Use of naturally and anthropogenically disturbed habitats in Amazonian rainforest by the teiid lizard Ameiva ameiva

Abstract

We studied the effects of natural and anthropogenic habitat disturbances on environmental temperatures and their consequent effects on thermoregulation and habitat use of Ameiva ameiva in a complex habitat matrix of primary tropical forest and several types of disturbed forest in Amazonian Brazil. Data on Ameiva ameiva from other regions in Brazil with habitats that have little canopy coverage are compared with data from rain forest sites to determine if activity of rain forest Ameiva is temporally or spatially limited by the thermal opportunities available in shaded environments. Ameiva ameiva preferentially used disturbed habitats in rain forest regions. These sites had significantly higher environmental temperatures than did surrounding undisturbed rain forest. Environmental temperature distributions indicate that the closed canopy rain forest is a thermally marginal habitat for Ameiva ameiva and that high temperatures resulting from forest clearing are likely to enable Ameiva ameiva to increase foraging activity in adjacent forest edges above what is possible in the continuous interior forest. Ameiva ameiva from rain forest, cerrado and savanna regions of Brazil had significantly lower body temperatures than Ameiva from caatinga, an open habitat type with little canopy coverage. This difference is probably due to high ambient temperatures and the high availability of basking sites in open habitats and suggests a thermal constraint on habitat use and time of activity for Ameiva in closed canopy habitats.