High red deer density depresses body mass of roe deer fawns

Abstract

Many previous studies have pointed out that, when resources are limited, the potential for competition should be high among sympatric species that display overlaps in habitat and nutritional niches. However, reliable evidence of competition between red deer (Cervus elaphus) and roe deer (Capreolus capreolus) has not been yet reported for life history traits directly measuring performance such as body mass, reproduction, or survival. From long-term monitoring of deer populations in the reserve of La Petite Pierre (France), we measured the sex-specific responses of roe deer fawn body mass to changes in red deer density after accounting for possible confounding effects of date of shooting, climatic conditions, and roe deer density. As expected under the hypothesis of competition, red deer density in a given year had a marked negative influence on body mass of roe deer fawns born the same year and the following year. Fawn mass of roe deer males and females responded in similar ways to changes in red deer density. Our study provides the first evidence of a negative response of roe deer performance to high red deer density.

Habitat use by sympatric red and roe deer in a Mediterranean ecosystem

“…Although the nature of our evidence is only correlative, the strength of the negative association between roe and red deer is consistent with asymmetric competition (Ritchie et al, 2009). We observed a negative effect of red deer on roe deer distribution suggesting that roe deer are vulnerable to competition, which is consistent with previous studies (Danilkin, 1996;Latham et al, 1996;San José et al, 1997;Richard et al, 2010). Possible mechanisms of this alleged competition can be that the diet of red deer can also include plants eaten by roe deer (dietary overlap), suggesting a potential for exploitation competition (as has been showed in other areas, e.g., Latham et al, 1999).…”

“…This underlines that competition evidence is generally very difficult to obtain. However, Richard et al (2010) showed that the density of red deer had a negative effect on the body mass of roe deer fawns, suggesting that the interaction does have a unidirectional effect and that it is truly competition. However, most of these studies have been conducted in the temperate and continental parts of central and western Europe where densities are high and these species inhabit the core area of their distribution (Putman, 1996).…”

Impact of deer on temperate forest vegetation and woody debris as protection of forest regeneration against browsing

“…In the study area, the mean number of deer seen per km was 0. 54, 0.46, 0.55 and 0.55, respectively, in 2005, 2006, 2007 and 2008 for roe deer (mean = 0.53 ± 0.04; Richard et al, 2010Richard et al, ) and 0.69, 0.79, 0.87 and 0.86, respectively, in 2005Richard et al, , 2006Richard et al, , 2007Richard et al, and 2008 for red deer (mean = 0.80 ± 0.08; Garel et al, 2010).…”

“…Red and roe deer population densities have been maintained at relatively constant levels since 1984 (Garel et al, 2010;Richard et al, 2010) and in the past 10 years, an average of 40 red deer and 50 roe deer were harvested annually in la Petite-Pierre NHWR.…”

Reproductive potential of Roe Deer (Capreolus capreolus L.)

“…When resources are limited, there is more interspecies competition among sympatric species with overlapping ecological niches (ibid.). In France (Le Petite Pierre reserve), influences of interspecific competition between red deer and roe deer were studied (Richard et al, 2010). Red deer density in a given year had a marked negative influence on body mass of roe deer fawns.…”