Lizard habitat partitioning on islands: the interaction of local and landscape scales


*Lauren B. Buckley, Department of Biological Sciences, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA.


Aim  This study addresses how species resolve environmental differences into biological habitats at multiple, interacting spatial scales. How do patterns of local habitat use change along an elevation gradient? How do patterns of local habitat partitioning interact with partitioning at a landscape scale?

Location  Northern and southern Lesser Antilles islands, West Indies.

Methods  We document how Anolis Daudin, 1802 lizards partition habitat locally at sites along a landscape-scale elevation gradient. We examine habitat partitioning both with and without interspecific interactions in the predominately flat northern Lesser Antilles islands and in the more mountainous southern islands.

Results  Anoles partition local habitat along perch-height and microclimate axes. Northern-group sympatric anoles partition local habitat by perch height and have overlapping distributions at the landscape scale. Southern-group sympatric anoles partition local habitat by microclimate and specialize in particular habitats at the landscape scale. In both the northern and southern groups, species use different perch heights and microclimates only in areas of species overlap along the elevation gradient.

Main conclusions  We demonstrate the interaction between local- and landscape-scale habitat partitioning. In the case of microclimate partitioning, the interaction results from the use of thermal physiology to partition habitat at multiple scales. This interaction prompts the question of whether habitat partitioning developed ‘local-out’ or ‘landscape-in’. We pose this dichotomy and present a framework for its resolution.