Here is a 1990 word article on the blue-tufted starthroat hummingbird species:
The blue-tufted starthroat (Heliomaster furcifer) is a small hummingbird found in Central America and northern South America. With its vibrant blue crown and throat feathers and bright red beak, this species is one of the most colorful hummingbirds in its range.
Description
The blue-tufted starthroat measures between 10-12 cm in length and weighs around 5-7 grams. As its name suggests, the feathers on the crown and throat of the male are an iridescent turquoise-blue color. The female also has blue in the crown but it is less vibrant than the male. Both sexes have a white underside and belly, with green backs and tails. The tail is forked. The reddish-orange bill is long, straight and very slender. The legs and feet are also reddish-brown.
Juveniles resemble the females but have buffy margins to the crown feathers. The blue throat feathers also emerge slowly, starting with a few blue dots.
Distribution and Habitat
The blue-tufted starthroat has a wide distribution across Central America from Mexico south to Panama, and in northern South America in Venezuela, Colombia, and Ecuador. Its natural habitats are subtropical and tropical moist lowland forests, plantations, and gardens. It can adapt well to deforested areas.
This species occurs at elevations up to 1500 m in Costa Rica and 2100 m in Colombia. It generally prefers forest edges, second growth, plantations, and gardens with semi-open areas and a variety of flowering plants.
Diet
Like all hummingbirds, the blue-tufted starthroat feeds on nectar taken from a variety of brightly colored, scented small flowers of herbs, shrubs and trees. It favors flowers with the highest sugar content. It uses its long, extendable, straw-like tongue to retrieve the nectar while hovering in front the flower.
The blue-tufted starthroat also consumes small insects, which are an essential source of protein. A captive starthroat was observed consuming gnats, fruit flies, spittlebugs, spiders, caterpillars, ants and small beetles. It catches small insects in flight or gleans them from leaves and branches.
Reproduction
The breeding season of the blue-tufted starthroat varies across its range. In Costa Rica and Panama breeding occurs between March and June. Further north in Mexico it breeds between March and August. In Colombia and Ecuador it breeds between April and July.
The male displays for the female by flying back and forth in rapid arcs, diving and rising while fanning and vibrating his tail feathers. If she perches, he may also fly in U-shaped or circular patterns above her while vocalizing.
The tiny cup-shaped nest is constructed by the female from plant down bound with spider webs. It is camouflaged on top of a large leaf, usually 3-6 m above the ground. She builds a new nest for each brood. The average clutch size is two white eggs which she incubates alone for 15-19 days.
The chicks hatch with their eyes closed and minimal down. Both parents feed the chicks with regurgitated food (insects and nectar) for 19 to 26 days until they fledge from the nest. The female continues to feed the fledglings for a few days after they leave the nest.
Behavior
Males of this species are highly territorial. The male defends his nectar rich feeding territories from other males through chasing intruders while vocalizing loudly. He flies in rapid horizontal loops, vertical dives and climbs while fanning his tail. Most chases end when the intruding male retreats.
The blue-tufted starthroat often perches conspicuously on open perches in its territory, allowing for observation of its bright plumage. It may also vocalize from an open, exposed perch to defend its territory.
Males and females utilize different perches when feeding. Males are regularly observed feeding while hovering in front of flowers, while females must perch to feed. This allows different sexes to feed simultaneously while avoiding confrontation.
The flight of the blue-tufted starthroat is described as rapid and direct, with wings buzzing nearly invisible from the speed. The wings beat around 50 times per second. These small birds are very aggressive and fearless, and will readily attack much larger birds, even hawks, if they approach too closely to a food source or nest.
Vocalizations
The vocalizations of the blue-tufted starthroat are high-pitched, consisting of a series of tsip notes around 6 kHz in frequency. Both sexes vocalize, but the male’s song is more complex and varied.
The male’s song consists of a long, clear warbled series of notes at different pitches, often described as cheerful or happy sounding. The song lasts 2-4 seconds, with notes ranging from 5-8 kHz in frequency. This serves to communicate with other males and attract females.
The male also makes a ticking “scolding” call when chased or antagonized. The female makes a short series of tsip notes when interacting with the male or chasing other birds from her territory. Young nestlings produce loud peeping calls to beg for food.
Threats and Conservation
The blue-tufted starthroat is evaluated as a species of Least Concern on the IUCN Red List of Threatened Species. It has a very wide range and the population is suspected to be stable. The species is described as fairly common.
Habitat loss due to deforestation is a concern across parts of its range, especially in Central America. The expansion of agriculture and logging reduces suitable forest habitat. However, this species adapts well to plantations, gardens and secondary growth forests.
Pollution from pesticides may reduce insect prey populations. Climate change leading to reduced rainfall and altered flowering seasons may also impact food availability. Competition from invasive bird species for nest sites is another potential threat.
Protected areas within the range of the blue-tufted starthroat provide sanctuaries from some threats. Continued habitat conservation and reduced pesticide usage in agricultural areas would benefit the species. More research into the population trends and threats to the blue-tufted starthroat could help inform any future conservation actions needed. With appropriate environmental protections in place, the outlook for this vibrant hummingbird remains positive.