Influence of temperature on the body mass of the Brambling

Full article

Published:

Volume 43(2), December 1996. Pages 139-144.

Language:

Spanish

Original title:

Influencia de la temperatura en las reservas energéticas del Pinzón Real

Keywords:

body mass, energy reserves, Fringilla montifringilla, temperature, Western Mediterranean, wintering.

Abstract:

In this study we examine the influence of several variables of temperature on the body mass (equivalent to energy reserves) of bramblings in the Western Mediterranean. Our aim is to compare the level of reserves in this area with the normal wintering areas in Europe and to ask if it is a population-specific trait or, alternatively, if there exists some degree of plasticity. We found a high negative correlation between the mean and minimum temperature of a few days preceding capture and body mass (best correlation for 8 days). Long-term variables of temperature (last 12 years) showed no significative correlations. These results indicate that birds may adjust their reserves adaptively in response to local environmental conditions. In our case the birds can limit their energy reserves and, with such a strategy, they may increase the probability of survival by avoiding the costs of carrying unnecessary fat.