Integrating behaviour into wildlife conservation:: the multiple ways that behaviour can reduce Ne

There has been a recent interest in integrating an understanding of behaviour into conservation biology. Unfortunately, there has been no paradigm for such a process. Without a clear framework for integration, conservation biologists may have difficulties recognising how behavioural knowledge can help solve real-world conservation problems. Effective population size (N-e) is a key demographic parameter used to understand population viability. A variety of behaviours and behavioural traits impact N-e,N- yet their importance for conservation is under-appreciated. We suggest that identifying behavioural traits that affect N-e provides a paradigm for integrating behavioural biology into conservation biology. Behaviour can affect N-e through at least three different mechanisms: reducing N - the population size; reducing r - the population growth rate, and/or by increasing reproductive skew. We discuss how nine common behavioural traits can reduce N-e, and suggest how an understanding of these traits may inform management of both free-living and captive animals. (C) 2000 Elsevier Science Ltd. All rights reserved.