The Black Metaltail (Metallura phoebe) is a small hummingbird found in the Andes mountains of South America. With its striking iridescent plumage and incredibly fast wingbeats, this species has captivated ornithologists and birdwatchers alike.
Introduction
The black metaltail is a medium-sized hummingbird, measuring around 9-10 cm in length. As its name suggests, the males have a distinctive black tail which shimmers with a metallic purplish-green in the sunlight. The rest of the plumage is a glittering green on the back and crown, with a white underside. The long bill is straight and black. Females are similar but lack the long central tail feathers and have white tipped tails instead.
This species has a very limited range, found only in the temperate forests and elfin woodlands of the Andes mountains in Peru, Bolivia and Chile between elevations of 1800-3600 m. It inhabits areas with plenty of flowering plants and tubular flowers which provide nectar, including shrubs, small trees and epiphytes. The inaccessible terrain and specific habitat requirements of the black metaltail have made it difficult to study and consequently many aspects of its biology remain poorly known.
Taxonomy and naming
The black metaltail is placed in the genus Metallura, one of the mountain gems which make up the subfamily Brilliantiniae. Its scientific name Metallura phoebe was given by the French ornithologist Jules Bourcier in 1847. The genus name Metallura refers to the metallic plumage while the species name phoebe comes from a character in Greek mythology who was associated with the moon.
There are two recognized subspecies of the black metaltail:
– M. p. phoebe is found in Peru and has slightly darker plumage.
– M. p. smaragdinicollis is found further south in Bolivia and Chile and has a greener throat patch.
Evolution and characteristics
Hummingbirds are found only in the Americas and like all hummingbird species, the black metaltail has evolved some remarkable anatomical adaptations to facilitate its specialist nectar-feeding lifestyle. These include a slender curved bill to probe flowers, a light skeleton, small size to enable aerobatic flight, and a rapid metabolism.
When feeding, the black metaltail beats its wings up to 70 times per second, enabling it to hover in place. This allows it to exploit food sources which other birds cannot. Its wings rotate in a full circle rather than just back and forth like other birds. All these adaptations enable the agile flight required to access nectar while hovering.
One unique feature of the black metaltail, shared with its close relatives the violet-throated metaltail and coppery metaltail, is the significantly elongated tail feathers of the male. This is thought to have evolved through sexual selection, providing a train of eye-catching ornate feathers which help attract females during mating displays.
Behavior and ecology
The black metaltail is solitary and territorial, with the male defending a territory and allowing a single female to occupy it and share the resources. Both sexes are highly aggressive towards intruders with males engaging in aerial chases and physical fights.
Food consists almost entirely of nectar which the black metaltail laps up with its specialized tongue. It also eats small insects which provide additional protein. favorite flower species include the red-hot-poker kniphofia and alstromeria flowers.
Reproduction takes place between October and January. The tiny cup-shaped nest is constructed by the female using plant fibers and spider webs, attached to a vertical rock face or tree trunk. She lays just two tiny white eggs which she incubates alone for around 16 days. The chicks are fed regurgitated food by the female and fledge after 22-26 days.
Status and conservation
The remote range and inaccessible habitat of the black metaltail has buffered it from some of the threats faced by other Andean hummingbirds. Its population is estimated to number between 10,000-100,000 individuals and it is currently classified as Least Concern on the IUCN Red List.
However, ongoing climate change and habitat alteration represent threats through drying forests and increasing competition for food sources. The impacts of tourists and recreational climbers disturbing nesting birds also need to be monitored.
Conservation priorities include retaining natural forest habitats and flowering plants within its elevational range. Some black metaltail populations may have benefitted from regeneration of woodland as marginal farmland at high altitudes is abandoned. Careful ecotourism which does not encroach on key breeding areas may also help raise awareness of this beautiful hummingbird.
Cultural importance
The black metaltail features prominently in the folklore of Andean cultures in Peru and Chile. One legend tells that the hummingbird was sent by spiritual elders to evaluate newlywed couples. If the couple lived in harmony, the hummingbird drank honey, but if they quarreled, it pecked holes in the walls of their house.
This story illustrates the perceived role of the black metaltail as an assessor of morality. More broadly, Andean cultures celebrated hummingbirds for their energy, vibrancy and industriousness. Imagery of hummingbirds was woven into fabrics and incorporated into jewellery as a symbol of vitality.
The black metaltail remains culturally significant today, featuring on Peruvian postage stamps and sought after by birdwatchers across the world who wish to see its dazzling plumage first-hand. Although small, this rare hummingbird has captivated human imaginations for generations. Maintaining its threatened Andean habitat will ensure this continues long into the future.