Swallow-tailed Hummingbird

Appearance

With a total length of 15–17 cm, nearly half of which is made up by the tail, and weighing up to 9 g, this is a relatively large hummingbird. Indeed, in much of its range it is the largest species of typical hummingbird. Its wings are also nearly 8 cm long – quite much for its size by hummingbird standards –, though its bill is only of mediocre length, with c.21 mm not longer in absolute terms than that of many smaller relatives.

Its plumage is brilliant iridescent green, with a blue head, upper chest, tail and vent. The tiny white spot behind the eye, common among hummingbirds, is often not visible in this species, but the white ankle tufts, also common among the Trochilinae, are well-developed. The remiges are blackish-brown. It has a slightly decurved medium-long black bill. The sexes are very similar, but females are about one-fourth smaller and slightly duller than males on average. Immature birds appear like females, but their heads are particularly dull and brownish-tinged.

Its voice includes relatively loud "psek" notes and weaker twitters. A "tik" call is given when excited or alarmed.

It is virtually unmistakable, although occasionally confused with the male violet-capped woodnymph. These have only a blue cap however, the remainder of their head is the same green as the belly.

Naming

Its common name and specific epithet both refer to the long, deeply forked, somewhat swallow-like tail.

Distribution

The majority of the range of the swallow-tailed hummingbird is in the Caatinga and Cerrado of Brazil, and adjacent parts of northern and eastern Bolivia, and far northern Paraguay. In the coastal regions, it occurs from French Guiana in north to Santa Catarina, Brazil, in south.

It generally avoids the rainforest found throughout most of the Amazon Basin, and only extends locally into this region along the southern and eastern edge, in the relatively open habitats along the lowermost sections of the Amazon River, including Marajó Island, and upstream to around the Tapajós River, and in isolated enclaves of woodland or savanna-like habitats within the Amazon in south-eastern Peru, southern Suriname, central Brazil, and northern Bolivia.

Status

Throughout the bulk of its range, it is among the commonest species of hummingbird, although it generally is uncommon in the outlying regions, particularly where it becomes more humid. In southern Brazil, it is apparently increasing and seems to have extended its range in recent decades. It is considered to be a Species of Least Concern by the IUCN. It was frequently exported for the cage bird trade up to 1970, but like other hummingbirds, it is nowadays on CITES Appendix II and trade is restricted. Also, hummingbirds are generally hard to keep in captivity, and though this species is generally rather hardy, it has been noted that abandoned young may die despite given optimal treatment when trying to hand-raise them.

Habitat

It occurs in virtually any semi-open habitat; even gardens and parks within major cities such as Rio de Janeiro and São Paulo. It avoids the interior of humid forest, but does occur in openings or along the edge; the swallow-tailed hummingbird is most common among savanna-like vegetation. It is generally a species of lowlands, but occurs locally up to 1,500 m. Not a true migrant, some populations move north or south a short distance in the dry winter months.

Reproduction

Across its range, it can be found to engage in some behavior related to reproduction almost year-round. In courtship, the male hovers in front of the sitting female and chases her through the air, and the two may beform a 'zig-zag flight' together; the former activity can be seen throughout the day except in the hottest hours around noon, while courtship chases are most frequent at dusk.

Birds have been seen carrying nesting material between July and September and in December. The nest is a cup-shaped structure lined with soft plant fibres and clad on the outside with lichen and mosses, held together with spider webs. It is placed on a horizontal twig in smallish trees, e.g. "Cochlospermum", typically below 3 m, but occasionally as high as 15 m above the ground. The clutch consist of two white eggs and like in other hummingbirds. Only the female takes care of the eggs and young.

The chicks hatch after 15–16 days; they are initially hairless, save for some grey down on the back, and have dark skin. They start to grow feathers 5 days or so after hatching, starting with the remiges; the rectrices begin to emerge about 3 days later. The young are fed 1-2 times per hour on average, and the female spends about half of the day brooding and feeding her offspring, and the other half flying around and feeding. The young fledge after 22–24 days but still return to the nest to sleep and be brooded for some more days; they are independent some 2–3 weeks after fledging. Two broods may be raised subsequently, sometimes reusing the nest; due to the prolonged breeding season, three broods might be raised per year in theory, but this does not seem to happen. The species first breeds at 1–2 years of age.