Seasonal Distribution and Biological Characteristics of Dolly Varden in the Goodnews River, Togiak National Wildlife Refuge, Alaska, 2005-2006

摘要

The seasonal distribution of Dolly Varden Salvelinus malma was investigated in the Goodnews River using radio telemetry from August 2005 to June 2006. A total of 1,091 Dolly Varden were captured by seine or angling. Most (N = 1,024) of these fish were marked with individually number tags and released. Sixty mature Dolly Varden were implanted with radio transmitters between 24 July and 21 August 2005. Radio-tagged fish were relocated during 18 aerial tracking flights conducted between 1 August 2005 and 6 June 2006. Suspected spawning locations were identified for 49 (81.7 percent) radio-tagged Dolly Varden. The final fate of five (8.3 percent) transmitters is unknown leaving 55 transmitters that can be accounted for. Twenty-four fish (43.6 percent) survived spawning and overwintered in the Goodnews River watershed. Sixteen (29.1 percent) fish appeared to survive throughout the study. Fifteen fish are presumed to have emigrated from freshwater to the ocean between 22 May and 6 June 2006. Three (0.3 percent) of the 1,024 individually marked fish were reported caught in sport fisheries occurring in other drainages in southwest Alaska during the summer of 2006. These drainages included the Kulukak, Kanektok, and Aniak rivers which are located between 170 km and 510 km from the Goodnews River.