BULLETIN FLORIDA STATE MUSEUM


 INTRODUCTION
 The words "tropical forest" typically engender visions of species-
 rich communities, complex competitive interactions, and relatively
 stable environments. Indeed, faunal lists in the tropics are large, and
 food webs are intricately complex. It is also true that organisms in-
 habiting tropical lowlands usually are subjected to less extreme en-
 vironmental fluctuations than are their counterparts in temperate or
 polar regions. However, it is too infrequently emphasized that even
 species in tropical forests must possess behavioral flexibility to
 counter and survive climatic and biotic environmental change. There
 are two major reasons for this oversight. First, few detailed studies of
 tropical organisms have spanned periods of several years or even
 seasons, and second, behavioral responses of tropical species to en-
 vironmental fluctuations are often quite subtle. Whereas temperate
 animals commonly exhibit obvious and dramatic responses to seasonal
 change such as hibernation or long distance migration, tropical species
 may need only to switch food types or microhabitats, or briefly halt
 reproduction (Kaufmann 1962, Wolf 1970, Mares and Wilson 1971a,
 Snow and Snow 1972, Orians 1973, Montgomery and Sunquist 1973).
 Nevertheless, genetic and behavioral flexibility are requisites of sur-
 vival for most tropical as well as temperate species.
 Tropical bats are particularly good subjects for studies of diversi-
 ty, competitive interaction, and response to environmental fluctuation
 because of their individual abundance and the complex taxonomic and
 ecological communities they form. About 100 species of bats occur in
 each of the small countries of Central America (Hall and Kelson 1959).
 It is common to find 30 to 50 species in one macrohabitat measuring a
 few square kilometers in area.
 Among tropical bat species, few are known or suspected to
reproduce year round or to specialize on constantly abundant food
resources; the common vampire bat, Desmodus rotundus, being a
notable exception on both counts (Wimsatt and Trapido 1952, Turner
1975). Most bats in equatorial regions are seasonally polyestrous or
monestrous in reproduction (Baker and Baker 1936, Mutere 1970,
Fleming 1973) and make seasonal shifts in diet (Wilson 1971b, Flem-
ing et al. 1972, Heithaus et al. 1974).
 The objective of this paper is to delineate adaptive strategies used
by tropical bats that enable them to survive and reproduce under fluc-
tuating environmental conditions and coexist with numerous similar
species in complex communities. The field work represented herein
documents seasonal changes in food resources, mechanisms of
resource partitioning, and reproductive timing through one complete
year and portions of two other years.


Vol. 24, No. 4