| During a nine month field study, we assess the ability of spider (Ateles geoffroyi) and howler (Alouatta pigra) monkeys to cross a large Mesoamerican river, and if this behavior is related to deforestation and/or human population size on the disturbed riverbank. The study was conducted along the Lacantún River, southern Mexico, which .divides the Montes Azules Biosphere Reserve and the Marqués de Comillas disturbed region. We collected data on river crossings by both monkey species from 428 hours of surveys along the river and 58 questionnaires completed by knowledgeable local informants. Furthermore, we determined the frequency of river crossing by the two species, location and direction of river-crossing, bank-to-bank river width at the location of... |
