The purpose of this research was to study the effects of habitat fragmentation on pollination and reproduction of Ruellia succulenta Small (Acanthaceae). Many studies have documented reduced seed set in plants occurring in fragments relative to plants in continuous habitat. The mechanisms explaining this reduction in reproduction have generally been resource limitation, pollinator limitation, and genetic erosion/inbreeding depression. My study focused on resource and pollinator limitation. I chose three sites in each of the following four size classes of habitat: small (< 3 ha), medium (3-9 ha), large (> 10 ha), and intact (in Everglades National Park). At each site, 20 randomly chosen plants were tagged. All plants were surveyed weekly for a year and data were collected on # of open flowers, # of mature fruit, # of seeds/fruit, and seed predators/fruit. If present, stigmas from untagged plants were mounted in Fuchsin gel on microscope slides. These were analyzed for number of conspecific and heterospecific pollen grains. If open flowers were present, timed pollinator watches were performed. Number and identification of floral insect visitors were recorded. The results of the ANOVA test on area of site and the three reproductive variables all were highly significant but the trend of reduced reproduction in smaller size classes was not shown. All three reproductive variables had highly significant negative Spearman rank correlations with the factor time since last fire. There appeared to be no correlation between conspecific/heterospecific pollen on stigmas (indirect measure of pollination) and either area of site or time since last fire. There were highly significant differences in the proportion of the orders of flower visiting insects by site. In conclusion, reduced seed set appeared to be the result of resource limitation (light and nutrients) rather than pollinator limitation. Fragmentation did, however, affect the composition and abundance of the pollinator guild.

Key words: fragmentation, pollination, pollinator guilds, Ruellia succulenta, seed set