Ecology and conservation of bat assemblages associated with water-filled sinkholes (cenotes) in the Yucatan Peninsula, Mexico

In the Yucatan, cenotes or water-filled sinkholes fonned by the dissolution of limestone and surrounded by a characteristic dense layer ofheterogeneous vegetation, are the main sources of water for humans and animal assemblages. I investigated the importance of cenotes and their surrounding vegetation for bats by comparing the assemblage structure and diversity between forest and pastureland, with and without cenotes. I set ground level mist nets, sub-can.6py nets and harp traps and recorded the ultrasonic calls of flying bats for 96 nights in 2003-2005. Capture and acoustic methods recorded a total of 37 species in six families. Accumulation curves demonstrated that I sampled most of the species likely to be recorded. Forest sites had a greater bat species diversity and abundance than pastureland, as well as more rare and threatened species. Forest sites with and without cenotes had a similar bat assemblage structure and diversity, whereas in pastureland there was a greater species diversity and abundance and number of rare and threatened species at cenotes than at sites without cenotes. Cenotes in the pastureland landscape attracted an abundance of frugivores which fed on 27 plant species from 13 families. In addition, the highest number of passes and feeding buzzes of insectivorous bats was recorded at cenotes in pastureland. One species, Pteronotus personatus, represented a new record for the Yucatan bat fauna. Chrotopterus auritus and Micronycteris schmidtorum, both of which are listed by the Mexican government as threatened species, together with Eptesicus furinalis, Eumops underwoodi and P. personatus, were recorded only at cenotes. In Yucatan's agricultural landscapes, protection of cenotes and their characteristic vegetation is, essential not only for the conservation of bat diversity but also because they represent potential seed sources for the regeneration of the lowland forest, in which bats play key roles as pollinators and seed dispersers. Key words: Chiroptera, deforestation, echolocation, forest, frugivorous bats, insectivorous bats, habitat use, pastureland, pollination, seed dispersal, water resources.EThOS - Electronic Theses Online ServiceGBUnited Kingdo