Loss of a Citril Finch Serinus citrinella nest possibly as a result of ant predation

Ants have been reported as the direct or indirect cause for nest loss in a few bird species. Here we describe a possible instance affecting a Citril Finch Serinus citrinella nest in the Spanish Pre-Pyrenees. The nest was found on 18 may 2002, when building activity was detected. On 1 June, the female was observed with five eggs hatching, apparently normally. Two weeks later, or 14 June we tired to detect signs of parental behaviour, but did not manage to make contact with the birds at the nest site. During a nest control on 18 June we found it to contain only one egg, and to have been totally invaded by mountain ants Formica rufa. No dead chicks or broken eggs were found.

M. Forschler, j. Cabrera, t. Cabrera & a. Borras, Butlleti del Grup Catala d’Anellament, 2001; 18