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Phaethornis guy, commonly known as the Green Hermit, is a member of the Trochilidae (Hummingbird) family. It is sometimes also called the Guy’s Hermit (Stiles and Skutch 1989). Two subspecies have been documented, the Phaethornis guy guy, which occurs in Trinidad, and P. guy coruscus, who’s range stretches from Costa Rica to W Columbia and SE Peru (Snow 1977, Stiles and Skutch 1989). Both prefer to live in wet mountain forest. They are slightly over 15 cm in length and weigh approximately 6 grams. Males are a dark, iridescent green with black tail feathers that are tipped in white. Females are a more dusky green with grey underparts. Both have long, curved bills. Their primary source of food is nectar. They are also known for their lekking behavior, in which males congregate and display for the purpose of attracting a mate. They have small nests made of plants, spider webs, and treefern scales, and typically nest between February and September in Costa Rica (Stiles and Skutch 1989).
Preferred habitat is the edges of forests and forest understory areas, although it has also been found foraging in coffee or cocoa plantations (Snow 1974). May occasionally visit sub-canopy areas in search of Columnea flowers. Leks occur in understory of mountain ridges (Stiles and Skutch 1989).
P. guy are considered to be fairly large for hummingbirds, at slightly over 15 cm and 6 grams. Their most distinctive feature is their tail, which is composed of long feathers with white tips for both males and females. Males typically have slightly shorter and more pointed tails than females (Stiles and Skutch 1989). Both males and females also have a unique bill, which is long and downward curved. It is black on the top and red on the bottom (Stiles and Skutch 1989). The male is a dark iridescent green, which darkens to a deep blue (Stiles and Skutch 1989). Males have short narrow stripes on their faces that become less prominent, eventually disappearing, as they grow older (Snow 1974). Females differ from males in that their heads are dusky green with buff facial stripes. Young look very similar to females, and do not have full adult plumage for 2 years (Stiles and Skutch 1989).
Phaethornis. guy coruscus is found on both the Pacific and Atlantic slopes in Central America, stretching from Costa Rica to Colombia and SE Peru (Stiles and Skutch 1989). It is replaced by P. superciliosus, the Long Tailed Hermit (now Long-billed Hermit; P. longirostris; Garrigues and Dean 2014), at lower elevations. On the Caribbean side, P. superciliosus replaces them starting at 400m while on the Pacific side, P. guy coruscus only extends down to 1000m. In Trinidad, P. guy guy exists without P. superciliosus and is therefore common from sea level to near mountain tops, at approximately 1000 m (Snow 1974).
The primary food source for P. guy is nectar from understory and edge plants such as Heliconia, Costus, and Razisea, in addition to Columnea found in the sub-canopy. They also feed on small spiders taken from webs (Stiles and Skutch 1989).
The lek, in which males of a species congregate and display in hopes of attracting a female, is a common behavior of P. guy. Leks tend to occur in dense primary forest near a source of water such as a stream or swamp that can support Heliconia plants, which are an important source of both nectar and nest sites. Up to 20 males participate in the leks, each having territories nearby each other, usually with flexible boundaries (Snow 1974, Stiles and Skutch 1989). Territories are about 190m2, with center points between 10 and 19 meters apart. Males remain in their territories throughout the breeding season, which was identified as December to June for an observed lek in the Arima Valley of Trinidad (Snow 1974). Studies in Monteverde, Costa Rica, have indicated that breeding time is similar (Snow 1977). Males then leave the lekking area to molt. Young males join the lek later in the season, when older males molt and vacate their territories (Snow 1974).
While in their territories, males sing from one of a few perches. Singing is accompanied by tail bobbing, and usually occurs in the corner of the territory closest to the nearest female (Snow 1974). The song is learned, and may vary slightly between both populations and individual leks (Snow 1974, Snow 1977). For example, the normal song used in displaying by birds in Trinidad (P. guy guy) was described by Snow (1974) as a watch, however some males learn a two-syllable song described as a watch-ee. The call of the Central American P. guy coruscus is described as a monosyllabic chew, less harsh than the song of P. guy guy (Snow 1977). Stiles and Skutch (1989) described the call as a chrrk or a twurrp. It was found that males sang far more frequently when others were also signing, and that males in the more central areas of the lek sang more often than those on the periphery (Duffy 1980, MacDougall-Shackleton and Harbison 1998). Aside from the lekking call, P. guy also exhibits a flight call and a chase call. The flight call is used most often by females flying close to their nests, but males have been found to use it during the molting season. It is described as a repeated titch. The chase call is only used at the lek, most likely by males either confronting females or other males on their territory (Snow 1974). It is described as ‘a high pitched rapid chit’ or chitch (Snow 1974, Duffy 1980).
The main lekking display used by the males is the tock-display, in which a male darts from side to side (usually about 1-2 feet apart), opening its bright red gape at each change of direction. The gape display is accompanied by a tock sound and is sometimes used for establishment of territory, but is usually a pre-mating ritual. Speed of the display varies between individuals, and young males tend to display more frequently than older males (Snow 1974). Another important aspect of the mating ritual was the gape display, used for both aggressive and non-aggressive purposes (Snow 1974). The non-aggressive gape display is used when another bird comes into the territory from above, and consists of a tail fanning followed by the upwards display of the gape (Snow 1974, Duffy 1980). The aggressive version is used when other birds, especially other males, approach from in front of the male. In this display, the male shows its gape in a forward direction. One difference in lek behaviors between P. guy guy and P. guy coruscus is that P. guy guy made a tsee noise while displaying the upward non-aggressive gape, whereas P. guy coruscus was silent (Snow 1974, Snow 1977).
Females enter the lekking area from above, landing higher up than males. She hovers down closer to the males, at which point they stop singing and begin their gape-displays. Once the female has chosen a male, they exchange tock-displays, then possibly copulate. After copulation, the male chases the female out of his territory. Males may also engage in false mating, in which they perform tock-displays and hover over a dead leaf (Snow 1974).
P. guy has been shown to enter torpor at night, during which both body temperature and metabolism decrease. In a laboratory setting, torpor was observed to last for roughly 8 hours, with the lowest metabolic rate occurring three hours after darkness commenced. Torpor was entered during trials at 15, 20, 25, 28, and 35 degrees Celsius, suggesting that torpor entry was reliant on light instead of temperature. Metabolic rate begins to increase slowly three hours before daylight, then more rapidly in the last hour (Schuchmann and Prinzinger 1988).
The nesting season for P. guy populations in Trinidad is typically between January and May, coinciding with the peak flowering season of two of their preferred sources of nectar: Heliconia bihai and Pachystachys coccinea (Snow 1974). In Costa Rica, nesting season has been observed to be February through September (Stiles and Skutch 1989). Nests are typically cone-shaped and attached to a leaf by spider webs. Common plants for nesting include Cyclanthus, Heliconia, or Monstera, all of which could provide protection from rain. Nests are pale brown and comprised of a variety of materials (Snow 1974). The structural element is made of pieces of bark and twigs, while the inside of the cup is made from softer materials such as seed plumes from trees or tree-fern scales. Spider webs are used not only for attachment to the leaf, but also to secure the rest of the structure (Snow 1974, Stiles and Skutch 1989).
Once the nest is completed, the female lays 2 eggs. Incubation lasts for 17-18 days, during which the female spends nearly all of her time on the nest. When born, the hatchlings are covered in down that matches the color of the nest. Feathers appear on chicks between the 9th and 16th days. Chicks recognize their mother’s flight call and begin begging when they hear her approaching the nest. The mother feeds the chicks approximately once an hour, leaving them unattended between feedings. One study found nesting success to be 26%, and snakes to be the most probable nest predators (Snow 1974).
The green hermit (Phaethornis guy) is a large hummingbird that is a resident breeder from southern Central America (Costa Rica and Panama) south to northern South America (north-eastern Venezuela and Trinidad, and the northern Andes of eastern Peru)
It is 13.5 cm (5.3 in) long and weighs 6.3 g (0.22 oz). The male is mainly dark green with a blue-green rump. It has a dark mask through the eye, with buff stripes above and below this, and down the centre of the throat. The central feathers of the tapered tail are—for large hermit—relatively short and white-tipped, and are wiggled in display at the communal leks. The reddish bill is long and decurved. The female is sooty gray (rather than green) below, with an even longer bill and a much longer tail. The call of this species is a loud zurk, and the males' lekking "song" is a repeated swark.
The nominate subspecies Phaethornis guy guy is found in Venezuela and Trinidad. The western P. g. apicalis of the American cordillera is slightly smaller and the sexes more similar.
This hermit inhabits forest undergrowth, usually near water, and prefers hilly areas. It seems to favor primary rainforest and wet premontane forest, and though it tolerates some amount of habitat destruction (e.g. subsistence farmland) it will try to avoid secondary forest as long as better habitat is available. In the Colombian Cordillera Oriental, it has been recorded at altitudes from 650–1,750 m (2,130–5,740 ft) ASL. Habitat there usually has a canopy height of around 25 m (82 ft) and is dominated by trees such as Elaeagia (Rubiaceae) or palms;[3] there is usually plentiful undergrowth and/or epiphytes and hemiepiphytes (e.g. Clusiaceae).[4]
The food of this species is nectar, taken from a wide variety of flowers, and some small insects; it prefers flowers 30–50 mm long by 2–7 mm wide, though it will occasionally visit flowers up to 75 mm long and 20 mm wide or as short as 15 mm. At Monteverde (Costa Rica), preferred foodplants include yellow jacobinia (Justicia umbrosa) and Razisea spicata (Acanthaceae), Pitcairnia brittoniana (Bromeliaceae), spiral ginger (Costus barbatus, Costaceae), Drymonia conchocalyx and D. rubra (Gesneriaceae), Heliconia tortuosa (Heliconiaceae), and Malvaviscus palmanus (Malvaceae). Less commonly visited flowers were mostly Gesneriaceae,[5] Heliconiaceae (such as Heliconia bihai),[6] Acanthaceae (such as Pachystachys coccinea)[6] and Zingiberales,[7] but also certain Bromeliaceae[8] (such as Tillandsia fasciculata)[6] Campanulaceae[9] (such as Centropogon surinamensis),[6] Ericaceae[10] and Rubiaceae.[11][12]
As noted above, males assemble at leks for courtship. In the Colombian Cordillera Oriental, active leks were observed between September and November, but neither in August nor in December, indicating a distinct breeding season.[4] The green hermit lays one egg in a conical nest suspended under a large leaf, usually over water. Incubation is 17–18 days, and fledging another 21 to 23 days.
The green hermit (Phaethornis guy) is a large hummingbird that is a resident breeder from southern Central America (Costa Rica and Panama) south to northern South America (north-eastern Venezuela and Trinidad, and the northern Andes of eastern Peru)
