Hailstorms as cause of mass mortality of Swainson's hawks in their wintering grounds.

SARASOLA, J.H.; NEGRO, J.J.; SALVADOR, V.; MACEDA, J.J.

JOURNAL OF WILDLIFE DISEASES

WILDLIFE DISEASE ASSOC, INC

Año: 2005 vol. 41 p. 643 - 646

0090-3558

We describe a mass mortality episode of wintering Swainson´s hawks (SH, Buteo swainsoni) in central Argentina on November 2003. One hundred and thirteen Swainson´s hawks were found dead as a consequence of a single hailstorm. In addition 14 hawks with severe injuries were recovered alive, but only 10 of these survived one week later. Another 45 dead birds of 11 species were collected in the area. Interviews with local landowners conducted in other areas of the wintering grounds for Swainson´s hawk provided further evidences of past mortality incidents and hailstorms involving Swainson´s hawks. This suggests that this kind of mortality factor could be frequent in the Argentine Pampas. This is another cause of mass mortality of Swainson´s hawks wintering in agricultural areas of Argentina, that should be added to massive poisoning events suffered by this species during the last decade.