Yellow Warbler

Galapagos Yellow Warbler (Setophaga petechia aureola)

Bright, energetic, and impossible to miss, the Galapagos Yellow Warbler adds a flash of colour to almost every landscape in the islands. A close relative of the mainland yellow warbler, this subspecies is believed to have colonised the archipelago less than 300,000 years ago, making it a relative newcomer to the Galapagos.

Identification

At around 12 centimetres long, the Galapagos Yellow Warbler is a small, slender bird with bright yellow underparts and an olive-yellow back. Males are distinguished by reddish streaks on the breast and a rusty cap during the breeding season. Females and juveniles are paler and less marked but share the same cheerful plumage and fine, pointed bill typical of warblers.

Behaviour and Diet

Active and inquisitive, yellow warblers flit constantly between branches or hop across the ground, searching for insects such as midges, caterpillars, and beetles. They catch flies in mid-air with flycatcher-like precision and sometimes forage near the intertidal zone, even entering buildings in pursuit of insects drawn to light.

Breeding

These monogamous birds nest during the warm, rainy months from December to April, when insect life is most abundant. The female builds a small, cup-shaped nest in a bush or tree, usually several metres above ground, and lays two to five buff-spotted eggs. Both parents feed the chicks, which hatch after about ten days. In strong El Niño years, when food is plentiful, pairs may breed multiple times in a single season.

Threats and Conservation

While still common across most islands, the Galapagos Yellow Warbler faces growing pressures from introduced species. The parasitic fly Philornis downsi reduces chick survival, the smooth-billed ani raids nests for eggs, and invasive mosquitoes have introduced avian malaria. Habitat loss and pesticide use near populated areas may also affect their insect prey.

Recent research has revealed another modern challenge. Noise pollution. Studies show that males living near roads on Santa Cruz and Floreana become more aggressive when their songs are masked by traffic noise, suggesting that even low levels of human disturbance can disrupt communication and breeding behaviour.

Where to See Them

The Galapagos Yellow Warbler is one of the most familiar land birds in the archipelago. It can be seen on nearly every island, from arid coastal scrub to highland forests, and is frequently flitting around the grounds of Galapagos Safari Camp, often singing to guests at breakfast. Its bright plumage, quick movements, and fearless curiosity make it one of the most endearing birds to encounter on a Galapagos Safari.