VARIATIONS IN MORTALITY OF A CORAL-REEF FISH - LINKS WITH PREDATOR ABUNDANCE

The mortality rates of a pomacentrid Acanthochromis polyacanthus were examined in relation to the abundance of large predatory fish (> 200 m m total length, TL) at two spatial scales. Survivorship was negatively related to patterns of predator abundance at a large spatial scale (h undreds of metres) over 3 yr, but not at a small spatial scale (tens o f metres) over 2 yr. On the large scale, mortality was consistently gr eater (14 to 30%) in locations where there were greater numbers of pre dators, and lower in locations where predators occurred in smaller num bers. Among these locations, spatial differences in rank abundance of surviving juveniles were primarily due to mortality, whereas temporal differences in rank abundance were primarily due to initial juvenile a bundance. These data suggest that impacts of large predatory fish were likely to have been greater in space than time and at the large spati al scale than the small spatial scale.