Do the exotic squirrel affect native birds in exotic forest of the Pampas?

MESSETTA, ML; ACOSTA, D; ALMADA CHAVEZ, S; MIRANDA, L; MUFATO, N; MILESI, F; GUICHÓN, ML

Mendoza, Argentina

Congreso; International Mammalogical Congress; 2009

Biodiversity Research Group (GIB), Institute for Aridlands Research (IADIZA), Center for Science & Technology Mendoza (CCT), National Council of Science and Technology (CONICET), International Federation of Mammalogists(IFM) and SAREM

Biological invasions are a major threat to native species. The red bellied tree squirrel Callosciurus erythraeus was introduced in Luján, Argentina, in 1970 and it spread rapidly. Local inhabitants claim a negative effect on native birds; squirrels can affect birds through nest predation, interference and competition for food and nest sites. We aimed to compare bird richness and abundance in forested areas with and without squirrels. We selected 28 sites, 14 inside and 14 outside the distribution area (700 km2 in 2004) of the main population of these squirrels; half of these were paired sites of similar structure and tree composition. We did 4?5 point counts in each site during spring-summer 2008-09, recording all bird individuals identifiable to species level that were seen/heard during 8 min,