Nest mortality and the viability of lark populations

Full article

Published:

Volume 43(1), June 1996. Pages 57-68.

Language:

Spanish

Original title:

Mortalidad en nido y viabilidad poblacional en aláudidos

Keywords:

Calandrella rufescens, Galerida theklae, nest mortality, population, productivity.

Abstract:

Levels of nest mortality in Calandrella rufescens and Galerida theklae are described for two localities in the SE of the Iberian Peninsula, "Las Amoladeras" Bird Reserve and a control area, from 1992 to 1994. Mortality rates were very high at both sites (32-98% of nests failed depending on locality, species and year). The predation risk in the Reserve was higher than in the control area, and than that recorded before the zone became a Reserve. The main cause of nest failure was predation, which involved between 48-90% and 95-100% of losses of eggs and nestlings, respectively. According to a model specifically designed to estimate productivity, the latter is insufficient to permit lark population stability in the Reserve, but it would be possible in the control area.