Estimating Burbot Population Sizes in Alberta Lakes, 2022–2024
Interim Report
Author(s)
Nikita Lebedynski, B.Sc., M.Sc., P.Biol.
Summary
In Alberta, burbot (Lota lota) has typically been undervalued as a sport fish and before 2017 the flesh could legally be wasted. Unlike most sport fish that are protected during their spawning season, burbot angling is particularly popular when they congregate for spawning in the winter. Burbot are present in all fisheries management zones of Alberta with most waterbodies having a general bag limit of ten fish of any size and 19 waterbodies having specific regulations between zero and three fish. Given the current and increasing interest in burbot angling, it is important to develop burbot monitoring methodologies in Alberta. We conducted burbot population estimates at multiple lakes using cod traps to support our long-term goal of creating a model to increase our efficiency with population monitoring.
In 2022, we performed two pilot surveys where we successfully used cod traps to capture burbot at Peerless and Musreau lakes. We caught 12 burbot at a rate of 0.44 fish/trap/24-hours at Peerless Lake. We caught 27 burbot at a rate of 0.41 fish/trap/24-hours at Musreau Lake. We gained an understanding of mortalities caused by hypoxia and barotrauma, and we determined cod traps would be appropriate for mark-recapture population estimates.
We performed multiple mark-recapture programs using cod traps at Musreau Lake in 2023, and at Lac Sante and Lac Ste. Anne in 2024. Gill nets and set lines were used on the final event at Musreau Lake. We captured 873 burbot at Musreau Lake made up of 786 from cod traps (0.85 fish/trap/24-hours), 83 from set lines (0.18 fish/hook/24-hours), and four from gill nets (0.40 fish/gill net/24-hours). We captured 551 burbot (0.75 fish/trap/24-hours) at Lac Sante and 25 (0.04 fish/trap/24-hours) at Lac Ste. Anne.
At Musreau Lake we estimated the burbot population to be 786 (95% Confidence Interval [CI] = 732–855), corresponding to 1.39 burbot/hectare (ha). At Lac Sante we estimated the population to be 4,661 (95% CI = 3,210–6,898), corresponding to 4.15 burbot/ha. We were unable to estimate the population at Lac Ste. Anne due to low captures and zero recaptures.