Life in the Slow Lane: Ecology and Conservation of Long-Lived Marine Animals

Abstract

<em>Abstract.</em> —Long-lived marine species are particularly vulnerable to human perturbations for reasons related both to the species’ demographics and human perception. Marine turtles provide an illustrative example: species delay maturity from 10 to as late as 30–60 years, and human monitoring of turtle populations focuses primarily on nesting adult females and nest production. Apparently marine turtles are trading early reproduction for later reproduction at a larger size, facilitating higher fecundity to overcome variable, often very high, natural mortality in eggs and early life stages. Human perturbations increase mortality of marine turtles at all life stages. However, population modeling has shown that annual survival of some stages, particularly large juveniles and adults, may be particularly critical to population maintenance and recovery. At the same time, monitoring focused on the larger, usually older, life stages of long-lived marine species may be a relatively poor indicator of actual population health and trends. High bycatch of long-lived marine species in long-line fisheries is outlined and concerns raised. Precautions, based on long-lived species’ vulnerability and the limitations of our ability to adequately monitor population status, should be built into management regimes.