Black-billed Cuckoo

How to find it

Do not wait for a call, because migrants are silent here. Plan your looking around the spring and autumn passage windows, and spend time in the lowlands at scrubby areas and forest edge. Scan leafy branches and bushes slowly, since a cuckoo hunting caterpillars may sit still for long periods. Check each bird for the red eye ring, the black bill and the thin white tail tips. One Costa Rica writer thinks the species is probably present in fall, perhaps in shade trees, and that too few people are out looking for it. His own sightings were single birds in towns, being chased by grackles, so settlements are worth a glance too.

How to recognise it

Start with the red ring of skin around the eye. It is the detail that catches the eye first.

Then check the rest of the bird, using marks described for the species across its range:

Upperparts: grayish brown, or brownish olive in one description.

Underparts: dull white.

Bill: black, with a blue-gray base on the lower half.

Legs: blue-gray, or gray.

Tail: gray, with only thin white tips.

Eye: dark brown iris.

Size: about 30 cm long.

The tail is the clearest way to separate it from the Yellow-billed Cuckoo, whose tail shows bold white spots.

What it sounds like

Recording: elacroix-carignan, CC0 1.0, source, read 4 Nov 2026.

Behaviour and diet

This cuckoo is shy and usually alone. It moves slowly and deliberately through dense foliage and often sits still for long periods, which is a large part of why it is so easy to miss. It forages in shrubs or trees by day.

It eats mainly caterpillars, including hairy ones, and katydids. It specializes in hairy caterpillars that many birds avoid, and it can line its stomach with the spines and shed them later.

It migrates at night, and on migration it may travel in mixed flocks with other species.

Where it lives

In Costa Rica it is seen only as a passing migrant, mainly in the Caribbean and Pacific lowlands and sometimes in the eastern Central Valley. On migration and in winter the species prefers scrubby areas and forest edge. Its winter home lies in northwestern South America, so Costa Rica is a stopover rather than a destination.

One record comes from a highland site, the upper Río Tiribí Protected Zone in Cartago, well above the usual lowland records. Passing migrants can also turn up at ordinary home gardens, where one Costa Rica birder counted it among new yard birds.

When to see it

In spring, from April to early May, it is a very uncommon to very rare migrant in the Caribbean and Pacific lowlands and occasional in the eastern Central Valley. In autumn, from late September to early November, it is very uncommon to very rare in the lowlands and eastern Central Valley.

Similar birds

The Yellow-billed Cuckoo is the likely confusion in Costa Rica. It is also a migrant, but it is more often seen. It has a yellow lower bill (except in young birds), a grayish eye ring and larger pale tips on the tail feathers, with bold white tail spots. The Black-billed has red eye skin and a gray tail with only thin white tips.

Names and lore in Costa Rica

The official Costa Rican name is Cuclillo Piquinegro, and the national list gives no local nicknames for it. Cuclillo de ojo colorado and Pájaro bobo pico negro are also used in Spanish, but they are regional or general names, not shown to be specific to Costa Rica.

Status and conservation

The official Costa Rican bird list (2025-2026 edition) classes the Black-billed Cuckoo as a migrant, and it is less common here than the Yellow-billed Cuckoo.

Photography tips

Migrant Black-billed Cuckoos are hard to find because they are silent, so focused watching plus luck is the plan. Look for single birds in shade trees, scrub and even towns, and give any still cuckoo time, since it may stay put for long periods.