Ecological correlates of roe deer fawn survival in a sub-Mediterranean population

Abstract

We investigated the effect of body mass, spring and summer total rainfall, birth period, and local population density on the survival of 130 roe deer ( Capreolus capreolus (L., 1758)) fawns captured over seven fawning seasons (1997–2003) and radio-monitored daily. We modelled survival using the program MARK, incorporating biological questions into different models, following a priori hypotheses. The best model was selected using Akaike’s information criterion. The population was surveyed by counts and estimates were obtained using mark–resight methods. Weekly survival of roe deer fawns exhibits a pseudo-threshold time trend. Probability of survival is low (0.33 ± 0.0046) in summer, increases (0.79 ± 0.0021) in fall, and approaches the highest value typical of adult survival (0.90 ± 0.00091 and 0.96 ± 0.00021 by the end of March and May, respectively) during early spring following birth. The final model predicts that survival of roe deer fawns is positively affected by total precipitation in spring and body mass under a pseudo-threshold time variation pattern. In contrast with other studies, we did not detect any effect of population density on survival of fawns. This study contributes to the scarce knowledge about the performance of roe deer populations in Mediterranean ecosystems, providing evidence that climate variables and individual characteristics shape the vital rates of roe deer populations.