Feeding is an important component in consumer-resource interactions of population-community ecology and in energy and nutrient transfers of ecosystems ecology (Bengtsson 1998). Food webs are used to describe the complexity of feeding interactions. The level of omnivory of the members of an ecosystem can influence food web dynamics, interspecific interactions, and trophic structure (Morin and Lawler 1996, Polis and Strong 1996). Omnivory is defined as feeding on more than one trophic level (Pimm and Lawton 1978). Anolis lizards are the most abundant and conspicuous components of the diurnal community in the Caribbean Islands, (Williams 1969). Although considered strict insectivorous, some species add fruits to their diet (Herrel et al. 2002). Given the uncertainty about the trophic ecology of anole lizards, detailed studies about the level of omnivory/frugivory, trophic position, as well as their role as dispersal agents it is necessary to comprehend the role of this group in the dynamic and structure of food webs and in ecosystem function. We present field observations and preliminary data about omnivory/frugivory of Puerto Rican anole lizards. This data is part of the research being developed to determine their degree of omnivory in Puerto Rico and their possible role as seed dispersers in forests on karst with different ecohydrological dynamics.