Bird
Barn Swallow
Hirundo rustica
Photo: Imran Shah · Gilgit-Baltistan, Pakistan (CC BY-SA 2.0)
The Barn Swallow is the most widely distributed and abundant swallow in the world, and one of the most recognisable migratory birds to visit Trinidad and Tobago. Distinguished by its deeply forked tail, metallic blue-black upperparts, and rusty-orange throat, it passes through T&T in large flocks twice a year as it travels between North American breeding grounds and South American wintering areas. It does not breed in T&T but can be seen in enormous numbers hawking insects over open fields, wetlands, and coastal areas during its peak passage windows. No other swallow in T&T combines the long outer tail streamers with the dark throat and metallic blue dorsal plumage of the adult Barn Swallow.
Identification
The Barn Swallow measures 17 to 21 cm including the long outer tail feathers (streamers) that can add several centimetres to overall length and are longer in males than females. The upperparts are glossy metallic blue-black; the forehead and throat are rich chestnut-orange; the underparts are pale buff to white. The tail is deeply forked with elongated outer streamers. Juveniles have shorter tails and paler, less saturated colour. In flight the streamers are visible even at a distance. The related Gray-breasted Martin is larger, lacks the chestnut throat, and has a shallower tail fork.
Migration
Barn Swallows breeding in North America undertake one of the longest migrations of any passerine, travelling 8,000 to 10,000 km from breeding grounds in Canada and the USA to wintering areas in South America. T&T lies on a principal migration corridor and the islands receive large numbers in both northbound (March to May) and southbound (August to November) movements. During peak migration, flocks of hundreds or thousands may gather over wetlands, particularly Caroni and Nariva, to roost communally in reedbeds. South American-breeding populations are also partially migratory and may add to wintering numbers in T&T.
Status in T&T
The Barn Swallow is a common seasonal visitor and passage migrant to both Trinidad and Tobago, with some birds present year-round. It is most numerous during migration periods when flocks can be spectacular at wetland roost sites. The species is fully protected under the Conservation of Wild Life Act and is not a game species. Globally the species faces emerging pressure from declines in aerial insect populations due to pesticide use and land-use change, a trend being monitored across its range.
Threats
- Aerial insect decline from pesticide use
- Wetland roost site drainage
- Nest disturbance in breeding areas (outside T&T)