22-3-2017 TROGON LODGE, COSTA RICA - VOLCANO HUMMINGBIRD (Selasphorus flammula)

The Volcano Hummingbird, scientifically known as Selasphorus flammula, is a diminutive and vibrant member of the "bee hummingbirds" tribe Mellisugini. This species graces the highlands of Costa Rica and Panama with its presence and is notably featured on Costa Rica's 20 thousand colones bill.

Adult males of the Volcano Hummingbird are characterized by their bronze-green upperparts and striking mauve-purple gorget, with the rest of the underparts predominantly white. They possess rufous-edged black outer tail feathers, and their breast sides are tinged with buffy to pale cinnamon, speckled with green. Females, while also bronze-green above, have green central tail feathers with rufous bases, a black band near the end, and buffy to white tips. Their throats are whitish with dusky bronze speckles. Juveniles resemble adult females but have buffy fringes on their upperpart feathers.

The Volcano Hummingbird (Selasphorus flammula) is a very small hummingbird which breeds only in the mountains of Costa Rica and Chiriqui, Panama. This tiny endemic bird inhabits open brushy areas, paramo, and edges of elfin forest at altitudes from 1850 m to the highest peaks. It is only 7.5 cm long. The male weighs 2.5 g and the female 2.8 g. The black bill is short and straight. The adult male Volcano Hummingbird has bronze-green upperparts and rufous-edged black outer tail feathers. The throat is grey-purple in the Talamanca range, red in the Poas-Barva mountains and pink-purple in the Irazú-Turrialba area, the rest of the underparts being white. The female is similar, but her throat is white with dusky spots. Young birds resemble the female but have buff fringes to the upperpart plumage.

These hummingbirds inhabit semi-open to open high mountain slopes, thriving in environments such as páramo, second growth on landslide scars or ashfall areas, scrubby pastures, and the edges of elfin forest and taller forest.

The Volcano Hummingbird can be found across various high-elevation locations in Costa Rica and western Panama, with the nominate subspecies residing on Volcanoes Irazú and Turrialba in central Costa Rica.

During the breeding season, which spans from August or September to February, males establish small territories for courtship displays, while females construct nests of plant down and spider web adorned with moss and lichens. Post-breeding, some individuals may descend to lower elevations or migrate to adjacent mountains, allowing for subspecies intermingling.

While foraging, the Volcano Hummingbird emits soft chip notes. Males produce a thin whistled 'teeeeeuu' and a twittering 'scolding' call during confrontations with other males. The male's tail feathers create a series of broad-frequency pulses during their dive display.

The female Volcano Hummingbird crafts a cup nest on the outermost end of a twig, typically between 1 and 5 meters above the ground, occasionally on a rootly drooping from an earth bank. The specifics of the incubation period and fledging time remain a mystery.

The Volcano Hummingbird forages for nectar from a diverse array of small flowers and also consumes small arthropods, either caught on the wing or gleaned from foliage and spider webs.

The IUCN has classified the Volcano Hummingbird as Least Concern, with a fairly large range and a stable population estimated between 20,000 and 50,000 mature individuals. The species is found in protected areas and may even benefit from human activity, as it is more abundant in open areas than in forested ones.

Although this species may have a small range, it is not believed to approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.