The objective of this study is first to assess whether the distribution of a marine predator can be explained by the distribution of its prey, and secondly, whether it can also be explained by abiotic proxies for prey distribution. More specifically, using telemetry data we study how the spatial distribution of grey seals (Halichoerus grypus) in the North Sea correlates with the observed, and predicted distribution of their major prey, the sandeel (Ammodytae).
Although this study reveals that grey seals prefer sandeel grounds, the model-based estimates of sandeel occupancy based on sediment type and depth was better at explaining variation in grey seal density within and around the sandeel grounds. The better explanatory performance of the prey habitat model may be due to the more extensive and better-resolved data for the abiotic covariates in contrast with the stochastic nature of prey survey data,. Also, abiotic variables may be correlated with additional important prey characteristics such as quality and catchability.
|Published - 1 Mar 2014
|28th Conference of the European Cetacean Society: Marine mammals as sentinels of a changing environment - University of Liège, Liège, Belgium
Duration: 5 Apr 2014 → 9 Apr 2014
|28th Conference of the European Cetacean Society
|5/04/14 → 9/04/14