Diet and food selection by small mammals in an old-growth Atlantic forest of south-eastern Brazil

Author(s)

Pinotti, Bruno T. ^[1] ; Naxara, Laura ^[2] ; Pardini, Renata ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Biociencias, Dept Zool, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Biociencias, Dept Ecol, Sao Paulo - Brazil

• Document type: Journal article
• Source: Studies on Neotropical Fauna and Environment; v. 46, n. 1, p. 1-9, 2011.
• Web of Science Citations: 11

Abstract

Here we describe the stomach contents of nine small mammal species (seven rodents and two didelphid marsupials) co-occurring in an old-growth Atlantic forest area. For four terrestrial rodents, we also compared the importance of arthropods in the diet and the selection of arthropod groups by comparing consumption with availability. Small mammals and arthropods were sampled in a 36-ha grid containing 25 sampling stations spaced every 150 m, and 47 stomach contents were analysed. While plant matter was the predominant item in the stomach contents of two rodents (Oligoryzomys nigripes and Rhipidomys mastacalis), four species presented arthropods as the main food item (the rodents Brucepattersonius soricinus and Oxymycterus dasytrichus, and the marsupials Monodelphis n. sp. and Marmosops incanus) and three consumed more plant matter than arthropods, but had significant amounts of both items (the rodents Delomys sublineatus, Euryoryzomys russatus and Thaptomys nigrita). Our results suggest that differences in diet, coupled with differences in habit and microhabitat preferences, are important factors allowing resource partition among species of the diverse group of co-occurring terrestrial small mammals in Atlantic forest areas. Moreover, arthropods were not preyed opportunistically by any of the four terrestrial rodents, since consumption was not proportional to availability. Rather, selection or rejection of arthropod groups seems to be determined by aspects other than availability, such as nutritional value, easiness of capture and handling or palatability. (AU)

• FAPESP's process: 04/04959-1 - Responses of the small mammals from the mature areas of the Atlantic Rainforest to micro-scale variations to the habitat
• Grantee: Laura Regina Capelari Naxara
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 99/05123-4 - Biodiversity conservation in fragmented landscapes at the Atlantic Plateau of São Paulo (Brazil)
• Grantee: Jean Paul Walter Metzger
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants