Symposium Abstract: Effects of Ice Gouging on Community Structure and the Abundance of Pacific Halibut Hippoglossus stenolepis: Disturbance Does Not Necessarily Mean Negative Fisheries Effects
P. N. Hooge, P. R. Carlson, and G. R. Cochrane
Side-scan sonar and multbeam imagery of Glacier Bay, Alaska, revealed complex iceberg gouge patterns at water depths to 135 m on the floor of Whidbey Passage and south to the Bay’s entrance. These previously undiscovered gouges formed more than 100 years ago as the Little Ice Age glacier retreated rapidly up Glacier Bay. Gouged areas supported greater biodiversity than nearby ungouged areas or sediment-filled gouges, probably due to increased habitat complexity. Small Pacific halibut Hippoglossus stenolepis were found more frequently in gouged areas, presumably due to higher prey abundance. These results contrast with the disturbance effects of recent, shallow ice gouging on community composition observed in the Arctic.