The sooty-capped hermit (Phaethornis augusti) is a species of bird in the family Trochilidae, the hummingbirds. It is found in Brazil, Colombia, French Guiana, Guyana, Suriname, and Venezuela.[1] [2]
The sooty-capped hermit is closely related to the planalto hermit (P. pretrei) and may form a superspecies with it. Three subspecies of sooty-capped hermit are recognized, the nominate P. a. augusti, P. a. curiosus, and P. a incanescens. A fourth proposed subspecies P. a. vicarius, in the Colombian Andes, cannot be separated from the nominate.[3] [1] [4]
The sooty-capped hermit is about 14to long. Males weigh 4.5to and females 4to. They are mostly grayish brown above with a rufous rump and uppertail coverts. The next-to-inner tail feathers are longer than the others and all have white tips. Their underparts are gray. The face has a black "mask" with a white supercilium and gular stripe. The subspecies differ slightly in the intensity of the breast and uppertail covert colors and the size of the gular stripe.[4] What was once thought to be a separate species P. fumosus was determined to be a melanistic morph of the nominate sooty-capped hermit.[3]
Major taxonomic systems place the nominate subspecies of sooty-capped hermit in Venezuela's Coastal Range and eastern Andes and south on the eastern slope of Colombia's Eastern Andes; P. a. curiosus in the isolated Sierra Nevada de Santa Marta of northeastern Colombia; and P. a incanescens on the tepuis of southern Venezuela, western Guyana, and Brazil's Roraima state.[1] [5] [4] The South American Classification Committee (SACC) of the American Ornithological Society places the species in those four countries and also French Guiana and Suriname.[2]
The sooty-capped hermit is thought to be mostly sedentary, but some seasonal vertical movement has been documented.[4]
The sooty-capped hermit is a "trap-line" feeder like other hermit hummingbirds, visiting a circuit of flowering plants for nectar. It also consumes small arthropods, and has been observed catching them in buildings.[4]
Active nests of the sooty-capped hermit have been found in Venezuela between February and July and also between September and December. The nest is a cone-shaped cup; a typical one was made of moss and spider web with pieces of dried mud on the outer wall. It was suspended by a single stout cable of spider silk from a nail in a storehouse. Nests may be reused multiple times within a season. The clutch size is two eggs.[4]
The sooty-capped hermit's song is "a continuously repeated phrase consisting of 2–3 high notes followed by 2–3 somewhat lower ones, e.g. 'tsee-tsee-tsee-sew-sew....tsee-tsee-tsee-sew-sew...'." The male sings from a perch at a lek while wagging its tail. It also makes a "rather monotonous 'tseet'" call.[4]
The IUCN has assessed the sooty-capped hermit as being of Least Concern; though its population size is unknown it is believed to be stable. It is considered locally uncommon to common and seems "to adapt well to habitats modified by man".[4]