multiple years of sampling to mark and recapture individuals completed between 2006 and 2008 ...
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Multiple years of sampling to mark and recapture individuals completed between 2006 and 2008
Despite significant effort, population estimates were not as precise as hoped - Peterson and Jolly-Seber estimates showed significant differences for the same time periods
A small number of marked fish recaptured, insufficient mixing of tags between samples for Peterson estimates, and potential trap avoidance for Jolly-Seber estimates were potential problems
Given the constraints noted above, we evaluated all the data and established a population estimate that reflected the most likely compromise.
Population assessments suggest a population size of ~ 2500-4000 in both basins of Moyie Lake combined.
North Moyie – 1500 to 2500 adult burbot South Moyie – 1000 to 1200 adult burbot
Moyie Lake Stock StatusMoyie Lake Stock Status
Moyie Lake Angler UseMoyie Lake Angler Use
2007 2008
fishery almost entirely through icefishery almost entirely through ice
used trail cameras and angler interviews to track effort in 2007 and 2008used trail cameras and angler interviews to track effort in 2007 and 2008
Significant change in timing and location of angler effort in 2008Significant change in timing and location of angler effort in 2008
Fishery was “discovered” in 2008, with effort on spawning concentrations during the daylight Fishery was “discovered” in 2008, with effort on spawning concentrations during the daylight hours with significantly higher catch rateshours with significantly higher catch rates
Moyie Lake – Creel Survey and Fishery ManagementMoyie Lake – Creel Survey and Fishery Management
Fishery impacts could be a concern in this developing fishery and are being Fishery impacts could be a concern in this developing fishery and are being tracked. tracked. – 2007 - caught 515, harvested 1682007 - caught 515, harvested 168– 2008 – caught 1089, harvested 360 (may be an under-estimate of both effort 2008 – caught 1089, harvested 360 (may be an under-estimate of both effort
and catch)and catch)– Based on population estimates, this represents an annual exploitation rate of Based on population estimates, this represents an annual exploitation rate of
14-24%14-24%– Modeling of the historic Balfour burbot population suggests exploitation Modeling of the historic Balfour burbot population suggests exploitation
rates of 20% may have been sustainable for that populationrates of 20% may have been sustainable for that population
New regulations are being implemented this winter (time period closure) to allow New regulations are being implemented this winter (time period closure) to allow some recreational opportunity, reduce the possibility for over-harvest, and limit some recreational opportunity, reduce the possibility for over-harvest, and limit the exposure of spawning congregations to recreational anglingthe exposure of spawning congregations to recreational angling
Moyie Lake spawning locations identified in 2008 (creel info suggests spawning as early as the last week of January, Moyie Lake spawning locations identified in 2008 (creel info suggests spawning as early as the last week of January, and as late as the last week of February)and as late as the last week of February)
KTOI and MoE staff completed two trips to Moyie, the first we identified spawning sites, while the second was KTOI and MoE staff completed two trips to Moyie, the first we identified spawning sites, while the second was targeted on collecting gametes for fish culture activitiestargeted on collecting gametes for fish culture activities
We were successful in collecting sperm (50+ samples in one day) and KTOI staff established high motility using We were successful in collecting sperm (50+ samples in one day) and KTOI staff established high motility using extender after 1 week.extender after 1 week.
Although one ripe female was collected on the first trip, none were collected when we attempted to collect gametes Although one ripe female was collected on the first trip, none were collected when we attempted to collect gametes on the second tripon the second trip
New capture methods will be employed in 2009 when we again attempt to provide gametes and should improve our New capture methods will be employed in 2009 when we again attempt to provide gametes and should improve our catch of femalescatch of females
Moyie Lake Burbot BiologyMoyie Lake Burbot Biology
Spawning congregation observed on Moyie Lake – Spring 2008Spawning congregation observed on Moyie Lake – Spring 2008
Moyie Lake Burbot BiologyMoyie Lake Burbot Biology
Next steps:Next steps:
– monitoring donor population (ongoing assessments of angling effort and monitoring donor population (ongoing assessments of angling effort and population strength)population strength)
– refining methods for providing broodstock while minimize impact to donor refining methods for providing broodstock while minimize impact to donor stock (ie. capture, spawning and release at spawning location instead of stock (ie. capture, spawning and release at spawning location instead of removal and captive stock)removal and captive stock)
– provide up to 3 million fertilized eggs to U of I for fish culture experimentsprovide up to 3 million fertilized eggs to U of I for fish culture experiments
Turning the Tides - Turning the Tides - Burbot Recovery EffortsBurbot Recovery Efforts
Funding for this work provided by:Funding for this work provided by:
•Kootenai Tribe of Idaho and Idaho Dept of Fish and Kootenai Tribe of Idaho and Idaho Dept of Fish and Game through the Bonneville Power Administration Game through the Bonneville Power Administration (Northwest Power and Conservation Council’s Fish And (Northwest Power and Conservation Council’s Fish And Wildlife Program)Wildlife Program)
•BC Mountain Pine Beetle FundBC Mountain Pine Beetle Fund
•BC Ministry of EnvironmentBC Ministry of Environment