Symposium Abstract: Benthic Perturbations from Walrus Foraging: Are They Similar to Trawling?
C. V. Jay, L. C. Huff, and R. A. McConnaughey
The Pacific walrus roots through soft sediment and feeds on a wide variety of benthic organisms, and in the process, they resuspend sediment and disturb much of the fauna in their path. Some of the consequences of walrus foraging may be similar to those produced from bottom trawling. In a preliminary study, we are using side-scan sonar images to identify walrus foraging tracks (furrows) in soft sediments to measure the distribution of foraging patches and the level of foraging effort of walruses in an area within Bristol Bay, Alaska. The approximate area affected and level of mechanical disturbance to the sea floor from walrus foraging are contrasted to those that might be expected to be produced from bottom trawling.