How to translate text using browser tools
26 February 2010 The Influence of Landscape Heterogeneity and Dispersal on Survival of Neonate Insular Iguanas
Charles R. Knapp, Silvia Alvarez-Clare, Caro Perez-Heydrich
Author Affiliations +

The relationship between dispersal and predator–prey interactions in heterogeneous landscapes is an underappreciated factor influencing species persistence. This relationship, however, is critical for understanding population dynamics and for implementing management strategies for species. We investigated the influence of habitat heterogeneity and dispersal patterns on neonate survival for the iguana Cyclura cychlura cychlura inhabiting Andros Island in the Bahamas. Contrary to our hypothesis, there was a clear survival advantage for neonates that spent more time in open mangrove habitat than relatively more closed-canopy habitats, most likely because of fewer primary predators in mangroves relative to other habitats. Snake predation was the most significant cause of mortality for neonates dispersing away from nest sites and was highest during the first week after release. The probability of survival to 28 days ranged from 16.7 to 28.4%. Most neonates displayed rapid, nearly linear movements away from nests for a minimum of 14 to 21 days. Mean straight-line distance away from nest sites for surviving neonates was 601 m. There was a significant positive relationship between mean daily movement rates away from nests and days survived. We suspect that the initial and rapid movements away from nests reduce relative predation by dispersing neonates from a zone where predators learn to exploit them. Our results have implications for translocation programs targeting endangered insular iguanas throughout the Neotropics because historically only the presence of non-native mammalian predators was used as a metric to evaluate potential translocation sites.

2010 by the American Society of Ichthyologists and Herpetologists
Charles R. Knapp, Silvia Alvarez-Clare, and Caro Perez-Heydrich "The Influence of Landscape Heterogeneity and Dispersal on Survival of Neonate Insular Iguanas," Copeia 2010(1), 62-70, (26 February 2010).
Received: 16 January 2009; Accepted: 1 October 2009; Published: 26 February 2010
Get copyright permission
Back to Top