Abstract

Grouper spawning aggregations along deep reefs of the US Virgin Islands represent a large potential prey source for predators including sharks. To examine the relationship between grouper spawning aggregations and sharks, we tagged three species of groupers and three species of sharks with acoustic transmitters and monitored their movements over several years using an array of receivers deployed at spawning sites and at non-spawning locations along the southern shelf edge of St. Thomas, US Virgin Islands. Each species of shark demonstrated different behavioral patterns. Temporal and spatial patterns of movement of lemon sharks (Negaprion brevirostris) were closely associated with spawning events, but little connection between spawning aggregations and behavior of the other two species of sharks (Carcharhinus perezi , Galeocerdo cuvier). Our findings illustrate variable interactions that may occur between different species of sharks and grouper spawning aggregations and that prey availability may influence the spatial and temporal patterns of activity of co-occurring species of sharks in different ways.

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