Weeds as a predominant food source: a review of the diet of common hamsters Cricetus cricetus in farmlands and urban habitats
Résumé
1. The common hamster Cricetus cricetus was long considered to be a pest
species for crops, but its populations are now dramatically declining. The
conservation of this species can only be achieved via an up-to-date knowledge
of its ecology. However, its diet composition has never been exhaustively
reviewed and the last peer-reviewed publication on its feeding ecology in
farmlands dates back to 1974.
2. This review of the literature aims to establish a list of plant and animal taxa
consumed by common hamsters, providing knowledge to be applied to the
conservation of hamsters and to identify the main avenues of future
research.
3. Hamsters consume four main categories of food: crops, weeds, trees/shrubs
and animals, including mammals, birds, herptiles and invertebrates. Vegetable
foods are more diverse (114 taxa) than animal foods (11 taxa). Hamsters
mainly consume animals and green parts of plants (flowers and leaves) in
spring and summer, and store energy-rich and non-perishable foods for
winter.
4. Weeds are the most diverse food category (61 taxa), followed by crops (31
taxa). However, diet shifts from crop products towards tree products in urban
habitats, probably in response to a marked difference in availability.
5. We conclude that hamsters have an opportunist diet that shows a high degree
of plasticity, and that weeds make up an important part of their food supply.
However, the studies published to date have considered diet composition
without taking food availability into account, and therefore lack information
on whether the hamsters select the foods consumed or simply consume them
because other foods are not readily available. Research on food availability
and selection is therefore needed. Moreover, we argue that there is a need
for recent data on the feeding ecology of the hamster in relation to fitness.
This would provide a crucial tool for the implementation of adapted conservation
measures for this declining species of rodent.