Burbot Conservation Aquaculture at The Kootenai Tribe of Idaho s Hatchery 2 - Twin Rivers Hatchery

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1 Burbot Conservation Aquaculture at The Kootenai Tribe of Idaho s Hatchery 2 - Twin Rivers Hatchery KVRI Board Meeting 15October2018 Nathan Jensen njensen@kootenai.org

2 Some General Burbot Biology Burbot are the only cod that complete life in fresh water 1. Adults Group spawners 2. Eggs Semi-buoyant and very small (~1 mm) 3. Larvae 3-4 mm at hatch 4. Juveniles Cannibalism will occur E.Keeley

3 KTOI Hatchery 2-Twin Rivers Hatchery Location KTOI-H2 Twin Rivers

4 KTOI Hatchery 2-Twin Rivers Hatchery Plan View

5 Aquaculture Program Phases and Rearing Space 1. Adult, Egg collection 2. Egg incubation 3. Live feed culture 4. Larviculture 5. Juvenile rearing In general, adults/eggs come in January-February Burbot lab plan view Larvae/Juveniles out to specific locations April-September

6 Some Program Challenges 1. Production of burbot is variable annually 2. Larval burbot require live feeds 3. Procedures are time sensitive and labor intensive 4. Individual family separation is required 5. Multiple brood sources are used Kootenai River Moyie Lake (Broodsource population) In-hatchery parental tracking examples

7 Eggs From Kootenai River Adults 1. Hatchery broodstock are captured by IDFG in January and transported to KTOI-H2 by KTOI 2. Fish are sorted by size in hatchery and allowed to volitionally spawn 3. Eggs are collected daily during February Eggs being collected and stocked into incubators

8 Eggs From Moyie Lake B.C. 1. Adults are angled and netted through ice 2. Adults used are given a unique code and tissue sampled for genetic ID 3. Eggs are fertilized and transferred through US customs to KTOI-H2 daily; mid-february BCMoFLRO

9 Egg Incubation at KTOI-H incubator capacity Imhoff Cones 2. Target 5 million eggs from Moyie Lake; 15 million eggs from Kootenai River stock 3. Target temperature 2-3 C 4. ~40 days to hatch Example of egg incubator tank. Note 121K eggs in incubator on left

10 Burbot Larviculture 1. Densities vary by family; per Liter 2. No mouth for two weeks 3. Swim bladder inflation is a critical phase for survival 4. Live feed begins when mouth/swim bladder develop Two weeks Swim bladder 70K, 42% loss 56K, 20% loss

11 Live Feed Culture 1. Live prey are raised March-June (~100 days) 2. Rotifers are reared at high densities Target 10 Billion harvestable population 3. Artemia spp. are hatched daily during production season Million organisms are needed per day µ Rotifer 5. Note: we are experimenting with other native freshwater species µ Artemia

12 Live Diet to Cod Diet Food Transitions Algae + Rotifer Rotifer + Artemia Artemia only Artemia and Cod Diet Note: if burbot are released as larvae we do not need to transition to a dry diet

13 Juvenile Rearing 1. Bottom dwelling, prefer dark places 2. Numbers of fish vary due to family separation needs Size of fish also varies by family 3. After feed training complete mortality subsides but intense cleaning is required Example of size variation within a feed trained juvenile family group Size variation example within a year class

14 Survival Assumptions a Survival assumptions used to determine how many eggs would be needed to achieve a production goal of 126,000 Juveniles; 2% survival from egg to juvenile is our goal.

15 KTOI-H2 Juvenile Burbot Survival Estimates Production K K K K Points on figure represent program survival estimates

16 Release Locations Burbot Stocking Sites Kootenay Lake Goat River Boundary Cr Ferry Island Deep Cr Moyie River Bonner Lake Black dots on map indicate approximate burbot release locations KTOI-H2

17 BURBOT RELEASES ( ) BEFORE KTOI- H2 TWIN RIVERS HATCHERY ID = 117,142

18 JUVENILE BURBOT RELEASES ( ) TWIN RIVERS TOTAL = 530,000 BC = 182,000 BORDER = 104,000 ID = 244,000

19 ALL JUVENILE BURBOT RELEASES COMBINED ( ) OVERALL SINCE 2009 =647,142 BC = 182,000 BORDER = 104,000 ID = 361,142

20 Release numbers since 2009 Fish Year

21 Release numbers since 2009 *

22 Summary 1. Expect high mortality and variability among year classes Compensate with high egg numbers Insure year-class representation using larval releases 2. Live feeds required Must establish feeds a minimum of three weeks ahead of feeding larvae Labor intensive (75% of labor during this phase) 3. Hatchery burbot larvae will survive after release in the Kootenai/y system May be able to use this to reduce production cycle time/costs Transition to artificial diet may not be necessary; more natural 4. Currently juvenile rearing required for releases in BC, disease testing, IDFG modeling

23 Kootenai Valley Resource Initiative Kootenai Tribe of Idaho Fisheries and Wildlife Program Bonneville Power Administration (FUNDING) Northwest Power and Conservation Council BC Ministry of Forests, Lands & Natural Resource Operations Idaho Department of Fish and Game Montana Fish Wildlife and Parks United States Army Corps of Engineers United States Fish and Wildlife Service United States Geological Survey Idaho Department of Environmental Quality Idaho Department of Water Resources Idaho Office of Species Conservation Natural Resource Conservation Service United States Forest Service Bureau of Land Management University of Idaho-Aquaculture Research Institute Bonners Ferry Builders Good Fellow Brothers Inc.