Prey Selection 161 



the fecal pellets. If prey availability at sampling sites differed significantly from 

 prey taxa obtained in fecal samples, we assumed the bats were feeding selec- 

 tively. 



One-way analysis-of-variance (ANOVA) and the Bonferonni multiple 

 range test revealed that the diet of the bats remained constant over our sampling 

 period. Therefore, we compared the fecal samples of each species of bat to the 

 samples of insects collected throughout the summer. 



Since it is likely that bats feed in more than one vegetational communi- 

 ty type and the proportion of available prey may differ between vegetational 

 community types, we again followed Whitaker (1994) by prorating the time 

 spent foraging in different vegetational community types. We used telemetry 

 data to determine the time each bat species spent in each vegetational commu- 

 nity type and multiplied this by the proportion of insect taxa collected in that 

 vegetational community type. The prorated time spent in each vegetational com- 

 munity type was then summed to obtain the total proportion of insect taxa in the 

 bat's hypothetical foraging area. Only fecal samples from bats captured while 

 foraging in areas where insects were collected were used in this analysis. Dif- 

 ferences between expected and actual diet were determined using an ANOVA 

 (Sokal and Rohlf 1987). Significance was accepted at the p < 0.05 level. 



RESULTS AND DISCUSSION 



Fecal samples from 132 individual bats were examined: 99 N. hwner- 

 alis (Table 1), 24 L. seminolus, 4 P. subflavus, 3 E. fuscus, 2 L. intermedius 

 (Tables 2). Due to the large sample size of N. hwneralis, we were also able to 

 analyze this species in three groups: adult males, adult females, and juveniles. 

 Table 1 and 2 summarize fecal analysis data and prey availability comparisons. 

 Samples were collected from bats netted in all vegitational community types 

 except pine-oak, a community in which no bats were captured. Due to the size 

 of insect fragments found in fecal pellets, identification of only six major orders 

 was possible: Coleoptera, Hymenoptera, Lepidoptera, Hemiptera, Homoptera, 

 and Diptera. Other orders may have been present in lower quantities. Percent 

 volume and percent occurrence of insect orders consumed varied among species 

 (Tables 1 and 2). While previous studies suggest that small, insectivorous bats 

 are opportunistic feeders (Kunz 1974, Fenton and Morris 1976, Swift et al. 

 1985), each of the five species we studied demonstrated statistically significant 

 feeding selectivity for certain insect orders. 



Nycticeius humeralis 



Fecal samples from 99 evening bats were examined (Table 1). Six 

 orders of prey items were found. Coleoptera were present in 9 1 % of the fecal 

 samples followed by Hymenoptera (69%), Lepidoptera (48.5%), Hemiptera 

 (40.5%), Homoptera (7%), and Diptera (8%). No significant depar- 



