Anthropogenic nesting sites allow urban breeding in burrowing parrots Cyanoliseus patagonus

TELLA, J.L.; CANALE, A.; CARRETE, M.; PETRACCI, PABLO F.; ZALBA, SERGIO M.

ARDEOLA

SOC ESPANOLA ORNITOLGIA

Año: 2014 vol. 61 p. 311 - 321

0570-7358

How birds adapt to urban life is a key question in evolutionary and conservation biology since urbanization is one of the major causes of habitat loss worldwide. Some species are able to deal with these anthropogenic changes, but a shortage of nesting sites may preclude them from breeding in cities. We conducted a baseline survey of the cliff-nesting burrowing parrot Cyanoliseus patagonus around Bahía Blanca (Argentina), estimating a minimum of 1,361 pairs breeding in 24 sites (colonies) in 2013. The species showed a facultative colonial behavior, colony size varying between 1 and 300 pairs. Most colonies (68%) and pairs (74%) occupied human-made substrates, mostly quarries but also water wells. Colony size was strongly correlated to the size of both natural and anthropogenic nesting substrates, suggesting an ideal free distribution of pairs according to the availability of nesting resources. Anthropogenic substrates surely allowed a population expansion in this rather flat landscape with shortage of cliffs and ravines, but also urban breeding by a large part (61 %) of the surveyed population. This currently constitutes one of the largest populations for burrowing parrots, a species previously abundant but progressively threatened by persecution and nest poaching for the international pet trade.