Stuart Area Sockeye Salmon Runs and their Importance to the First Nations of the Upper Fraser River Watershed

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1 Stuart Area Sockeye Salmon Runs and their Importance to the First Nations of the Upper Fraser River Watershed Upper Fraser Fisheries Conservation Alliance

2 Tehskai (fish trap) for use in lakes. Fort St. James circa 1891.

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4 TAKL A BABINE TREMBLEUR STUART

5 Sockeye Spawner Distribution Red = Early Stuart Blue = Late Stuart Peak spawning Spawning areas Early Stuart Aug Small streams (many); Middle R., Takla Lake Late Stuart Sep Lake outlet streams Middle R., Tachie R.

6 Escapements 800, ,000 Early Stuart 400, , ,000,000 1,600,000 Late Stuart 1,200, , ,

7 Early Stuart sockeye escapement, 1938 to present

8 Driftwood River escapements 500,000 Blackwater Driftwood River Kastberg Creek Kotsine Creek Lion Creek Porter Creek 400, ,000 Massive In-river Mortality 200, ,

9 0 40,000 80, , , , , , , , ,000 40,000 60,000 80, , ,000 80, , , cycle 2005 cycle 2006 cycle 2007 cycle

10 Conclusion Status of Early and Late Stuarts Early and Late Stuart sockeye have declined since the 1990 s, in some cases severely (Driftwood River population). Populations went through similar fluctuations during the 1960 s and 1970 s, suggesting that recovery may be possible if habitat conditions remain suitable and harvest rates are kept down.

11 Why are Stuart sockeye declining?

12 Possible Explanations Overharvesting Spawning and Egg Incubation Conditions In-lake Conditions Competition with Kokanee Logging Pollution Migration Conditions and In-River Mortality

13 Early Stuart Catches Marine Catch Native In-River Catch 100% 80% 60% 40% 20% 0%

14 Late Stuart Catches Marine Catch Native In-River Catch 100% 80% 60% 40% 20% 0%

15 Spawning and Egg Incubation Egg:Fry Survival (%) Conditions Forfar Gluske Kynoch Stellako 80% 60% 40% 20% 0%

16 In-Lake Conditions: Limnology Temperature, light and turbidity profiles Nutrients - nitrogen and phosphorous Photosynthesis rate and algal biomass Zooplankton abundance and species composition

17 In-Lake Conditions: Hydroacoustics and Trawling Abundance, density and distribution of sockeye and kokanee by age class

18 Competition with Kokanee

19 Takla Lake: Juvenile sockeye are larger than juvenile kokanee juvenile kokanee juvenile sockeye Count Fork length (mm)

20 Logging DFO Study Radiation and temperatures Thermal units Escapement estimates Incubation and outmigration success Lake productivity Hydrology Channel morphology Sediment budget Streambed composition Invertebrate production Fish diets Beaver effects Bedload movement Historic channel changes Incubation habitat Predation studies, and Resident fish research

21 Spatial and Temporal Separation of Clearcuts TAKL A BABINE TREMBLEUR STUART

22 Pollution 1. Decline in Stuart/Takla Lake sockeye has occurred independently of other upriver salmon populations e.g. Stellako River sockeye. 2. Water quality improved significantly during the 1990 s, when Stuart sockeye declined. This is opposite to what you would predict if water pollution was associated with Stuart/Takla Lake sockeye declines.

23 1997 Early Stuart run failure mortality = 700,000

24 1998 Early Stuart run failure - high mortality due to temperature

25 Early Stuart Migration Window

26 Fraser River Maximum Water Temperature (Hell s Gate)

27 Fraser River Mean Water Temperature (Hell s Gate)

28 Annual average temperature over 19 days bracketing Hell s Gate position

29 Salmon temperature sensitivity

30 Hell's Gate Sawmill Hope Rosedale Thompson Confluence Seton Confluence Quesnel Confluence Stuart Confluence Kynock Creek (MOB) Tag #4; Tagged on 1-Stuart Release /14 07/16 07/18 07/20 07/22 07/24 07/26 07/28 07/30 08/01 08/03 08/05 08/07 08/09 ibutton Temperature ( C) RiverTemperature ( C) Date Temperature ( C)

31 The Fraser River in 75 years will have: Warmer winters and reduced snowpack Earlier freshet (24 days) Much later freshet in 13% of years Lower summer flows esp in tribs Temperature increase by 2 o C (higher in tribs) Higher frequency of water temp >20 o C

32 Conclusions: Early Stuart Explanation Overharvesting Egg Incubation Conditions In-lake Conditions Competition with kokanee Logging Pollution In-River Mortality Likelihood Unlikely Unlikely Unlikely Uncertain Uncertain Unlikely Highly likely

33 Salmon weir and smokehouse

34 What can be done? Maintain minimal fisheries exploitation on Early Stuarts Study of juvenile sockeye and kokanee ecology in lakes Discuss with DFO possibility of fertilizing Takla Lake in 2010 Import food fish from Babine Lake or elsewhere COSEWIC listing

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36 Stuart Sockeye Recovery Perspectives: First Nations, DFO, FSWP Strong opportunity for deep and profound collaborative approach: FN-DFO Time for action

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39 Average discharge over 19 days bracketing Hell s Gate position

40 Total Returns Commercial Marine FNs Fraser FNs Sport Escapement En-route Loss 2,000,000 1,600,000 Early Stuart 1,200, , , Commercial Marine FNs Fraser FNs Sport Escapement En-route Loss 6,000,000 5,000,000 Late Stuart 4,000,000 3,000,000 2,000,000 1,000,

41 Migration Conditions and In- River Mortality Shift in Early Stuart arrival date by 5 days warmer SST?

42 Wild Salmon Policy At Present: 6 Conservation units Risk of Extirpation High Lower Benchmark Low Upper Benchmark Low High Spawner Abundance COSEWIC Listing?