ARROW LAKES RESERVOIR ANGLER CREEL SURVEY 2010-2012 Steve Arndt, M.Sc. Ministry of ...

60 Pages·2014·5.61 MB·English

ARROW LAKES RESERVOIR ANGLER CREEL
SURVEY 2010-2012

Steve Arndt, M.Sc.

Ministry of Forests, Lands and Natural Resource Operations
Fish & Wildlife Compensation Program – Section
401-333 Victoria St, Nelson, BC

Prepared with financial support of:

Fish and Wildlife Compensation Program on behalf of its program partners BC Hydro, the
Province of BC, Fisheries and Oceans Canada, First Nations and the public
&
Arrow Lakes Power Corporation

April 2014
Arrow Lakes Creel Summary 2010 - 2012

Executive Summary
The Fish and Wildlife Compensation Program (FWCP) annually funds a nutrient restoration project
(started in 1999) and Hill Creek Spawning Channel (started 1981) on Arrow Lakes Reservoir (ALR) as
compensation for the footprint impacts of BC Hydro’s Hugh Keenleyside Dam at the outlet, and Mica and
Revelstoke dams and reservoirs upstream. Nutrient program funding is also contributed by Columbia
Power Corporation as compensation for entrainment at the Arrow Lakes Generating Station.
Access point angler surveys have been conducted at selected ALR locations as early as 1976 to monitor
the effects of BC Hydro dams and fishery compensation efforts. They provide a valuable long term index
of fishing effort and harvest starting from dam construction through to 14 years after the beginning of the
nutrient program. They also provide trend data for Rainbow Trout and Bull Trout populations, which have
not been monitored by other methods until recently.

Anglers were interviewed at three primary access locations (Shelter Bay, Nakusp, Castlegar) on three
weekdays and two weekend/holidays per month (randomly-selected within day-type) throughout each
year. For estimation of whole reservoir effort and catch from 2010 to 2012, estimates from the three
access locations were expanded using monthly correction factors derived from the ratio of access-sampled
boats to total boats counted during airplane flights made over the whole reservoir. To assess longer term
trends in relation to FWCP compensation initiatives, estimates specific to the three sampled locations were
used, with pre-nutrient years (1987-1998) compared to the 14 years of the nutrient program. Trends in
relative condition factor (K ) were also examined to evaluate feeding conditions for apex predators
n
feeding primarily on Kokanee.

Total annual effort from 2010 to 2012 ranged from 15,500 to 18,600 angler days. Annual catch of the four
main species (including released fish) ranged from 12,400 to 20,200 with a weight harvest of 8 to 10
tonnes. Annual expenditures wholly attributable to the fishery are about $1 million based on daily values
from a federal angler survey, or $4 million including major purchases partly attributable to the fishery.
Residents of British Columbia comprised more than 90% of anglers. Angling effort out of the Castlegar
access has declined substantially since the 1990s due to a substantial decline in the Kokanee fishery.
Nakusp effort, which targets mainly Bull Trout and large Rainbow Trout, increased to well above pre-
nutrient levels between 2001 and 2005. Since then it has returned to levels similar to 1987-1998. Shelter
Bay effort has increased gradually over the last decade and slightly exceeded Nakusp in 2012.

Annual Bull trout catch from 2010-2012 was about 4,000 fish/year. About half of these were retained for
harvests of 4,200 - 4,600 kg/year. Catch rate (CPUE) ranged from 0.06 - 0.08 fish/h. Catch of bull trout
increased sharply in 2001, three years after the beginning of the nutrient program, and remained at a
higher level until 2005. Since then, catch has declined to levels similar to pre-nutrient years. Rainbow
trout catch from 2010-2012 ranged from 4,400 – 7,500 fish/year; about two thirds of which were retained
for harvests of 2,700 -3,900 kg/year; CPUE ranged from 0.06 - 0.10. Harvest of piscivorous rainbow trout
≥ 50 cm was ~500 fish in 2012. This was the third highest on record since the nutrient program began,
although the proportion of fish > 4.5 kg was not as high as during 2002-2005. No hatchery stocked
(clipped) Rainbow Trout were detected in the samples. Burbot comprise a much smaller, but relatively
stable, fishery with catch ranging from 500 - 750 fish/year and harvest 600-1,000 kg/year.

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Arrow Lakes Creel Summary 2010 - 2012

Kokanee harvest from 2010-2012 ranged from 2,200 – 5,700 fish/year (300 - 800 kg/year) with average
CPUE of 0.3 – 0.5 fish/h. The estimate for 2012 was about a ninth of 1990-1996 levels, the lowest on
record. The decreased harvest has been accompanied by declines in kokanee-directed effort. Both
Kokanee effort and harvest since 1998 are positively related to mean size of retained kokanee, which has
declined in recent years.

The average condition factor (K ) of Bull Trout from 2010-2012 was about ten percent above the pre-
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nutrient benchmark. This is a slight increase from 2006-2008 but below a peak from 2001-2004.
Condition of piscivorous Rainbow Trout for the last seven years has remained at levels intermediate
between the pre-nutrient level and a peak period from 2002-2005. These trends suggest feeding conditions
for apex predators from 2010-2012 were slightly better than the average of pre-nutrient years, but below
results achieved earlier in the nutrient period.

Increases in piscivore catch rate, harvest, size and condition factor suggest a strong positive response to
nutrient additions reaching to the upper trophic levels during the first seven years of the program, at least
in the upper basin of the reservoir. Declines in more recent years suggest that nutrient transfer efficiency
has been reduced, for reasons that are as yet unclear. The recent decline in Kokanee angling appears to be
related at least partially to the size reduction that accompanies increased density. Reductions in kokanee
catch limits (from 15 to 5 since 1995) may also be a factor for this species.

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Arrow Lakes Creel Summary 2010 - 2012

Acknowledgements
Thanks to the anglers who contributed information to the surveys, and creel clerks Glen and Gail
Olson in Nakusp, Deb and Lorne Imeson and staff at Scotties Marina, and Brian Barney and
Darlene Riehl at Shelter Bay for their efforts in collecting field data. Beth Woodbridge and
Valerie Evans entered data, and Sarah Stephenson assisted with converting the database to
Access 2007. Dr. Carl Schwarz, Simon Fraser University, kindly provided analyses for angler
effort, catch and harvest estimates.

The report was improved by review comments from Joe De Gisi and Tyler Weir of the Ministry
of Forests, Lands, and Natural Resource Operations, and from Llewellyn Matthews of Arrow
Lakes Power Corporation.

This work was funded by: (1) the Fish and Wildlife Compensation Program on behalf of its
program partners BC Hydro, the Province of B.C., First Nations and the public, who work
together to conserve and enhance fish and wildlife impacted by the construction of BC Hydro
dams; and (2) Arrow Lakes Power Corporation. Arrow Lakes Power Corporation is jointly
owned, on a 50/50 basis, by Columbia Power Corporation and CBT Arrow Lakes Power
Development Corporation (an indirect subsidiary of Columbia Basin Trust).

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Arrow Lakes Creel Summary 2010 - 2012

Table of Contents
1.0 INTRODUCTION ................................................................................................................................. 1
2.0 METHODS ............................................................................................................................................ 2
2.1 Field Sampling ................................................................................................................................... 2
2.2 Analyses .............................................................................................................................................. 4
2.2.1 Effort and Catch Estimation ......................................................................................................... 4
2.2.2 Catch per Unit Effort .................................................................................................................... 5
2.2.3 Condition Factor of Piscivorous Rainbow Trout and Bull Trout ................................................. 6
3.0 RESULTS AND DISCUSSION ............................................................................................................ 6
3.1 Overflight Boat Counts and Percentage of Parties Interviewed ................................................... 7
3.2 Fishery Overview ............................................................................................................................... 8
3.3 Angling Effort and Potential Expenditures .................................................................................. 11
3.3 Harvest, Size and Catch Trends ..................................................................................................... 13
3.3.1 Bull Trout ................................................................................................................................... 13
3.3.2 Rainbow Trout ............................................................................................................................ 16
3.3.3 Kokanee ...................................................................................................................................... 21
3.3.4 Burbot ......................................................................................................................................... 25
3.4 Condition Factor of Apex Predators.............................................................................................. 28
3.5 Hatchery Contribution to the Fishery ........................................................................................... 29
4.0 CONCLUSIONS AND RECOMMENDATIONS ............................................................................ 30
4.1 Fishery Trends ................................................................................................................................. 30
4.2 Survey Methods ............................................................................................................................... 31
4.3 Related Population Assessment ...................................................................................................... 32
5.0 REFERENCES .................................................................................................................................... 33
6.0 APPENDICES ..................................................................................................................................... 36
1. Angler residence composition on Arrow Lakes Reservoir from 1976 to 2009.
2. Arrow Lakes creel survey annual estimates using a common monthly correction factor from
2003 to 2012.
3. Size statistics for Bull trout, Rainbow trout, Kokanee and Burbot in the Arrow Lakes
Reservoir creel survey from 1998 to 2012.
4. Locations of fishing boats on Arrow Lakes Reservoir for 48 flights made in 2011 and 2012.

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Arrow Lakes Creel Summary 2010 - 2012

List of Tables and Figures
Table 1. Spatial and temporal strata for the Arrow Lakes Reservoir creel survey from 2010 to 2012. ........ 2
Table 2. Number of anglers sampled and residence category percentages for the Arrow Lakes Reservoir
creel survey from 2010 to 2012................................................................................................................ 7
Table 3. Percentage of fishing boats (average, minimum and maximum) interviewed at three sampled
access locations in Arrow Lakes Reservoir that were active during overflight counts of fishing boats in
2011-2012. ............................................................................................................................................... 7
Table 4. Percentage of sampled angler-days and rod-hours by species sought category based on sampling
at three access locations in Arrow Lakes Reservoir from 2010 to 2012 .................................................. 8
Table 5. Three measures of estimated angling effort (±95% confidence limits) for Arrow Lakes Reservoir
from 2010 to 2012. ................................................................................................................................. 12
Table 6. Bull trout angler catch, harvest ( 95% confidence limits) and catch per unit effort in Arrow
Lakes Reservoir from 2010 to 2012. ...................................................................................................... 13
Table 7. Rainbow trout angler catch and harvest ( 95% confidence limits) statistics for Arrow Lakes
Reservoir from 2010 to 2012. ................................................................................................................ 17
Table 8. Kokanee catch and harvest ( 95% confidence limits) statistics for Arrow Lakes Reservoir from
2010 to 2012. .......................................................................................................................................... 22
Table 9. Burbot catch and harvest ( 95% confidence limits) statistics for Arrow Lakes Reservoir from
2010 to 2012 ........................................................................................................................................... 25

Fig. 1. Map of Arrow Lakes Reservoir showing sampled access locations at Shelter Bay, Nakusp, and near
Castlegar ................................................................................................................................................... 3
Fig. 2. Percentage of sampled effort by species-sought category (three access locations pooled) in Arrow
Lakes Reservoir from 1998 to 2012 ......................................................................................................... 9
Fig. 3. Catch of harvested and released fish by month and species at three access locations on Arrow
Lakes Reservoir in 2009 ......................................................................................................................... 10
Fig. 4. Number of angler-days by month estimated for three access locations in Arrow Lakes Reservoir in
2012. ....................................................................................................................................................... 11
Fig. 5. Trends in annual angler days at three access locations on Arrow Lakes Reservoir from 1987 to
2012. ....................................................................................................................................................... 12
Fig. 6. Trends in (a) harvested number (b) targeted rod-hours, and (c) catch rate of Bull Trout from three
access locations in Arrow Lakes Reservoir from 1987 – 2012. ............................................................. 14
Fig. 7. Length frequency distributions of bull trout angled from Arrow Lakes Reservoir from 2010 to
2012. ....................................................................................................................................................... 15
Fig. 8. Percentage of weighed Bull Trout by size category at three sampled locations from 1998 to 2012.
................................................................................................................................................................ 16
Fig. 9. Trends in (a) harvested number, (b) targeted rod-hours, and (c) catch rate of Rainbow Trout from
three locations in Arrow Lakes Reservoir from 1987 – 2012. ............................................................... 18
Fig. 10. Length frequency distributions of rainbow trout angled from Arrow Lakes Reservoir from 2010 to
2012. ....................................................................................................................................................... 19
Fig. 11. Number of rainbow trout ≥ 50 cm sampled at three access locations during the Arrow Lakes creel
survey from 1998 to 2012. ..................................................................................................................... 20
Fig. 12. Percentage of weighed Rainbow Trout by size category in Arrow Lakes Reservoir from 1998 to
2012. ....................................................................................................................................................... 21
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Arrow Lakes Creel Summary 2010 - 2012

Fig. 13. Trends in (a) harvested number, (b) targeted rod-hours, and (c) catch rate of kokanee from three
access locations in Arrow Lakes Reservoir from 1987 – 2012. ............................................................. 23
Fig. 14. Length frequency distributions of kokanee angled from Arrow Lakes Reservoir from 2010 to
2012. ....................................................................................................................................................... 24
Fig. 15. Relationship between the amount of kokanee-directed effort (Castlegar, Nakusp and Shelter Bay
combined) and mean length of harvested kokanee in Arrow Lakes Reservoir from 1998 to 2012. ...... 25
Fig. 16. Trends in the (a) number of fish kept, (b) directed rod-hours, and (c) catch rate for Burbot anglers
launching from Nakusp in Arrow Lakes Reservoir from 1987-2012. .................................................... 26
Fig. 17. Length frequency distributions for Burbot angled from Arrow Lakes Reservoir from 2010 to
2012. ....................................................................................................................................................... 27
Fig. 18. Mean annual condition factor (K ) relative to the average pre-nutrient weight (K =1) for all bull
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trout (± 95% confidence limits), and for bull trout over 60 cm in Arrow Lakes Reservoir from 1991 to
2012. ....................................................................................................................................................... 28
Fig. 19. Mean annual condition factor (K ) relative to the average pre-nutrient weight (K =1) for all
n n
piscivorous Rainbow Trout (± 95% confidence limits) in Arrow Lakes Reservoir from 1994 to 2012. 29

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Arrow Lakes Creel Summary 2010 - 2012

1.0 INTRODUCTION
Arrow Lakes Reservoir (ALR) is located in the West Kootenay Region of British Columbia,
extending southward from Revelstoke for a distance of about 200 kilometers to H.L. Keenleyside
Dam near Castlegar. It has a total surface area (upper and lower basins) of 46,450 ha at full pool
(Pieters et al. 2003), and is affected by Keeleyside Dam and Arrow Lakes Generating Station at
the outlet, and two facilities upstream (Mica and Revelstoke). Water management of the reservoir
is strongly influenced by requirements of the Columbia River Treaty. Impacts to fish populations
include the loss of stream spawning and juvenile rearing habitats in the lower reaches of Arrow
tributaries due to inundation by Keenleyside Dam and blocked access to streams above
Revelstoke Dam; upstream dams also caused changes in nutrient levels, water clarity and primary
productivity in the reservoir limnetic habitat (Matzinger et al. 2007, Moody et al. 2007, Hagen
2008, Arndt 2009a, 2009b). The fish community in ALR includes 24 species (McPhail and
Carveth 1992), with the recreational fishery targeting four of these: Kokanee Oncorhynchus
nerka, Bull Trout Salvelinus confluentus, Rainbow Trout Oncorhynchus mykiss, and Burbot Lota
lota. Rainbow Trout in ALR occur in two different ecotypes, a slower growing (mostly
insectivorous) type reaching a maximum length of about 45 cm, and a piscivorous type that can
exceed 90 cm (Arndt 2004b).
The Fish and Wildlife Compensation Program (FWCP) currently funds two large-scale
compensation projects in ALR. Hill Creek Spawning Channel commenced fry production in
1981, aiming to compensate for lost Kokanee and Rainbow Trout spawning habitat upstream of
Revelstoke Dam. It also provides juvenile rearing habitat for both ecotypes of Rainbow Trout.
The ALR Nutrient Restoration Project began in 1999 to address nutrient losses related to the
upstream dams. Limiting nutrients (phosphorus and nitrogen) are dispensed into the upper basin
during the growing season with the goal of increasing reservoir primary production (Pieters et al.
2003, Schindler et al. 2006). Increased primary production is expected to translate into higher
Kokanee production and improved growth and survival of Bull Trout and piscivorous Rainbow
Trout in the reservoir. Productive fish stocks provide angling opportunities and economic benefits
to local communities and the province.
A fish hatchery, operated at the Hill Creek site for Bull Trout and Rainbow Trout, was
discontinued after 2000 due to poor survival of released fish (Arndt 2004a). However, small
releases of piscivorous Rainbow Trout were made from 1995 to 2002 by Selkirk College, and
from 2005 to 2010 the Freshwater Fisheries Society of BC released triploid Rainbow Trout
yearlings on an experimental basis. Fish from the later releases could be contributing to the
fishery during the 2010-2012 survey.
Angler surveys have been conducted annually at selected access locations in ALR since the
1970s to monitor the effects of the dams on fish populations and recreational fisheries, and the
success of compensation efforts. These surveys provide a valuable index of angling effort and
harvest trends, and the only long-term dataset on Bull Trout and Rainbow Trout in the reservoir.
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Arrow Lakes Creel Summary 2010 - 2012

Previous surveys are summarized in Sebastian et al. (2000), Arndt (2002a, 2004a), and Arndt and
Schwarz (2011).
This report provides angler effort, catch, and harvest estimates, and summarizes biological
attributes of the harvest (size structure, piscivore condition factor) for surveys from 2010 to 2012.
Results for these years are compared as far back as 1987 using trend graphs. The creel survey is a
key component of the ongoing evaluation of the nutrient and spawning channel programs funded
by FWCP. Questions addressed with these data include:
 What are the recreational, food, and economic values of the fishery?
 How does the 2010-2012 fishery compare to previous years, particularly the years prior to
the beginning of the nutrient program?
 Does the nutrient program benefit the top trophic levels in the reservoir?
 Have feeding conditions for apex predators improved since the nutrient program began?
 Have stocked Rainbow Trout and spawning channel Kokanee benefited the fishery?

2.0 METHODS
Field and analysis methods for the study period were very similar to those described in Arndt and
Schwarz (2011); additional details are provided in that report. One notable difference for 2010 to
2012 is a reduced period of sampling for 2010 (January to March) and 2011 (April to December),
because the survey was not funded for the 2010/11 fiscal year.
2.1 Field Sampling
Anglers were interviewed by creel clerks at three primary access locations (Shelter Bay, Nakusp,
Castlegar) for five days each month from January to March 2010, April to December 2011, and
January to December 2012 (Table 1; Fig. 1). Three weekdays (WD) and two weekend/holidays
(WE) were sampled for each month, providing coverage of about a sixth of the total days in a
year, and slightly less than a quarter of the weekend/holidays. Sampling was randomized within
the day types and sampled days were the same at all three access locations. Weekday samples
included one randomly-selected Monday in each month to be consistent with past surveys,
however all weekdays were combined for analyses (Arndt 2002).

Table 1. Spatial and temporal strata for the Arrow Lakes Reservoir creel survey from 2010 to 2012.
Access Location Description Sampling Frequency
Shelter Bay Shelter Bay Provincial Park boat ramp (shifts to 5 days per month
nearby ferry ramp if park is inaccessible due to snow) (3 weekdays and 2
Nakusp Government ramp in the Town of Nakusp weekend/holidays)
Castlegar Scotties Marina and Syringa Provincial Park public
boat launches; both locations are near the
downstream end of the reservoir

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Arrow Lakes Creel Summary 2010 - 2012

Fig. 1. Map of Arrow Lakes Reservoir showing sampled access locations at Shelter
Bay, Nakusp, and near Castlegar.

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