivers in New York (Daniels, 2001).
Commensal/Parasitic Species:
Alewives represent an important commercial fishery in the Atlantic Ocean. They are packaged fresh, smoked, salted, or pickled for human consumption and are often sold as “river herring.” Fishermen use weirs, traps, gill nets, and dip nets for alewives, which they consider one of the easiest fish to catch (Scott and Scott, 1988). Alewives have other uses, including pet food, lobster and snow crab bait, and processing into fishmeal and fish oil (Scott and Scott, 1988). The North American Fisheries Organization statistical bulletin includes alewives in the "other fish" category so no catch data are available (Scott and Scott, 1988). Alewives have not seriously been exploited as a fishery in the Great Lakes since these are small and too bony to eat. However, recently there has been a trend to use them for pet food and fish meal (Scott and Crossman, 1998).
Positive Impacts: food ; body parts are source of valuable material
Alewives have been considered a nuisance in the Great Lakes since their population explosion in 1873. Live fish tend to clog industrial intake pipelines and are “particularly obnoxious during periods of mass die-offs” because they can cause health hazards from the large numbers of dead fish in the spring (Scott and Crossman, 1998). Control measures, such as the introduction of coho salmon, Oncorhynchus kisutch, however, provide important sport fisheries for Lake Michigan (Scott and Crossman, 1998).
Since they feed mainly on planktonic and benthic organisms, alewives are particularly good at accumulating DDT (dichloro-diphenyl-trichloroethane) in their fatty tissues (Scott and Crossman, 1998). This bioaccumulation can make it dangerous for humans and other high-level predators to eat piscivorous fish, such as salmon, that feed primarily on alewives.
All alewives spawn in the spring. The young swim to sea in anadromous populations or to deeper water in lake populations in the fall (Grosvenor, 1965). For anadromous populations, the temperature of the river water determines the timing of spawning migrations upstream, so spawning happens first in lower latitudes. Spawning generally starts in April in the south and lasts until the end of May in upper latitudes (Scott and Crossman, 1998).
In all populations, females reach the spawning grounds first (Scott and Crossman, 1998) and older fish are the first to spawn (Grosvenor, 1965). The oldest fish recorded at spawning sites were 9-10 years old (Grosvenor, 1965). Spawning occurs in groups of 3 or in pairs (Scott and Crossman, 1998).
Mating System: polygynandrous (promiscuous)
Females broadcast their eggs simultaneously with males broadcasting sperm (U.S. Department of Agriculture, 2004). Although the eggs are adhesive at first and may stick to plants or rocks, they loose their adhesive qualities after a few hours and settle to the substrate (Scott and Scott, 1988). Alewives deposit their eggs over any type of substrate (U.S. Department of Agriculture, 2004). The number of eggs per female may be 10,000 to 12,000 (Scott and Crossman, 1998) or 48,000-360,000 (Scott and Scott, 1988).
In anadromous populations, adult alewives spend most of their lives at sea but spawn in streams above the influence of the tide. Although they cannot jump obstacles such as dams, they surmount rapids and fish runs migrating farther upstream than the closely related American shad (Scott and Crossman, 1998). Anadromous fish reach maturity at 3 years for males and 4 years for females (Scott and Crossman, 1998).
Land-locked populations mature at 2 years for males and 3 years for females. These fish move close to shallow beaches or up streams to spawn. They move on-shore at night and off-shore during the day. Adults leave the shallows immediately after spawning and have moved to deep water by late August (Scott and Crossman, 1998). Eggs hatch in 6 days at a mean water temperature of 60°F (15.6°C) and in 3 days at 72°F (22.2°C) (Scott and Crossman, 1998). Their maximum hatching success occurs at 20.8°C (Grosvenor, 1965).
Breeding interval: Alewives breed yearly.
Breeding season: Spawning occurs during the spring.
Range number of offspring: 10,000 to 360,000.
Range gestation period: 3 to 6 days.
Range age at sexual or reproductive maturity (female): 3 to 4 years.
Range age at sexual or reproductive maturity (male): 2 to 3 years.
Key Reproductive Features: seasonal breeding ; sexual ; fertilization (External ); broadcast (group) spawning; oviparous
Alewives do not have any parental investment in their young beyond spawning. The adults leave immediately after spawning in the spring and the young move to the open water in the fall.
Parental Investment: no parental involvement; pre-fertilization (Provisioning, Protecting: Female)
El gasparell o Alosa pseudoharengus és una espècie de peix de la família dels clupèids i de l'ordre dels clupeïformes present a la costa atlàntica des del Golf de Sant Llorenç i Nova Escòcia fins a Carolina del Nord, incloent-hi els rius. Ha estat introduït als Grans Llacs d'Amèrica del Nord (Ontario, Erie, Huron, Michigan i Superior).[4] Es comercialitza fresc, assecat, en salaó, fumat i congelat per a ésser fregit.[5]
Els mascles poden assolir 40 cm de llargària total i 200 g de pes.[6][4]
Els adults mengen peixets i gambes, i els exemplars immadurs es nodreixen de diatomees, copèpodes i ostràcodes mentre són als rius.[4] És depredat per Anguilla anguilla, Lophius americanus, Lota lota, Stizostedion vitreum, Oncorhynchus kisutch, Oncorhynchus mykiss, Oncorhynchus tshawytscha, Salvelinus namaycush, Cynoscion regalis, Morone saxatilis, Sander vitreus, Pomatomus saltator, Acanthocyclops vernalis, Dicyclops thomasi, Petromyzon marinus i Squalus acanthias.[7] És parasitat per cestodes, trematodes, copèpodes i acantocèfals.[4] Pot arribar a viure fins als 9 anys.[8] Es veu amenaçat per la sobrepesca, la contaminació de l'aigua i la construcció de dics que no poden remuntar en llurs migracions.[9]
El gasparell o Alosa pseudoharengus és una espècie de peix de la família dels clupèids i de l'ordre dels clupeïformes present a la costa atlàntica des del Golf de Sant Llorenç i Nova Escòcia fins a Carolina del Nord, incloent-hi els rius. Ha estat introduït als Grans Llacs d'Amèrica del Nord (Ontario, Erie, Huron, Michigan i Superior). Es comercialitza fresc, assecat, en salaó, fumat i congelat per a ésser fregit.
Els mascles poden assolir 40 cm de llargària total i 200 g de pes.
The alewife (Alosa pseudoharengus) is an anadromous species of herring found in North America. It is one of the "typical" North American shads, attributed to the subgenus Pomolobus of the genus Alosa.[4] As an adult it is a marine species found in the northern West Atlantic Ocean, moving into estuaries before swimming upstream to breed in freshwater habitats, but some populations live entirely in fresh water. It is best known for its invasion of the Great Lakes by using the Welland Canal to bypass Niagara Falls. Here, its population surged, peaking between the 1950s and 1980s to the detriment of many native species of fish. In an effort to control them biologically, Pacific salmon were introduced, only partially successfully. As a marine fish, the alewife is a US National Marine Fisheries Service "Species of Concern".
Alewife reach a maximum standard length (SL) of about 40 centimetres (16 in), but have a typical SL of about 30 centimetres (12 in).[2] The front of the body is deep and larger than other fish found in the same waters.
Alewife have bronze-colored heads and a grey-blue[5] to greyish green[6] dorsum. A humeral spot is often present.[6] The tongue does not bear teeth.[7] The peritoneum is light-colored with spots[5] to dusky-appearing,[6] an internal feature that distinguishes alewife from blueback herring (Alosa aestivalis), which have a dark peritoneum.[5] The otolith is shaped like a letter "L", unlike its hooked shape in A. aestivalis.[8] Additionally, the eye is larger than that of A. aestivalis;[7] the width of the eye often exceeds the length of the snout in A. pseudoharengus.[6]
Its common name is said to come from comparison with a corpulent female tavernkeeper ("ale-wife"),[9] or, alternatively, from the word aloofe,[10][11] possibly of Native American origin,[12] that was used to describe this fish in the seventeenth and eighteenth centuries.
In southwestern Nova Scotia, alewife are referred to as kiacks (or kyacks).[13] In Atlantic Canada it is known as the gaspereau, from the Acadian French word gasparot, first mentioned by Nicolas Denys. William Francis Ganong, New Brunswick biologist and historian, wrote:
Gaspereau, or Gasparot. Name of a common salt-water fish of Acadia (also called alewife), first used, so far as I can find, by Denys in 1672. Nowhere can I find any clue to its origin. It seems not to be Indian.[14]
Acadians named two rivers after the fish, the Gaspereau River in Nova Scotia and the Gaspereau River in New Brunswick.
Both anadromous and landlocked forms occur. The landlocked form is also called a sawbelly or mooneye (although this latter name is more commonly applied to Hiodon spp.) Adult alewife are caught during their spring spawning migration upstream by being scooped out of shallow, constricted areas using large dip nets. They are the preferred bait for the spring lobster fishery in Maine,[15] and are eaten by humans, usually smoked.
Alewife are known for their invasion of the Great Lakes by using the Welland Canal to bypass Niagara Falls. Alewife colonized the Great Lakes and became abundant mostly in Lake Huron and Lake Michigan. They reached their peak abundance from the 1950s through the 1980s. Alewife grew in number unchecked because the lakes lacked a top predator (lake trout were essentially wiped out around the same time by overfishing and the invasion of the sea lamprey).
For a time, alewife, which often exhibit seasonal die-offs, washed up in windrows on the shorelines of the Great Lakes. Various species of Pacific salmon (first coho, and later the Chinook salmon) were introduced as predators. Though marginally successful, this led to the development of a salmon/alewife fishery popular with many sport anglers.
In spite of such biological control methods, alewife remain implicated in the decline of many native Great Lakes species. It is also a common predator of numerous native and non-native zooplankton taxa (e.g. Bythotrephes longimanus,[16] Leptodiaptomus ashlandi, Limnocalanus spp.,[17] Leptodiaptomus minutus, Leptodiaptomus sicilis, and Leptodora kindtii[18]). Wells (1970) found that increases in population of alewife in the Great Lakes between 1954 and 1966 were associated with population declines in certain larger species of zooplankton, while an alewife die-off in 1967 was temporally related to population rebound in most of those species.[18]
Alewife populations have seen big declines throughout much of their range. Several threats have most likely contributed to their decline, including loss of habitat due to decreased access to spawning areas from the construction of dams and other impediments to migration, habitat degradation, fishing, and increased predation due to recovering striped bass populations.
In response to the declining population trend for alewives, the states of Massachusetts, Rhode Island, Connecticut, Virginia, and North Carolina have instituted moratoria on taking and possession.
In eastern Massachusetts, Alewife Brook flows through Arlington, Cambridge, and Somerville to the Mystic River. The brook gives its name to the Alewife Brook Parkway and the Alewife Brook Reservation. The Red Line (MBTA) of Boston's T ends at the Alewife station, so the name of this fish adorns the front of every northbound Red Line train. An extensive habitat restoration and education project, combined with a fish ladder with monitoring cameras, is yielding increasing numbers of alewife back in the improving Mystic River watershed.[19]
The alewife is a US National Marine Fisheries Service Species of Concern,[20] about which the National Oceanic and Atmospheric Administration, National Marine Fisheries Service, has some concerns regarding status and threats, but for which insufficient information is available to indicate a need to list the species under the US Endangered Species Act.
The alewife (Alosa pseudoharengus) is an anadromous species of herring found in North America. It is one of the "typical" North American shads, attributed to the subgenus Pomolobus of the genus Alosa. As an adult it is a marine species found in the northern West Atlantic Ocean, moving into estuaries before swimming upstream to breed in freshwater habitats, but some populations live entirely in fresh water. It is best known for its invasion of the Great Lakes by using the Welland Canal to bypass Niagara Falls. Here, its population surged, peaking between the 1950s and 1980s to the detriment of many native species of fish. In an effort to control them biologically, Pacific salmon were introduced, only partially successfully. As a marine fish, the alewife is a US National Marine Fisheries Service "Species of Concern".
Riverharingo aŭ falsa haringo (Alosa pseudoharengus) estas specio de la Klupeedoj. Estas anadromaj kaj terinternaj formoj. La fronto de la korpo estas profunda kaj pli granda ol aliaj fiŝoj troviĝantaj en tiuj samaj akvoj, kaj ties komuna nomo en angla ("ale-wife", kelnerino) devenas el supozata komparo kun supozata fortika kelnerino ("ale-wife").[1] En Atlantika Kanado ĝi estas konata kiel gaspereau. Pli surloke, en sudokcidenta Nova Scotia, ĝi estas nomata kiack (aŭ kyack).[2] En sudorienta Usono, vendita kaj uzata kiel allogaĵo por fiŝhokado, la fiŝo estas ofte menciata kiel "LY".
Riverharingo aŭ falsa haringo (Alosa pseudoharengus) estas specio de la Klupeedoj. Estas anadromaj kaj terinternaj formoj. La fronto de la korpo estas profunda kaj pli granda ol aliaj fiŝoj troviĝantaj en tiuj samaj akvoj, kaj ties komuna nomo en angla ("ale-wife", kelnerino) devenas el supozata komparo kun supozata fortika kelnerino ("ale-wife"). En Atlantika Kanado ĝi estas konata kiel gaspereau. Pli surloke, en sudokcidenta Nova Scotia, ĝi estas nomata kiack (aŭ kyack). En sudorienta Usono, vendita kaj uzata kiel allogaĵo por fiŝhokado, la fiŝo estas ofte menciata kiel "LY".
La pinchagua (Alosa pseudoharengus) es un importante pescado comestible de Norteamérica, perteneciente a la familia de los arenques.
La pinchagua crece hasta cerca de 30 cm. Casi todas los bancos de esta clase de pez, pasan varios años a lo largo de la costa atlántica de América del Norte, antes de ascender por las corrientes de agua dulce para desovar cada primavera en estanques o ríos lentos.
Harmaasilli tai kantasilli (Alosa pseudoharengus) on sillien heimoon kuuluva kala, joka ui vuosittain jokiin kutemaan.[1]
Laji kasvaa yleensä 30 senttimetrin pituiseksi, pisimmät tavatut yksilöt noin 40 senttimetrin mittaisia. Harmaasilli painaa korkeintaan 200 grammaa ja elää enintään 10 vuotta vanhaksi. Kalan kylki on hopeinen. Harmaasillillä on melko suurikokoiset silmät ja kapea ylöspäin suuntautunut suu. Evät ovat väriltään harmaanruskeita, vatsaevät punertavat hieman.[2]
Harmaasilli elää pääasiassa meri- tai murtovedessä, mutta aikuiset kalat vaeltavat vuosittain joelle ja järviin kutemaan. Laji elää Pohjois-Amerikan vesistöissä.[2][3]
Harmaasilli käyttää ravinnokseen katkarapuja ja pieniä kaloja. Poikaset syövät myös leviä ja muuta kasvillisuutta.[2]
Harmaasilli tai kantasilli (Alosa pseudoharengus) on sillien heimoon kuuluva kala, joka ui vuosittain jokiin kutemaan.
Le gaspareau (Alosa pseudoharengus) est un poisson appartenant au genre des aloses natif de l’océan Atlantique. Il ressemble au hareng, d'où son nom latin de « faux hareng ».
Gaspareau, gasparot, gaspereau, faux hareng, alewife, sawbelly, spreau, kyak, kiack, river herring, glut herring.
Alosa pseudoharengus est un petit poisson qui mesure habituellement entre 25 et 30 cm et dont le poids ne dépasse pas 400 grammes. Son corps est fortement comprimé latéralement. Des rangées d’écailles en dents de scie le long de la ligne latérale, au niveau de l’abdomen, lui donnent un aspect rugueux, d’où le nom commun « sawbelly »[1]. La coloration des flancs est argentée et iridescente, quand fraîchement pêché, et celle du dos est gris-vert. Les individus revenant de la mer peuvent avoir des reflets dorés ou cuivrés. Ce poisson est caractérisé par la présence d’une tache noire derrière les branchies juste au niveau de l’œil. Il est également possible d’observer plusieurs lignes noires au-dessus de la ligne latérale chez les adultes.
Le gaspareau a des yeux relativement gros avec des paupières adipeuses bien développées. Ses nageoires sont à rayons mous. La nageoire dorsale peut avoir 12-18 rayons; l’anale est plutôt courte et peut avoir 15-20 rayons; et la caudale est fourchue. Les nageoires pelviennes et pectorales sont plutôt petites et contiennent environ 10 rayons et les pectorales sont basses sur les côtés et contiennent généralement 14-16 rayons.
On remarque que le péritoine de Alosa pseudoharengus est habituellement pâle, alors qu’il est plutôt noirâtre chez l’alose d’été (Alosa aestivalis), une espèce apparentée. Cette caractéristique peut servir à différencier ces deux espèces qui possèdent une apparence et une biologie très semblables[2].
Le gaspareau est une espèce facultativement anadrome. L'anadromie consiste à passer la majeure partie de la vie adulte en mer et à remonter en eau douce seulement pour frayer. Alosa pseudoharengus est une espèce native de l’Amérique du Nord et largement répartie le long de la côte atlantique dans l’océan ainsi que dans les lacs et rivières, en passant par le sud de Terre-Neuve jusqu’à la Caroline du Sud, en incluant le fleuve Saint-Laurent. Plus précisément, dans les provinces maritimes, on retrouve l’espèce en grand nombre dans les rivières Miramichi, Margaree, LaHave, Tusquet, Shubenacadie et Saint-Jean[2]. On la retrouve également, mais plutôt rarement, dans la rivière Restigouche et la région de la baie des Chaleurs[2]. Depuis le printemps 2021, le retour de cette espèce a été constaté dans les eaux du lac Mattawamkeag dans le comté d'Aroostook (au nord du Maine), où il aurait été favorisé par l’arasement de barrages hydroélectriques sur les bras est et ouest de la rivière Mattawamkeag[3] . Il existe aussi quelques populations introduites confinées en eau douce dans plusieurs lacs de l’Ontario et de l’État de New York.
En milieu marin, on retrouve généralement le gaspareau dans les eaux côtières, jusqu'à une profondeur de 100 mètres[4]. À une telle profondeur, la température de l’eau est de 4 °C. Dans les eaux douces, le gaspareau passe la majeure partie de son temps en eau profonde, mais il fraye dans les eaux peu profondes. L’adulte peut supporter des températures aussi élevées que 25 °C, alors que le juvénile peut vivre jusqu’à 30 °C[5].
On retrouve également l’espèce de façon importante dans les Grands Lacs, où elle semble s'y être dispersée à partir du lac Ontario, de 1930 à 1950[2]. Considérée à l'origine comme une espèce envahissante, elle y est désormais appréciée depuis qu'on a introduit un prédateur, le saumon du Pacifique, lui-même apprécié pour la pêche [6]. Aujourd'hui, une autre espèce envahissante, la carpe asiatique, menace les populations de gaspareau dans les Grands Lacs [6].
La fraie de Alosa pseudoharengus s’effectue au printemps et semble être déclenchée par la température de l’eau. Ainsi, les populations plus au sud fraient plus tôt au printemps. En effet, en Caroline du Sud, le gaspareau remonte les rivières en mars-avril, lorsque la température de l’eau atteint environ 8 °C, tandis qu’au Nouveau-Brunswick la remontée se fait plutôt vers mai-juin[2]. Les populations d’eau douce vivant en eau profonde dans les lacs, remontent vers les rivages, ruisseaux ou rivières et fraient à partir de juin, lorsque la température de l’eau atteint environ 10 °C. La fraie a lieu en eaux calmes et peu profondes. Les femelles peuvent pondre de 48 000 à 360 000 œufs; les plus grosses produisant plus d’œufs. Les œufs fécondés mesurent environ 1 mm de diamètre et sont adhésifs pour quelques heures. Les femelles confinées aux eaux douces sont beaucoup plus petites et peuvent pondre une quantité de l’ordre de 12 000 œufs. L’éclosion s’effectue après environ 3 à 6 jours, selon la température d’incubation. La température d’incubation optimale se situe à environ 20 °C et la survie des œufs décroît significativement avec l’augmentation de la température. À leur sortie, les larves mesurent environ 4 mm[2]. La plupart des jeunes quittent leur cours d’eau natal vers août-septembre. L’adulte ayant survécu lors de la reproduction retourne en mer peu de temps après la fraie. Les jeunes gaspareaux s’alimentent habituellement de trois à cinq ans en mer avant de se reproduire. Les individus d’eau douce atteignent leur maturité sexuelle plus rapidement (2-3 ans)[5].
Le gaspareau se nourrit essentiellement de zooplancton (amphipodes, copépodes et mysides), mais aussi de petits poissons et d’œufs de poissons. Il choisit de préférence le zooplancton de grande taille. Dans les milieux d’eau douce, les larves de gaspareau se nourrissent surtout de cladocères. Ces derniers représentent 75 % de leur alimentation[4]. Les larves sont très sélectives dans le choix de leurs proies, au contraire des gaspareaux adultes. Jusqu’à l’atteinte d’une taille de 11,9 cm, les gaspareaux d’eau douce préfèrent le zooplancton, après quoi ils choisissent surtout des amphipodes benthiques tel que Pontoporeia[5]. Étant sensibles à la lumière, les gaspareaux pratiquent une migration verticale journalière qui leur permet de suivre les populations de zooplancton. Les gaspareaux se nourrissent peu ou pas du tout pendant la période de fraie.
En eau douce, les gaspareaux sont la proie de plusieurs prédateurs tels que l’anguille, la lotte commune, le touladi, l’achigan et le doré. Il est estimé que seulement un jeune poisson sur 80 000 œufs pondus survit assez longtemps pour quitter la frayère[4]. Ce taux de mortalité élevé est entre autres dû à la prédation. Les prédateurs du gaspareau en milieu marin sont peu connus. Par contre, il est probable que lors des migrations, donc lorsque leur abondance est importante, ils seraient la proie d’oiseaux de mer et de poissons prédateurs tels que le saumon de l’Atlantique et le bar rayé.
Dans les Grands Lacs, les gaspareaux ont contribué au déclin de plusieurs espèces de poissons en raison de la compétition. De plus, la pression de prédation causée par le gaspareau sur les larves de poissons peut avoir une influence sur le recrutement des espèces[4].
Les parasites du gaspareau comprennent une espèce d’acanthocéphale (Echinorhynchus acus) et une espèce de cestode (Rhynchobothrium imparispine), ainsi que certains trématodes, nématodes et copépodes[4]. Il existe aussi une espèce de moule (Anodonta implicata), dont la forme larvaire, nommée glochydium, est un parasite du gaspareau. Les glochydia s’attachent aux branchies et aux nageoires du gaspareau pour toute la durée de leur phase larvaire[7]. D’autre part, certains cas de nécrose érythrocytaire, une infection virale du sang chez les poissons, ont été rapportés chez des gaspareaux anadromes du Maine et du Nouveau-Brunswick[4].
Au Canada, la pêche commerciale des gaspareaux est importante dans les rivières Saint-Jean et Miramichi au Nouveau-Brunswick, ainsi que dans les rivières Gaspereau, Margaree, Mersey, Tusket et Shubenacadie en Nouvelle-Écosse. Ce poisson est considéré comme l’une des espèces les plus faciles à attraper. Le gaspareau est difficilement différentiable de l’alose d’été (Alosa aestivalis) au niveau de la biologie et de l’apparence, ce qui fait en sorte que les statistiques de pêche canadiennes combinent ces deux espèces. En 1983, la valeur de cette pêche commerciale était de 940 000 $ dans les provinces maritimes, pour un débarquement total de 4 125 tonnes de gaspareau[2]. Les gaspareaux sont mis en marché pour la consommation humaine (frais, congelés, fumés, salés ou marinés), mais peuvent aussi être mis en conserve pour la nourriture d’animaux domestiques. Ils sont aussi utilisés comme appâts dans la pêche au homard et au crabe des neiges. La chair des gaspareaux est blanche et douce, mais elle contient de nombreuses arêtes.
Le gaspareau sont considérés comme étant une espèce nuisible dans les Grands Lacs. Il n'est pas prisé pour la consommation, étant donné sa petite taille et ses nombreuses arêtes. Il peut boucher les tuyaux d’alimentation d’eau industrielle. Il peut aussi causer des problèmes de santé publique durant les périodes de mortalité massive. Une mesure de contrôle mise en place pour répondre à ce problème est l’introduction du saumon coho (Oncorhynchus kisutch), un prédateur important du gaspareau. Cela contribue aussi à l’augmentation de la pêche sportive dans ce secteur[5].
Le gaspareau (Alosa pseudoharengus) est un poisson appartenant au genre des aloses natif de l’océan Atlantique. Il ressemble au hareng, d'où son nom latin de « faux hareng ».
Alosa pseudoharengus (Wilson, 1811) è un pesce osseo marino e d'acqua dolce della famiglia Clupeidae.
È endemico dell'Oceano Atlantico nordoccidentale, si trova lungo le coste atlantiche nordamericane tra la Nuova Scozia (Canada) e la Carolina del Nord (USA) nonché nei corsi d'acqua tributari di questa area. Ci sono popolazioni che passano tutta la vita in acqua dolce nel Lago Cayuga e nel Lago Seneca nello Stato di New York. È stata introdotta (o meglio transfaunata) nel lago Ontario da cui si è diffusa nel resto dei Grandi Laghi[1] con effetti dannosi sull'ittiofauna autoctona e sulle industrie legate alla pesca[2].
Si tratta di una specie anadroma che nell'epoca riproduttiva risale i fiumi per la deposizione delle uova. Le popolazioni lacustri risalgono i fiumi tributari del lago in cui vivono. In mare vive in prossimità degli estuari, senza avventurarsi lontano dagli sbocchi d'acqua dolce. Anche piccoli ruscelli possono essere idonei per la riproduzione[1].
L'aspetto di questo pesce è simile agli altri membri del genere Alosa, con corpo abbastanza compresso ai lati e una carena ventrale di scaglie appuntite. Nei giovanili sono presenti piccoli denti all'estremità delle mascelle. L'occhio è piuttosto grande, il suo diametro è maggiore della lunghezza del muso. La colorazione del pesce vivo è argentea con riflessi verdastri sul dorso e una macchia rotondeggiante scura dietro l'opercolo[1].
La taglia media è sui 30 cm, la massima di circa 40 cm. Il peso massimo noto è di 200 grammi[1].
Gli adulti si alimentano di piccoli crostacei e pesci, i giovanili in acqua dolce predano crostacei ostracodi e copepodi nonché alghe diatomee[1].
Si riproduce nei tratti fluviali a corrente moderata. Dopo la riproduzione ritornano immediatamente in mare. I giovanili rimangono nel luogo di nascita fino a che non raggiungono 1 cm di lunghezza. La migrazione verso il mare dei nuovi nati avviene in autunno[1].
Questa specie ha una certa importanza per la pesca commerciale sia per il consumo umano che come esca per i crostacei e, talvolta, come cibo per animali domestici[1].
Sebbene le popolazioni introdotte nei Grandi Laghi siano abbondanti nell'areale naturale questa specie risente della sovrapesca, dell'inquinamento idrico e della presenza di sbarramenti fluviali che ostacolano le migrazioni riproduttive[1].
Alosa pseudoharengus (Wilson, 1811) è un pesce osseo marino e d'acqua dolce della famiglia Clupeidae.
De Amerikaanse rivierharing (Alosa pseudoharengus) is een straalvinnige vis uit de familie van haringachtigen (Clupeidae), orde haringachtigen (Clupeiformes),[2][3] die voorkomt in de binnenwateren van Noord-Amerika en het noordwesten en het westen van de Atlantische Oceaan.
De Amerikaanse rivierharing kan maximaal 40 cm lang en 200 gram zwaar worden. De hoogst bekende leeftijd is 8 jaar. Van de zijkant gezien heeft het lichaam van de vis een normale vorm, van boven gezien is de vorm het best te typeren als gedrongen. De kop is min of meer recht. De vis heeft één rugvin en één aarsvin.
De Amerikaanse rivierharing komt zowel in zoet, zout als brak water voor en is gebonden aan een gematigd klimaat. De soort is voornamelijk te vinden in rivieren, kustwateren (zoals estuaria, lagunes en brakke zeeën), zeeën en meren. De diepte waarop de soort voorkomt is 5 tot 145 m onder het wateroppervlak.
Het dieet van de vis bestaat zowel uit planten als dieren. Hij jaagt op macrofauna en vis.
De Amerikaanse rivierharing is voor de visserij van aanzienlijk commercieel belang. De soort komt niet voor op de Rode Lijst van de IUCN.
Bronnen, noten en/of referentiesDe Amerikaanse rivierharing (Alosa pseudoharengus) is een straalvinnige vis uit de familie van haringachtigen (Clupeidae), orde haringachtigen (Clupeiformes), die voorkomt in de binnenwateren van Noord-Amerika en het noordwesten en het westen van de Atlantische Oceaan.
Multimedia w Wikimedia Commons Aloza tęczowa[3], aloza wielkooka[3] (Alosa pseudoharengus) – gatunek ryby z rodziny śledziowatych (Clupeidae).
Północno-zachodni Atlantyk od Zatoki Św. Wawrzyńca i Nowej Szkocji po Karolinę Północną, oraz jeziora Seneca i Cayuga w stanie Nowy Jork. Introdukowana w jeziorze Ontario rozprzestrzeniła się po wszystkich Wielkich Jeziorach.
Tworzy stada, zazwyczaj w pobliżu ujść rzek, do których wchodzi na tarło. Zazwyczaj przebywa na głębokości 56–110 m (maksymalnie 145 m).
Osiąga maksymalnie 40 cm (zazwyczaj 30 cm) długości i 200 g masy ciała. Ciało umiarkowanie spłaszczone, na brzuchu wyraźny kil z łusek. Żuchwa wystaje poza szczękę, z przodu pyska niewielkie zęby zanikające z wiekiem. Średnica oka większa niż długość pyska. Wyrostki filtracyjne na dolnej części pierwszej pary łuków skrzelowych wyrastają z wiekiem w liczbie 38–44. W płetwach brzusznych 9 promieni.
Ubarwienie grzbietu szarozielone. Za głową ciemna plama. Wnętrze jamy otrzewnej srebrzyste.
Młode osobniki w rzekach żywią się okrzemkami, widłonogami i małżoraczkami. Dorosłe zjadają krewetki i małe ryby.
Drapieżnikami są sandacz amerykański, bass małogębowy, Pomoxis, pstrągi oraz rekiny i minogi. Pasożytami są kolcogłowy, tasiemce, przywry i widłonogi.
Dojrzewa płciowo przy długości powyżej 11 cm w wieku 2–5 lat, populacje słodkowodne dojrzewają wcześniej niż słonowodne. Trze się od III do VIII. Na tarło migruje w górę rzek, trze się w jeziorach i wolnych odcinkach rzek. Również populacje jeziorowe migrują do dopływów. Wkrótce po tarle tarlaki schodzą do morza lub jeziora. Tarło odbywa się zazwyczaj wieczorem przy temperaturze nieprzekraczającej 27,8 °C. Ikra jest pelagiczna okrągła, gładka, nie lepka. Żółtko jest ziarniste, jasne, bursztynowe do żółtego, przezroczyste. W temperaturze 7 °C inkubacja trwa 15 dni, w temperaturze 15 °C 6 dni, w temperaturze 21 °C 3 i pół, a przy 28 °C 2 dni.
Larwy po wykluciu pozostają w pobliżu tarlisk. Po 1 lub 2 tygodniach po wykluciu, przy długości około 10 mm, formują stada. Do morza schodzą latem i jesienią, czasem w listopadzie i grudniu.
Ma znaczenie w rybołówstwie. czasem łowiona przez wędkarzy. Sprzedawana świeża, solona, wędzona lub mrożona. Czasem wykorzystywana do połowu homarów i krabów, oraz do produkcji karmy dla zwierząt.
Nadmierne połowy, zanieczyszczenie wód i zabudowa rzek doprowadziły do spadku jej liczebności.
Aloza tęczowa, aloza wielkooka (Alosa pseudoharengus) – gatunek ryby z rodziny śledziowatych (Clupeidae).
Сіроспинка (Alosa pseudoharengus) — північноамериканська риба родини оселедцевих. Вид включає як анадромні (прохідні), так і цілком прісноводні форми. Передня частина тіла глибша і ширша, ніж у інших риб, знайдених в тому ж районі, що і надало їй англійську назву англ. alewife — від порівняння її з вагітною жінкою. Ця риба в минулому використовувалася як приманка для полювання на омарів, зараз вона використовується для споживання в їжу людиною, зазвичай копченою. Її виловлюють протягом міграції по річкам, використовуючи великі тенета, що відловлюють риб на мілині.
Сіроспинка (Alosa pseudoharengus) — північноамериканська риба родини оселедцевих. Вид включає як анадромні (прохідні), так і цілком прісноводні форми. Передня частина тіла глибша і ширша, ніж у інших риб, знайдених в тому ж районі, що і надало їй англійську назву англ. alewife — від порівняння її з вагітною жінкою. Ця риба в минулому використовувалася як приманка для полювання на омарів, зараз вона використовується для споживання в їжу людиною, зазвичай копченою. Її виловлюють протягом міграції по річкам, використовуючи великі тенета, що відловлюють риб на мілині.
Alosa pseudoharengus (Wilson, 1811)
Синонимы
Сероспинка[2], или элевайф[2] (лат. Alosa pseudoharengus) — вид лучепёрых рыб из семейства сельдевых. Обитают в морской, солоноватой и пресной воде заливов, озёр и речек[1][3].
Сероспинка — это вид проходных рыб, родом из Атлантического океана и озёр и речек штатов от Северной Каролины до Ньюфаундленда, впадающих в него. Обитает у побережья наружных берегов Новой Шотландии, заливах Фанди и Мэн, а также встречается во всех Великих Озёрах США и во многих озёрах северного Нью-Йорка[3].
Длина тела взрослых рыб обычно около 10—30 см, реже до 40 см, масса — 110—200 грамм[4][3]. Продолжительность жизни около 9 лет[4]. Самки крупнее самцов и в основном живут дольше[3]. Тело серебристого цвета с серовато-зелёной спиной. Чёрное пятно находится на уровне глаз за головой. У взрослых особей имеются продольные линии, которые проходят по середине тела. Меньшие особи имеют фиолетовый отблеск по бокам, тогда как у крупных проходных рыб золотистый оттенок на голове и верхней части тела. Чешуя легко опадающая, боковая линия слабо выражено. На брюхе хорошо выражен киль[3]. Окраска схожа с окраской зеленоспинки[3]. Проходные особи длиннее (25,5—35,5 см), чем озёрные (около 15 см). Озёрные рыбы созревают раньше[3].
Тело сильно приплюснутое и сравнительно высокое. Голова широко треугольная. Глаза большие и имеют хорошо развитые жировые веки. Спереди верхняя челюсть толстая. На нижней челюсти и предчелюстной кости есть зубы, но их немного. Более 30 жаберных тычинок расположены на нижней части первой жаберной дуги[3].
В спинном плавнике обычно 13—14 мягких лучей, хотя может быть 12—16 лучей. Хвостовой плавник вильчатый. Анальный плавник короткий и широкий, 15—19-лучевый (обычно из 17—18 лучей). Брюшные плавники маленькие и состоят из 10 лучей. Грудные плавники с 14—16 лучами, расположены низко [3].
Рыбы проводят большее время в прибрежных водах, в основном на глубине 56—100 метров, где температура воды достигает приблизительно 4 °C, хотя взрослые особи способны прожить в воде температурой 25 °C, а годовалый молодняк — 30 °C. Они очень чувствительны к температуре воды, в дневное солнечное время опускаются глубже. Рыбы следят за передвижением своей потенциальной добычи — зоопланктоном[3].
Пресноводные популяции проводят основное время в глубоководье населяемых озёр, весной поднимаясь на мелководье и в притоки речек для метания икры. В зимнее время рыбы опускаются в глубочайшие места озёр[3].
На жабрах паразитирует Clavellisa cordata — вид эктопаразитических веслоногих ракообразных[5].
Сероспинка, или элевайф (лат. Alosa pseudoharengus) — вид лучепёрых рыб из семейства сельдевых. Обитают в морской, солоноватой и пресной воде заливов, озёр и речек.
灰西鯡為輻鰭魚綱鲱形目鲱科的其中一種，分布於北美洲加拿大新斯科細亞省、聖羅倫斯河至美國北卡羅來納州淡水、半鹹水及鹹水水域，棲息深度5-145公尺，體長可達40公分，棲息在沿海半鹹水水域，為迴游性魚類，繁殖期時迴游至淡水溪流產卵，屬肉食性，以魚類、橈腳類、甲殼類為食，可做為食用魚。
分類 界 : 動物界 Animalia 門 : 脊索動物門 Chordata 亜門 : 脊椎動物亜門 Vertebrata 綱 : 条鰭綱 Actinopterygii 目 : ニシン目 Clupeiformes 科 : ニシン科 Clupeidae 亜科 : ニシンダマシ亜科 Alosinae 属 : ニシンダマシ属 Alosa 亜属 : Pomolobus 種 : エールワイフ A. (P.) pseudoharengus 学名 Alosa pseudoharengusエールワイフ(Alewife、Alosa pseudoharengus)はニシン科に属する魚類の一種。両側回遊型と陸封型がおり、陸封型はsawbelly・mooneyeとも呼ばれる（mooneyeはヒオドン科の魚類に対しても用いられる）。同じ水域に生息する魚と比べると、大きく、体高が高いことで区別できる。この体型から"太った女将"を意味する"ale-wife"と名付けられた[1]。カナダ大西洋州ではgaspereau、ノバ・スコシア州南西部では kiack または kyack と呼ばれる[2]。
ロブスター・タラ・サバ漁などの餌として好まれるほか、食用にもなる[3]。
本種は典型的な北米産シャッド（Pomolobus亜属）の一つである[4]。
最大で全長40cmに達する。成体は群れを作り、主に沿岸や河口で過ごす。春には川を遡り、流れの緩やかな場所で産卵する。産卵後には海に戻るが、40-60%の個体は死亡する。寿命は10年ほどで、生涯に2-3回産卵するとみられる。稚魚は微生物を食べて成長し、夏から秋にかけて海に降りる[3][5]。
ウェランド運河を通ることでナイアガラ滝を迂回して五大湖に侵入した[6]。ヒューロン湖・ミシガン湖で大増殖し、1950-1980年代にピークに達した。これは乱獲とウミヤツメの侵入により、頂点捕食者のレイクトラウトがほぼ消失していたことに起因する。この時代、本種の季節的な大量死により、湖岸には多数の死骸が漂着していた。これを制御するためにギンザケ・マスノスケなどの太平洋産サケが導入され、サケ/エールワイフ群集が成立することとなった[3]。これは釣り人には喜ばれたが、一方で多くの在来種の減少を招いている。
元々の生息地では急激に減少している。要因は様々だが、ダム建設による繁殖地の喪失・乱獲などが挙げられる[7]。
エールワイフ(Alewife、Alosa pseudoharengus)はニシン科に属する魚類の一種。両側回遊型と陸封型がおり、陸封型はsawbelly・mooneyeとも呼ばれる（mooneyeはヒオドン科の魚類に対しても用いられる）。同じ水域に生息する魚と比べると、大きく、体高が高いことで区別できる。この体型から"太った女将"を意味する"ale-wife"と名付けられた。カナダ大西洋州ではgaspereau、ノバ・スコシア州南西部では kiack または kyack と呼ばれる。
ロブスター・タラ・サバ漁などの餌として好まれるほか、食用にもなる。
