Land management impacts on tree hole invertebrate communities in a Neotropical rainforest

Background/Question/Methods: The Los Tuxtlas Biosphere Reserve in Southeastern Veracruz, Mexico represents the northernmost Neotropical lowland rainforest and has lost 84% of its forests in the last forty years. Rich terrestrial and aquatic species communities are found throughout Neotropical forests, habitats increasingly threatened by land management practices. Plant-held waters, Phytotelmata, are ecologically important discrete microhabitats harboring many specialist invertebrates and are abundant in tropical forests. In this study, using artificial tree holes, we examined invertebrate tree hole communities in mature forest of Los Tuxtlas and in a managed habitat adjacent to the station. Based on the proximity of human and livestock communities to managed habitats and the dispersal limitations of some phytotelm specialists, we expected to find community composition differences between the two habitats.

Results/Conclusions: We found distinct differences in chironomid colonization; Tanypodinae, a predaceous subfamily, was present in the managed habitat and its omnivorous counterpart, Chironominae, was present in the forest. We found differences in mosquito colonization with more predaceous Toxorhychites in the managed habitat. Haemagogus mosquitoes were only present in the managed habitat. These results indicate different colonization ability across phytotelmata specialists and warn of larger community shifts and potential public health hazards with continued and intensified forest fragmentation and degradation.