Effect of species interactions on landscape abundance patterns

Authors


Lauren B. Buckley Department of Biological Sciences, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA. Tel.: (650)7234365; Fax: (650)7236132; E-mail: lbuckley@stanford.edu

Summary

  • 1We develop a process-based bioenergetic model that incorporates population dynamics to predict the abundance trends for Anolis lizards along elevation gradients in the Lesser Antilles islands. Model outcomes are compared with empirical abundance trends on islands with and without species interactions and with differential topography.
  • 2The bioenergetic model incorporating body size, thermal physiology and prey abundance qualitatively predicts how lizard abundance declines with elevation for solitary anole species. Empirical elevation trends on northern and southern one-species islands have similar slopes but different intercepts at sea level. The greater anole abundance on the southern islands is predicted by the model when parameterized with the empirically observed higher insect abundance.
  • 3Anole abundance patterns on two-species islands diverge from the bioenergetic model predictions. One species is more abundant at sea level and the other more abundant at higher elevations compared with the trend for solitary anoles. Species interactions modify population responses to elevation gradients.

Ancillary