Monday, 1 May 2017

23-3-2017 SAN GERARDO DE DOTA, COSTA RICA - RUFOUS COLLARED SPARROW (Zonotrichia capensis)


The rufous-collared sparrow or Andean sparrow (Zonotrichia capensis ) is an American sparrow found in a wide range of habitats, often near humans, from the extreme south-east of Mexico to Tierra del Fuego, and the island of Hispaniola (split between the Dominican Republic and Haiti) in the Caribbean. It has diverse vocalizations, which have been intensely studied since the 1970s, particularly by Paul Handford and Stephen C. Lougheed (UWO), Fernando Nottebohm (Rockefeller University) and Pablo Luis Tubaro (UBA). Local names for this bird include the Portuguese tico-tico, the Spanish copetón ("tufted") in Colombia, as well as chingolo and chincol, and comemaíz "corn eater" in Costa Rica.


The rufous-collared sparrow is 13.5–15 cm (5+1⁄4–6 in) long and weighs 20–25 g (0.71–0.88 oz). The adult has a stubby grey bill, and a grey head with broad black stripes on the crown sides, and thinner stripes through the eye and below the cheeks. The nape and breast sides are rufous, and the upperparts are black-streaked buff-brown. There are two white wing bars. The throat is white, and the underparts are off-white, becoming brown on the flanks and with a black breast patch.

Young birds have a duller, indistinct head pattern, with brown stripes and a buff ground colour. They lack the rufous collar, and have streaked underparts.

There are between 25 and 29 subspecies. In general, the smaller forms occur in coastal mountains, intermediate birds in the Andes, and large, darker, forms breed on the tepuis. The largest of the tepui subspecies, Z. c. perezchincillae, has grey underparts, and the rufous collar extends as a black band of freckles across the breast. This form might be separable as a distinct species, or it might just be a particularly distinct population due to genetic bottleneck effects.


In the northern and western part of its range, this generally abundant bird is typically found at altitudes of 600–4,000 m (2,000–13,100 ft), but in the southern and eastern part it is commonly found down to near sea level. It can be seen in virtually any open or semi-open habitat, including cultivation, gardens, parks, grassland and scrubby second growth or cerrado. It copes well with urban and suburban environments, but is absent from the densely forested sections of the Amazon Basin.

It is also scarce on the Guiana Shield, occurring mainly on some tepuis and in the Pakaraima Mountains of Guyana.

The bird was described in 1992 as present on the island of Hispaniola and absence from the rest of the Caribbean, due to a similar theory to the one proposed for the Hispaniolan crossbill (Loxia megaplaga ), a sympatric bird. In that scenario, the bird's ancestors were present across the region during the much cooler climes of the last glacial period, but was left marooned in the highest Hispaniolan mountains (the highest in the Caribbean) once warming began. However, it is known to exist in Aruba and some other Caribbean islands.

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