| Abstract/Description or Keywords |
The Kitwanga River is biologically rich, supporting populations of all six species of salmon found in North America, as well as various species of resident salmonids and coarse fish. A species of significant importance in the Kitwanga River is sockeye salmon. Historically, Kitwanga sockeye numbered in the tens of thousands, and were actively fished for sustenance purposes by the Gitanyow and the Gitwangak who inhabited the watershed. However, drastic declines in stock abundance were observed in the 1960’s and today the stock is no longer fished for Food, Social or Ceremonial purposes because of conservation concerns. Kitwanga sockeye are an evolutionary significant unit as defined by Waples (1995) and therefore an important fisheries management unit. This suggests that Kitwanga sockeye have developed specific life history adaptations and timing regimes that are genetically unique and there is little possibility that neighbouring sockeye populations could replace Kitwanga sockeye naturally, given the extremely limited gene flow and the degree of local adaptation. The Kitwanga sockeye stock is currently at a depressed level and at risk of collapse. The collapse of Kitwanga sockeye could lead to extinction, which should be considered irreversible. The reasons for the stock decline are not completely understood, however it is believed that over-exploitation in the commercial fishery and habitat deterioration in Gitanyow Lake are the main contributors to the stock collapse. Fishery re-constructions for the last 40 years show average exploitation rates on Kitwanga sockeye of over 50%, reaching highs of over 65% in some years. Furthermore, the Kitwanga Watershed was heavily logged beginning in the 1960’s and it is believed that both spawning and rearing areas have been negatively impacted by road building and harvesting activities. |
