Publication Abstract

Spatial and temporal predation patterns in the Celtic Sea

V.M. Trenkel, J.K. Pinnegar, W.A. Dawson, M.H. du Buit and A.N. Tidd

We investigated spatial and temporal feeding patterns of six major predators (cod, hake, lesser-spotted dogfish, megrim, saithe and whiting) on four prey species (blue-whiting, horse-mackerel, mackerel and Trisopterus spp.) in the Celtic Sea using stomach content and bottom-trawl survey data. We found some complementarity in the seasonal feeding patterns for blue-whiting on one hand and mackerel and Trisopterus spp. on the other hand. While blue-whiting was more often found in stomachs during the summer, mackerel and Trisopterus spp. were more present during the winter half year. In terms of spatial patterns, blue-whiting were consumed at the shelf edge in accordance to their higher densities, while mackerel, horse mackerel and Trisopterus spp. were eaten more often on the continental shelf again in agreement with their depth-density distribution patterns. While smaller predator individuals (and species) targeted Trisopterus spp. and blue-whiting, larger predators consumed horse-mackerel and mackerel. There was also some evidence for the matching of spatial density distributions (spatial collocation) of the predators cod, lesser-spotted dogfish and whiting with their common prey Trisopterus spp. and to a lesser degree and only in spring between the predators megrim and hake with the preys blue-whiting, horse-mackerel and mackerel.

Reference:

V.M. Trenkel, J.K. Pinnegar, W.A. Dawson, M.H. du Buit and A.N. Tidd, 2005. Spatial and temporal structure of predator-prey relationships in the Celtic Sea fish community. Marine Ecology Progress Series, 299: 257-268