Status of Walleye (Sander vitreus) Fishery in Orloff Lake, Alberta, 2004
Bill Patterson and Stephanie R. Grossman
To aid in the management and recovery of Alberta's walleye stock at Orloff Lake, the Alberta Conservation Association (ACA) conducted a Fall Walleye Index Netting (FWIN) survey on 1 to 4 September 2004. The purpose of this survey was to collect data for the ongoing assessment of the walleye fishery at this lake. Fall Walleye Index Netting provides an estimate of the both fish abundance and population structure and is used to assist Alberta Sustainable Resource Development (ASRD) in the sustainable management of the sport fishery.
Results from te 2004 survey indicate that walleye in Orloff Lake exhibited a bimodel age-class distribution and the fishery was primarily supported by two abundant multi-year classes originating between 1990-1994 and 2000-2004. The presence of the 2000-2004 year-calsses suggests that moderate recruitment to the breeding population can be expected in the next 2-4 years. Our data also showed that the walleye fishery was composed of moderately fast growing fish with females maturing two years earlier than males; all females were mature at age 6 compared to age 8 from males. The estimated catch rate of walleye ranged from 18.5 - 28.7 walleye/100 m2/24 h (95% CI; n = 224) with a maximum likelihood estimate (MLE) of 23.0 walleye/100 m2/24 h. These catch rates are considered to be moderately high compared to other walleye fisheries in Alberta.