The streak-throated hermit hummingbird (Phaethornis striigularis) is a small hummingbird found in tropical South America. With an average body length of 11-12 cm and weight of 5-7 grams, it is a relatively petite species of hermit hummingbird. Its plumage is mostly green above and white below, with the adult males having a bold streak of iridescent blue feathers along the throat. The females lack this striking blue throat patch. The streak-throated hermit gets its name from this distinctive feature.
Range and Habitat
The streak-throated hermit has a range across the Amazon Basin in South America. Its habitat consists of tropical rainforests, forest edges, second growth woodlands, plantations, and gardens. It ranges across parts of Colombia, Venezuela, Ecuador, Peru, Bolivia, and Brazil. Within this range, it occupies both lowland and foothill tropical forests up to elevations of 1200 m. It prefers habitats with a dense understory and plenty of flowering plants.
Physical Description
The streak-throated hermit hummingbird averages 11-12 cm in length and 5-7 grams in weight. The adult male has vibrant green upperparts from its back to the top of its head. The undertail coverts are rufous colored. The throat is brilliant turquoise to cobalt blue, with each feather having a thin black border that creates a streaked look (giving the bird its common name). The breast and belly are greyish white in color. The bill of the streak-throated hermit is mostly black, long and decurved. The eyes are brown. The legs and feet are flesh-colored.
The female streak-throated hermit lacks the bold blue throat feathers. It has more drab white underparts overall, with some buffy streaking along the throat. The juvenile birds resemble the adult female.
Diet
Like all hummingbirds, the streak-throated hermit feeds on nectar from flowering plants. It uses its specialized long bill to drink the nectar while hovering in front of flowers. This species prefers flowers with a good amount of nectar that are located in the dark forest understory. Some favorite food plants include heliconias, gingers, and bromeliads. The hermit will aggressively defend flower clumps and feeding territories from other hummingbirds.
In addition to nectar, the streak-throated hermit supplements its diet by catching small insects and spiders. It hawks flying insects from a perch or sometimes gleans them from foliage. Consumption of insects provides this hummingbird with essential amino acids that are not obtained from nectar alone.
Behavior
The streak-throated hermit hummingbird is somewhat solitary and territorial. Males establish feeding territories, typically centered around particularly productive nectar plants. They chase away other hummingbirds that try to feed within their territory, even additional streak-throated hermits. Females, on the other hand, do not hold fixed territories. They may visit and exploit flowers across a broader area dominated by multiple male territories.
In the non-breeding season, the streak-throated hermit joins mixed flocks with other hummingbird species. This improves foraging efficiency while retaining access to preferred flower resources.
Though fairly aggressive at feeders and flowers, these hermits are generally shy and quiet otherwise. They utilize low, understory perches quite frequently, sitting motionless for prolonged periods. Their green plumage renders them very cryptic when motionless.
Reproduction
The breeding season for streak-throated hermits varies across their South American range. In Brazil and Bolivia, breeding occurs November through May. Further north in Colombia and Venezuela, the season lasts from March to August. The rest of the year these birds are not raising young.
As solitary nesters, the males do not participate much in parental care. The females build a small cup nest on a low horizontal branch or tree fern. Lichen and other debris camouflages the exterior. The female lays 2 tiny white eggs and incubates them alone for 16-19 days. She broods and feeds the hatchlings until they fledge in about 20-26 days. The young streak-throated hermits reach sexual maturity in their first year. Pairs may reunite for subsequent breeding attempts.
Vocalizations
The vocal repertoire of the streak-throated hermit includes various buzzing and whistling notes. Both sexes produce foraging and aggression calls while defending floral resources. These include buzzy chattering notes mixed with sharp seet and cheep sounds. Their wings produce a humming, whistling noise in flight. Outside of the breeding season, these hermits are relatively quiet and unobtrusive.
Threats and Conservation Status
Widespread throughout its range, the streak-throated hermit hummingbird has a conservation status of Least Concern according to the IUCN Red List. Habitat loss from deforestation poses the biggest threat across parts of its range. The species adapts readily to gardens and forest fragments in some developed areas. Providing nectar feeders and preserving native flowering plants can assist local populations. Overall, this hermit remains common across most of its South American extent. Ongoing monitoring helps conserve this dashing little hummingbird into the future.
In summary, the streak-throated hermit hummingbird is a striking small hummingbird decorated by iridescent blue throat streaks in the males. A denizen of the South American rainforests, it occupies a variety of forest and edge habitats. Territorial behavior, nectar-robbing foraging, and cryptic sitting posture allow this hermit to thrive in its tropical ecosystem. Though habitat loss affects some populations, overall the streak-throated hermit remains a common and resilient hummingbird species. With a fascinating appearance and behaviors, it provides an excellent representative of South America’s diverse hummingbird fauna.