250 likes | 508 Views
Cory Williamson Fisheries Biologist Ministry of Environment Chair Nechako TWG. Overview-Update on NWSRI. Background Population Status/ History Recovery Efforts/ Updates on recent work Recovery Strategy. Nechako. White Sturgeon. Communities. Known Habitat. 1 st Nations Records.
E N D
Cory Williamson Fisheries Biologist Ministry of Environment Chair Nechako TWG
Overview-Update on NWSRI • Background • Population Status/ History • Recovery Efforts/ Updates on recent work • Recovery Strategy
Nechako White Sturgeon Communities Known Habitat 1st Nations Records Occasional Use Stuart Lake Skins Lake Spillway Kenney Dam Nechako Reservoir Takla Lake N Trembleur Lake FORT ST. JAMES Fraser River Stuart River FRASER LAKE VANDERHOOF PRINCE GEORGE Nechako River Flow Flow Flow Fraser River 0 12.5 25 50 75 100 Kilometres' QUESNEL
Status of Nechako White Sturgeon • Ongoing Recruitment Failure/ Ageing Stock • virtually no wild juveniles • < 25 caught under 1-m since 1995) • Small population (300-500) mostly adults • Genetically distinct from Upper Fraser • Slow Growth / low productivity habitat • Late maturity ~30-40 years for females ~15-20 for males
Nechako (Juveniles Up to 1 m) ( <15 years old?) 33 cm Photo: CSTC 35.3 cm Photo: CSTC
History of Recruitment Failure • Nechako River was dammed and flows diverted in 1952 (Kemano) • Successful recruitment continued until- about 1967. • Recruitment failure likely habitat related • Likely just post hatch- first few months • Likely related to Cheslatta River avulsions (1967; 1973) (McAdam et al. 2005)
ProjectedPopulation TrendHow Much Time is Left to recover the population Photo: Golder Associates 1999- ~571 2007- 380 2016- 240
History- NWRSI • Field-work 1995-1999 identified Nechako stock in trouble • 2000- Start of Recovery Planning Recovery Team and Action Planning Group Formed • Late 2003 COSEWIC recommendation for listing under the federal Species at Risk Act (SARA ) • 2004 Recovery Plan Completed- 2004 • 2005- Basin TWG/CWG - National Recovery Strategy • 2006- Nechako White Sturgeon Listed “Endangered” under Schedule 1 of SARA • Status- Endangered- August 15, 2006
Recent Program Successes • Two confirmed spawning events at Vanderhoof • May 18, 2004 (22 adults in area) • One wild juvenile captured, reared and released • May-June 2006 (numerous adults) • 8 wild juveniles reared and released • Numerous wild eggs caught • 4200 hatchery juveniles tagged released Triton-2004
Numerous Fish Multiple Pairings Several Fish, Some Paired Occasional Single Fish Egg Capture Site Sturgeon Larvae Captured Spawning Observed Triton- 2004
Recent successes continued. • Captured several mature males and 2 females in 2006. • Pilot hatchery to rebuild Nechako stock • Source of sturgeon larvae for recruitment failure diagnosis
Recent successes continued. • Habitat work continues • Refinement of our understanding of recruitment failure: • juvenile behaviour- preference for low velocities and clean gravels • habitat requirements.
Flow = 600 cms Flow = 614 cms, 1951
Stewardship “August 2005 Stuart Released” 250 Attended Stuart-30 cm August 2005
Adult ReleaseMay-2006240 lbs- 81 years old 400+ -Attended
“September 2006”- BC Rivers Day Music Festival3000+ Attended
Stewardship “October 2006”- 1000+ Sturgeon- Ambassadors 4200 Sturgeon Released!
2007 Projects • Recruitment failure diagnosis • Spawning timing/location/ rearing success • Habitat improvements - in-river gravel treatments/ behavior tests • Stewardship work with First Nations Fishers • Carrier Sekani Tribal Council- Community Outreach
2007 Projects • Juvenile monitoring • Movements, growth and survival • Habitat use • Enhanced pilot hatchery • More capacity- larger releases to meet preliminary release targets • Source of larvae for recruitment failure diagnosis
Freshwater Fisheries Society of BC • Golder Associates • Lheidli T'enneh Band • Nechako River Alliance • Nechako Watershed Council • Saikuz First Nation • School District 57 • Sport Fishers • Spruce City Wildlife Association • Tl'azt'en Fisheries Program • Triton Environmental Consultants • Alcan Primary Metal • BC Ministry of Environment • BC Wildlife Federation • Carrier Sekani Tribal Council • City of Prince George • District of Vanderhoof • Federation of BC Naturalists • Fisheries and Oceans Canada • FORREX • Fraser Basin Council • Fraser River Sturgeon Conservation Society www.nechakowhitesturgeon.org
Recovery Objective • To ensure the persistence and viability of a naturally-reproducing population of white sturgeon in the Nechako system and restore opportunities for beneficial use, if and when feasible.
Strategies for Recovery • Reduce or eliminate un-natural adult mortality • Re-establish natural recruitment • Rebuild population to preserve genetic integrity and restore population structure • Adaptive management and aggressive research
TWG- facility requirements • Annual releases of juveniles for up to 10 families • Rebuild population • Preserve genetic diversity • Source of juveniles (larvae) for research
TWG- Priorities • Conservation Fish Culture • Brood-stock capture • Juvenile releases • Long-term juvenile monitoring to refine release goals and adult population target • Critical Recovery Actions • Recruitment failure diagnosis • Habitat: behaviour studies, flow modeling, engineering and habitat restoration