Rising land falling fishery: the effects of isostatic rebound and rapid succession on east Alsek River sockeye salmon

Abstract

This thesis includes research conducted in the Dry Bay Preserve of Glacier Bay National Park in 2005 and 2006 for the U.S. National Park Service. The research mission was to determine the cause of collapse in the East Alsek commercial sockeye fishery. The focus of the study was to determine if the collapse was due to human caused events or if there was a broader ecological basis for the recent downturn in returning sockeye. The East Alsek had undergone a dramatic decline in returning sockeye in recent years and the changing quality and quantity of habitat was thought to be the culprit for this downturn. However, fishery records and other environmental variables were also examined in order to establish a retrospective association between reduced production, ambient environmental conditions, and commercial fishing. The research for this thesis was funded by the U.S. National Park Service under the request of the City and Borough of Yakutat.