Spatial and temporal interactions of predators and prey

ICES (International Council for the Exploration of the sea) Advisory Committee on Fishery Management (ACFM) recently concluded that more information on the form and dynamics of predator-prey interactions is needed if multi-species fisheries management models are to advance significantly.

Spatial and temporal interactions of predators and prey is a Defra funded project, the aims of which are to integrate a number of field approaches and apply these to the study of predator-prey interactions. We are using acoustic and fishing techniques to assess the relative densities of cod and sandeels on feeding grounds, acoustic telemetry to monitor local movements of cod on their feeding grounds, and data storage tags to monitor the larger-scale movements of cod (PDF, 267 KB) between feeding grounds over extended (>1 year) periods. In addition, we are using benthic mapping techniques to determine sandeel-habitat associations, which has lead to the development of a novel acoustic methodology for assessing spatio-temporal dynamics of sandeels. Future work will include the development of methods for measuring the feeding activity of free-ranging predators.

This project is a novel development in the marine field. Few serious attempts have been made to study predator-prey dynamics in the field, and never before on such a large scale. So far, the project has already resulted in some exciting findings, particularly the definition of previously unknown behavioural dynamics of cod (see Nature 492, 156). In addition, surveys of sandeel populations on the Dogger Bank have revealed that stocks have very variable spatial and temporal dynamics at a range of spatial scales. The results feed into multi-species fishery models developed at Cefas and also into ICES Study and Working Groups.