Cameron W. Barrows. Center for Natural Lands Management, P.O. Box 188, Thousand Palms, CA 92276.
Most biological monitoring focuses on some measure of the status of a target organism.
Without understanding and measuring potential causal factors for population change, such monitoring programs will fail to provide information as to what and when remedial management actions are indicated. For 15 years, populations of the Coachella Valley fringe-toed lizard, Uma inornata , a state endangered and federally threatened species, have been monitored near Palm Springs, California. Through measuring reproductive success rates in the lizard, and determining factors that are responsible for changes in that reproductive success, a model for predicting adult population fluctuations can be developed. When fluctuations are inconsistent with the model' s predictions, alternative causal factors need to be explored. If those causal factors are anthropogenic and result in a negative population trajectory, then management responses can be focused on appropriate perturbations.