The white-throated daggerbill hummingbird (Schistes geoffroyi) is a medium-sized hummingbird found in the northern regions of South America. With its striking black and white plumage and long, dagger-like bill, this species stands out among its relatives in the hummingbird family. In this article, we’ll explore the key characteristics, habitat, diet, behavior, breeding habits, and conservation status of this remarkable bird.
Physical Description
The most noticeable feature of the white-throated daggerbill is its exceptionally long, thin bill that measures around 5-6 cm in adult males. This bill is black, straight and sharply pointed, resembling a dagger or rapier. The bill accounts for around one third of the bird’s total body length. As well as being long, the bill is also wide at the base where it attaches to the bright white face.
The plumage is primarily green on the upperparts and white below. The back and upper tail coverts are a shiny golden green, while the wings are a darker blue-green. The underside of the tail is rufous-colored. As the name suggests, the throat is white, sharply demarcated from the blackish bib that covers the upper breast. The white throat extends backwards to form white “ear tufts”. Females are similar to males but have slightly shorter bills and duller plumage overall. Juveniles have buffy throats and breast bands.
This hummingbird reaches a length of around 11-13 cm and weighs 5-7 grams. The wingspan is approximately 6.5 cm. Overall the white-throated daggerbill has a sturdy, thickset appearance compared to other hummingbirds.
Range and Habitat
The white-throated daggerbill inhabits tropical montane forest and woodland areas of the Andes Mountains in Venezuela, Colombia, Ecuador, Peru and Bolivia. Its elevational range extends from around 1500-3000 m above sea level.
Within these mountain forests, the daggerbill shows a preference for forest edges, clearings, streamsides and areas with flowers. It is also found in agricultural lands and gardens near forests. The species occurs both in wet montane forest on the eastern slopes of the Andes and in drier temperate forests on the west.
Diet and Feeding
As with all hummingbirds, the white-throated daggerbill subsists primarily on nectar taken from flowering plants. Its long bill allows it to access nectar from tube-shaped flowers that have deep corollas. Some key nectar sources include plants from the families Bromeliaceae, Ericaceae, Gesneriaceae and Heliconiaceae.
The daggerbill sometimes also hawks small insects in flight, including flies and spiders. It uses its specialized tongue to capture the insects in mid-air. The proportion of insects in the diet increases during the breeding season when the high protein content is important for egg production and chick growth.
Unique Adaptations
The white-throated daggerbill has several physical and behavioral adaptations that allow it to thrive in the cool, high-altitude environments of the Andes Mountains. Its compact, thickset body shape reduces exposure to the elements and heat loss. The thick plumage layers also provide effective insulation.
A slower, more measured wing beat (around 12 beats per second compared to 50 for smaller hummingbirds) saves energy in the thin air of the high mountains. When temperatures drop at night, the daggerbill enters a state of torpor to conserve energy.
The long bill of this species is an obvious adaptation to feed from long-tubed Andean highland flowers. The bill’s slight upward bend allows it to probe into flowers more efficiently.
Behavior and Breeding
The white-throated daggerbill is solitary and territorial, with the males in particular aggressively defending their flower-rich territories. Their characteristic display involves hovering in front of an intruder while fanning the colorful tail and uttering sharp chip notes. Rival males may also lock bills and grapple in mid-air combat over territory disputes.
In the breeding season, male daggerbills perform elaborate courtship displays to attract females. These include flying in wide circles and vertical figure-eights while singing a high-pitched twittering song.
Nesting takes place from March to June across the range. The compact, cup-shaped nest is constructed using plant fibers and moss which the birds collect while perched. It is placed in a sheltered site such as on a tree branch, in a crevice or under an overhang.
The female lays just two small white eggs which she incubates alone for around 16-19 days. The chicks are fed by the female with some assistance from the male. They fledge after about 25-30 days in the nest.
Conservation Status
With its extensive range across multiple countries and ability to utilize both pristine and disturbed habitats, the white-throated daggerbill is currently evaluated as a species of Least Concern on the IUCN Red List of Threatened Species.
Local populations may face threats from habitat loss through deforestation, conversion of land for agriculture and mining activities. Climate change is also a potential threat for mountain species like the daggerbill. However, overall this unique hummingbird remains widespread and common throughout its Andean range. Strict enforcement of protected areas and sustainable land use practices will be key to safeguarding its montane forest habitats into the future.
Conclusion
The white-throated daggerbill hummingbird is one of several Andean endemics that has evolved to occupy a high-altitude niche. Its specialized adaptations, from the elongated bill to its compact heat-conserving body shape and hibernation abilities, allow it to survive in environments that are challenging for many other birds.
While superficially similar to the hermits, the white-throated daggerbill’s unique mix of anatomical and behavioral traits has led most experts to classify it as the sole member of its own genus Schistes. This species highlights the incredible diversity that exists among hummingbirds, a group that contains over 300 varied species occupying an amazing range of ecological niches across the Americas. With its distinctive appearance and weapon-like bill, the daggerbill is surely one of the most memorable and remarkable representatives of this fascinating avian family.