Herbivore Damage to Three Tropical Ferns

Herbivore damage to fronds of Polybotrya cervina. Thelypteris turrialbae. and Adiantum obliquum from Finca La Selva, Costa Rica, was measured, and types of damage were distinguished. Herbivores removed 9.9, 5.5, and 7 3 percent of the leaf tissue, respectively The amount removed did not differ significantly among the species, although the proportion of fronds with different types of damage was different. In this study the levels of damage to ferns are similar to those reported for tropical angiosperms, suggesting that the vegetative parts of tropical ferns and angiosperms are utilized equally by herbivores. The variety of damage types suggests that tropical ferns host a varied insect fauna. These results support the hypothesis that underutilization of ferns by herbivores is largely an artifact of inadequate sampling.