Influence of Aerial Azteca Nests on the Epiphyte Community of Some Belizean Orange Orchards

Abstract

ANTS ARE FREQUENTLY A MAJOR component of the invertebrate biomass and diversity of tropical forest canopies. Ant species building aerial nests made of papery or cardboard-like material called carton, are often numerically dominant among the ants (Madison 1979a, Wilson 1987, Davidson 1988, Tobin 1991). Certain epiphytes are largely restricted to aerial ant nests, i.e., obligate ant nest users (subsequently referred to as “obligate” or “ant garden” epiphytes), and many of them produce specialized ant-dispersed seeds to ensure dispersal to suitable substrates, ie., nests (Ule 1901a, b; Madison 1979a; Benzing 1990, 1991a, b). Consequently aerial ant nests with associated epiphytes have become known as “ant gardens”. Although it has been suggested that the relationship between the garden and the ants is casual (Wheeler 1921, Weber 1943), the most recent observations suggest that it is a complex mutualism in some epiphyte species at least (e.g., Kleinfeldt 1978, Madison 1979a, Beattie 1985, Davidson 1988, Davidson and Epstein 1989, Holldobler & Wilson 1990, Yu 1994).