The European badger Meles meles: food specialist or generalist?



Although most authors characterize the badger Meles meles as an omnivore, the species is sometimes described as a food specialist and in particular as a specialist predator on earthworms Lumbricus terrestris. The validity of the‘food specialist’hypothesis is examined, using data from 11 quantitative studies of badger diet to test two predictions: 1) any one population of badgers relies to a disproportionate extent on a single type of food; and 2) consumption of the predominate food is independent of its availability. As regards the first prediction, when data on year-round consumption were corrected for seasonal variation in total intake, no study showed earthworms to comprise more than 50% of the diet and in three studies they accounted for no more than 5% of intake. In two studies, fruit comprised more than 50% of the diet and fruit and insects together accounted for 95–97% of total consumption. Compared across different studies, consumption of any one food, including earthworms, varied more or less continuously across a wide spectrum of values, providing no support for the idea that a given food can be characterized as being of either major or minor importance. With respect to the second prediction, there was no evidence that consumption of either earthworms or any other food was consistently invariant across seasons; and in any case, the idea that badger diet contains a constant proportion of any one food does not make functional sense. Taken together with information about the morphology of the digestive system and a priori arguments about the conditions in which food specialization is likely to be adaptive, studies of diet confirm that the badger is best viewed as a generalist or opportunist feeder.