Factors influencing the distribution of exotic bird species in Comunidad Valenciana (Spain)

Full article

Published:

Volume 48(2), December 2001. Pages 149-160.

Language:

English

Keywords:

biological invasions, Comunidad Valenciana, discrimint analysis, distribution, Estrildidae, exotic species, habitat use, Psittacidae

Abstract:

By means of the information obtained from bird reports of the 1988-1998 period, we have studied the distribution for exotic bird species in Comunidad Valenciana. Forty-two bird species belonging to 9 avian families have been recorded, 69% of which belonged to Psittacidae, Estrildidae and Ploceidae. Only one species can be considered as exploited wildlife and the rest as pets. Twelve species have bred in the study area, Psittacidae being the family with more breeding species. We have detected an increase in both the number of species and the number of exotic birds in Comunidad Valenciana all through the study period. This increase does not seem to be a consequence of an uneven census effort, but results are far from conclusive due to the nature of the information sources used. Exotic birds were registered in 63 localities with a mean of 2.38 species and 4.54 records per locality. For the whole study area, a higher abundance was found for Psittacidae and Estrildidae species. Their number was not associated to any habitat type. However, while the more frequent records of Psittacidae species were found in both urban and wetland habitats, the higher records of Estrildidae were in wetland habitats. For these two families, we obtained a discriminant function to differentiate between localities with records and without them (86 and 92% of correct classifications, respectively). Human density was the most important variable used to differentiate among localities.