Habitat and food preferences in a guild of insectivorous mammals in the Western Pyrenees

The use of trophic and spatial resources in a guild composed of five species of insectivorous mammals (Galemys pyrenaicus, Talpa europaea, Neomys fodiens, Sorex coronatus, and Sorex minutus) was studied. The characteristics of the macrohabitat were studied based on data from trap lines. Those pertaining to the microhabitat were examined through a study of the sites where each animal was caught. The diet was studied by analysis of the digestive tract as well as the availability of resources in various microhabitats. The results show a high level of segregation in the use of trophic resources. The microhabitat used on the ground surface has a low level of segregation among the shrews. A comparison of the diet of each species with the results from the invertebrate sampling carried out in different microhabitats (water, subsoil, humus, ground surface) shows that there is a relation between the food consumed and its availability in the microhabitats utilised by each species. This study suggests that the coexistence among the insectivorous species studied may be ex­plained by the use of the microhabitat and diet segregation. The differences in diet would be a consequence of the use of different microhabitats. Servicio de Conservacion de la Biodiversidad, Gobierno de Navarra, C.I Alhóndiga 1, 31002 Pamplona, Spain (EC); Departament de Biologia Animal, Facultat de Biologia, Universität de Barcelona, Avgda. Diagonal 645, 08028 Barcelona, Spain (JG)