Guira Cuckoo Guira guira Scientific name definitions

The Guira Cuckoo is perhaps the most common cuckoo over a diversity of drier habitats from the mouth of the Amazon south to central Argentina. The Guira Cuckoo is highly social and is generally seen in flocks of 6-8 birds which can accrue to over 20 individuals at times, especially after breeding. The species also breeds communally, with several females laying up to 20 eggs in a single nest. Within the nest, there is much competition between parents and only a quarter of the eggs survive to fledging, the remainder are destroyed or buried or killed as hatchlings by competing adults.

36–42 cm (including tail of c. 20 cm); male 128·6–168·2 g, female 103–168·6 g (1 Pagano, L. G., and S. A. Salvador (2017). Datos de pesos de aves Argentinas. Parte 4. Historia Natural 7:21–43. Close ). Adult shaggy-looking above, back and wings white-streaked brown, short orange-rufous crest, lower back white, tail blackish with broad whitish lateral area at base and at tip, central rectrices all dark except at base; whitish below , striped brown on throat and breast; bare facial skin yellow, iris yellow to orange, bill orange to yellow, feet bluish grey. Juvenile  with small white spot on tips of remiges, bill black and white, iris light grey.

E & S Brazil from extreme S Amapá and Pará S to Bolivia, Paraguay, N & E Argentina and Uruguay.

Second-growth scrub, drier tree and scrub savanna and scrub woodlands, pampas, pastures, coastal dunes. Groups huddle together on cold days and perch together in a tree at night. Roosts in trees. Sea-level to 1200+ m.

Resident. A vagrant (or escaped captive?) was found emaciated in Curaçao, though species unknown on the nearest mainland in Venezuela and Colombia.

Insects  , grasshoppers , cicadas, flying termites, spiders  , frogs , lizards  , snakes  ; eggs and nestlings of small birds; takes mice and rats in captivity. Gregarious, feeds on ground in flocks of up to 20 (mean group  size 6–8).

Noisy, plaintive whistles, “pio...pio...pio...pr...prr...prrr”, also guttural calls, a high gargled trill , and a “creep”.

In Brazil, some nest in dry months May–Aug but mainly in rains during Aug–Nov near Brasília, also Aug–Nov near Rio de Janeiro; Nov–Dec in Uruguay and Argentina. Group-living; flocks decrease in size in spring, when some groups split into pairs to breed. Sometimes lays in nests of other species, including anis, and may incubate with the anis. Nest a large open platform of sticks, high in thorny tree; often renovates old nest from previous season. Eggs  grey to turquoise with whitish chalky splotches and streaks raised in relief, variable within a nest; 28 mm × 37 mm, 25 g; a few nests have only one breeding pair, but in most groups several females lay in the same nest, average ten eggs  in a group nest (number of eggs greater in groups with more birds). Incubation 10–15 days; nestling pale-skinned, white hair-like down above, bill pale with black culmen ridge and mandibular rami, mouth-lining pale with raised papillae, black bar on tip of tongue; young leave nest by days 5–6 when disturbed, but typically fledge about day 15; 26% of eggs and 55% of hatchlings survive to fledging  .

Not globally threatened. Generally common. Has extended its range during the last 100 years, entering fields occupying deforested areas; common in Mato Grosso, SC Brazil, and also in E Bolivia; disappears with afforestation, and absent from forested parts of Amazonia. Is perhaps also in the process of colonizing SE Peru (Madre de Dios), although the species is not yet accepted onto the national list (3 Ugarte, M., Angulo, F., Lane, D.F., Lloyd, H., O’Neill, J., Plenge, M., Schulenberg, T., Valqui, T., Walker, B. and Zepilli, R. (2014). Reporte del Comité de Registros de Aves Peruanas (CRAP) del periodo 27313. Bol. UNOP. 9(3): 45–54. Close ). Has been bred in captivity, although the young may require hand-feeding.