Analysis of food habits data for over 60 fish species revealed a suite of previously unrecognized predators of northern shrimp in the Gulf of Maine.

A predation pressure index based on changes in predator biomass and occurrence of shrimp in each predator’s diet increased during the 1990s, and the predator field became dominated by relatively few species.

Using observed predation pressure to scale natural mortality in a stock assessment model used for management greatly improved a severe retrospective pattern in the model estimates.

The simple method for incorporating predation in stock assessment avoided the need for more data-intensive estimates of absolute consumption and total abundance of predators, which frequently are unavailable or difficult to quantify.