Development of multispecies virtual population analysis (MSVPA), which assesses interspecific and intraspecific predation through an analysis of stomach contents, has verified the hypothesis that predation among exploited fish species contributes significantly to their natural mortality and that predation, and thus natural mortality, is inherently variable from year to year. In single-species virtual population analysis (SSVPA), natural mortality is assumed to be constant. MSVPA also suggests that natural mortality among Young fish after recruitment is much higher than previously thought. The method has considerable implications for management. |
