BULLETIN FLORIDA STATE MUSEUM


 Glossophaga too switches to fruit in the wet season, and other
 authors have found it also eating insects then (Fleming et al. 1972;
 Howell and Burch 1974). G. soricina is a rare bat on BCI and becomes
 even more rare in the wet season, indicating that it may undergo
 seasonal habitat shifts.
 The reproductive strategy of P. discolor appears to be similar to
 that of the frugivorous bats. Two birth pulses occur each year, the first
 of which is toward the end of the peak in flowering and at the begin-
 ning of the peak in fruiting. Females eat fruit and insects during both
 yearly periods of lactation. This diet may be richer in protein than a
 pollen and nectar diet.

 GLEANING CARNIVORES
 Nearly all gleaning carnivores depend on large insects as a primary
 food resource, though a wide range of vertebrates, invertebrates, and
 even fruits may supplement the diet. This large feeding guild has a
 more complex array of partitioning mechanisms than any other guild
 on BCI. Differences in body size, food types, foraging microhabitats,
 and possibly activity cycles operate to maintain the ecological
 distinctness among these species. Future investigators should con-
 sider potential competition between bats and other taxa that prey on
 large insects, such as nocturnal spiders, caprimulgid birds, and tree
 frogs.
 Gleaning carnivores prey upon food items moderately large in rela-
 tion to their own body weight just as fruit bats do. Also like fruit bats
 they carry prey items to feeding roosts whether the food be large in-
 sects (Wilson 1971b) or birds (Vehrencamp et al. 1977). Because of the
 high protein content of their diet these bats possibly eat a smaller
 weight of food in proportion to their body size and also fewer prey
 items per night than do frugivores. Thus, gleaning carnivores should
 spend less time and energy transporting food items between foraging
 sites and roost sites (and in total foraging time) than do frugivorous
 bats. Time budgets based on radiotracking by Vehrencamp et al.
 (1977) confirm this hypothesis in the case of Vampyrum spectrum. It
 would be interesting to compare guilds in more detail in terms of
 searching effort devoted to foraging.
 Late in the wet season and in the dry season large insects are
relatively scarce, and some gleaning species change foraging patterns.
Several of the small- and medium-sized species become rare on the
island late in the wet season, but return and eat mixed diets of fruit
and insects through the dry season (Bonaccorso and Humphrey, in
prep.). Micronycteris megalotis and M. brachyotis appear to use this
strategy. Tonatia sylvicola, however, remains all year eating insects


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