Foods of Bats (Family Vespertilionidae) at Five Locations in New Hampshire and Massachusetts

Résumé

Diet and feeding relations of six species of bats at five locations in New Hampshire and Massachusetts were studied to improve understanding of foraging niche differentiation. Fecal samples were collected from 100 Big Brown Bats (Eptesicus fuscus), 154 Little Brown Myotis (Myotis lucifugus), 49 Northern Myotis (M. septentrionalis), 54 Eastern Small-footed Myotis (M. leibii), 9 Eastern Red Bats (Lasiurus borealis), and 1 Hoary Bat (L. cinereus) netted during non-hibernation periods from 2004 to 2008 at four locations in southern New Hampshire and one in north-central Massachusetts. Beetles (Order Coleoptera) were the major food of E. fuscus (mean percentage volume = 81.6%, 97% occurrence) followed by moths (Order Lepidoptera), with scarabaeid and carabid beetles the most abundant consumed families by volume and frequency. Moths were the most important item by volume and frequency preyed on by the remaining species (M. lucifugus, mean percentage volume 30.7%, 82% occurrence; M. septentrionalis, mean percentage volume 42.7%, 82% occurrence; M. leibii, mean percentage volume 49.4%, 81% occurrence; L. borealis, mean percentage volume 62.8%, 100% occurrence; L. cinereus, mean percentage volume 82%, 100% occurrence). Little Brown Myotis consumed the largest variety of prey (40); Northern Myotis consumed the highest volume of spiders (8.1%). Community similarity index values indicated diets of the three species of Myotis were more similar to each other (similarity = 0.71) than to those of non-Myotis. The diet of E. fuscus was more similar to that of the Myotis cluster (0.58) than to either species of Lasiurus. Results suggest that, despite faunal differences between the U.S. Northeast and other parts of North America, foraging relationships among guild members follows a similar pattern.