ARE EUROPEAN ROE DEER BROWSERS ?

A REVIEW OF VARIATIONS IN THE COMPOSITION OF THEIR DIETS

Hélène Tixier and Patrick DUNCAN*

Introduction

Roe deer (Capreolus capreolus) are the most abundant cervids in Europe : they occur between 35-70° N from the Atlantic to the Urals (Gill, 1990), and with over 5 million individuals they are five times as abundant as red deer (Cervus elaphus).

Their importance as a game species (Gill, 1990, Table 7.2), as a constraint on commercial forestry, and as a component of forest ecosystems means that roe deer populations are usually managed. This has led to a considerable amount of research on their biology, and particular attention has been paid to their diets and their digestive system, which has led to this species being described as the «Type example of a concentrate selector» (Hofmann, 1989).

However there is no review of the information available from the large number of field studies on the diets of roe deer. This is clearly a necessary step towards drawing general conclusions on the feeding of the species, whether to define its feeding strategy and niche, to evaluate overlap with other species such as red deer, or to understand the impact of roe deer on natural and modified forest ecosystems.

The data from studies of the diets of roe deer are dispersed in a large number of scientific papers and unpublished reports and theses ; as part of an interdisci¬ plinary study of the feeding and nutrition of roe deer, we review here the available information in order to :

— identify the main sources of variation in diets (e.g. season, habitat, altitude, latitude) ; and

— define the feeding niche of roe deer by determining the importance for them of the principal items typically eaten by small ungulates : woody browse, forbs, grass, seeds, fruit and fungi.

Methods

The different methods used for diet studies of roe deer

Stomach content analysis was the method most commonly used in the studies reviewed. It suffers from two principal problems, different passage rates of

Rev. Ecol. (Terre Vie), vol. 51, 1996.

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