Green Thorntail

How to find it

Look high and scan exposed treetop branches, where males perch on bare twigs. Flowering trees in clearings repay patience, because this tiny hummingbird comes and goes from them. Hummingbird feeders and gardens are reported to attract it, which gives a better chance of a close view. Around Turrialba, one was seen at a hedge of rabo de gato, a flowering shrub, and a female was photographed at a feeder. At the El Tapir hummingbird garden it is one of several hummingbirds that often show up, with Snowcap, Violet-headed Hummingbird and Rufous-tailed Hummingbird.

How to recognise it

The male is about 10 cm long. He is mostly green, with a white band across the rump and a long, wire-like, blackish tail. The tail is the first mark to look for.

The female is smaller and has a short tail. She has a bold white moustache, blackish underparts and a green chest band.

Both sexes are tiny, about 3 g, with a short straight bill. These descriptions cover the species across its whole range, not only Costa Rica.

Behaviour and diet

Males perch on high bare twigs and sometimes do a dive display. They also hold feeding territories, chasing off other males and large insects such as bumblebees and hawk moths.

It visits small flowers on epiphytes and shrubs, and takes small flies and wasps. It also picks insects from beneath the leaves of the canopy. Its flight is often compared to that of a bee. Much of its natural history is still unknown.

Where it lives

In Costa Rica the Green Thorntail lives on the Caribbean slope and is mostly found between about 700 and 1,400 m (2,300 to 4,600 ft). Range-wide, it may drop to lower elevations early in the wet season. A male has been seen at 550 m in Braulio Carrillo National Park, perched on a bare limb near the aerial tram entrance.

It mostly stays in the forest canopy, at forest edges and at flowering trees in clearings. Costa Rica is the northern end of its range.

When to see it

The breeding season is thought to run from November to April in Costa Rica.

Similar birds

A tiny hummingbird with a white rump band can only be a thorntail or a coquette. Costa Rica has three coquettes that could be confused with it: Black-crested, White-crested and Rufous-crested, the last a very rare visitor. The male thorntail has a very obvious long tail. The female shows a distinct white stripe on the cheek and none of the rufous colour of the coquettes.

Names and lore in Costa Rica

Costa Rican names for this bird are Colibrí Colicerda Verde and the shorter Colicerda Verde. Elsewhere it is called Rabudito Verde in Spain, Cola-de-lira Verde in Colombia and Coqueta de Cola Celeste.

Status and conservation

The official Costa Rican bird list classes it as a resident species (R), and the IUCN rates it Least Concern, though the population is believed to be decreasing and it is judged uncommon here.

Photography tips

Hummingbird feeders in lodge gardens are the best place to photograph it. Tour companies list it at garden feeders alongside Black-bellied Hummingbird and Coppery-headed Emerald. In the wild, scan exposed treetop branches for a perched male.