j.e. bisset, s.k.a. arndt, r.s. cope · 2013. 5. 9. · columbia lake burbot population estimate...

COLUMBIA LAKE BURBOT POPULATIONESTIMATE PROGRAM, CANAL FLATS, BC

PREPARED BY

J.E. Bisset, S.K.A. Arndt, R.S. Cope

FORColumbia-Kootenay Fisheries Renewal Partnership

In Partnership with

June 2002

COLUMBIA BASINFISH & WILDLIFECOMPENSATION

PROGRAM

www.cbfishwildlife.org

Columbia Lake

Burbot Population Estimate Program, Canal Flats, B.C.

Prepared for:

Columbia-Kootenay Fisheries Renewal Partnership

7468 Mission Road Cranbrook, BC

V1C 7E5

June 2002

Prepared by: Westslope Fisheries 517 13th Avenue South Cranbrook, B.C. V1C 2W5 (250) 426-8381

AND

Columbia Basin Fish & Wildlife Compensation Program 103-333 Victoria Street Nelson, BC V1L 4K3 (250) 352-6178

Columbia Lake Burbot Monitoring Program Westslope Fisheries

June 2002 •••• ii

Executive Summary

Columbia Lake burbot have been the subject of a number of investigations since 1996. These

have included six years of spawner enumeration at a tributary, tracking of post-spawning

movement, surveys of juvenile abundance and habitat use, and estimates of angler harvest.

This study was designed to provide a population estimate of adult burbot in the lake to

complement the earlier studies. In addition, information was obtained on the size distribution of

lake-captured fish, and the depth and habitats used.

The study took advantage of the fact that 995 burbot had been tagged as part of spawner

enumeration early in 2001; these fish were used as the first phase of a mark-recapture

population estimate. Sixteen cod traps were deployed at locations across Columbia Lake and

the upper Columbia River from May 30 to June 7, and October 2 to October 11, 2001. The sites

for the location of cod traps were chosen based on previous radiotelemetry surveys and

suspected concentrations of prey in the autumn. These traps have been used very successfully

to capture burbot in other lakes of the Kootenay Region.

A total of 266 trap-days of effort were expended during the spring and autumn capture periods,

resulting in a catch of 57 burbot of which three had been tagged in previous studies. There were

zero recaptures for tags applied during this study. These catch rates were approximately one

tenth of that expected based on other lakes, and resulted in a population estimate with wide

95% confidence limits (11,194 ± 9,557) that restrict its application to research and management

questions. However, new information was obtained on aspects of life history and habitat use.

Size distribution of burbot in the lake changed substantially between the spring and autumn

periods, suggesting that a large number of adult burbot may have been absent from the lake

during spring sampling. This contradicts an earlier radiotelemetry study and may indicate that

post-spawning movement patterns differ from year to year. Also, when spring and fall size

distributions in the lake are combined, it appears that the 1997 cohort was more abundant than

the 1999 cohort. This contrasts with the relative abundance of these two cohorts in the tributary

spawners of 2001.

Depths occupied by lake-captured burbot were different from those determined in an earlier

study that suggested a length of 39 cm as the size at which burbot moved from shoreline to

deeper habitats. In this study, burbot less than 30 cm were captured at depths up to 6 m, and

burbot over 50 cm were captured as shallow as 1 m.


June 2002 •••• iii

If future population estimates are contemplated, consideration should be given to the following

recommendations:

• Assume relatively low catch rates and plan for a longer, intensive collection period;

• Consider that autumn sampling coinciding with kokanee spawning migration (and

spawning locations) may be more productive than spring sampling;

• Use fresh kokanee bait to improve capture rates if available; and

• Consider expanding the study area beyond Columbia Lake (e.g., Windermere Lake,

Moyie Lake).


June 2002 •••• iv

Acknowledgements

Funding for the “Columbia Lake Burbot Population Estimate” was provided by Columbia-

Kootenay Fisheries Renewal Partnership, Fisheries Renewal British Columbia (FsRBC) and

Columbia Basin Trust (CBT), and administered by the Columbia Basin Fish and Wildlife

Compensation Program (CBFWCP). CBFWCP also provided in kind support of the project for

planning and design of the study, aspects of fieldwork, and reporting. The CBFWCP is a joint

initiative between BC Hydro and the Government of British Columbia to conserve and enhance

fish and wildlife populations in the Canadian portion of the Columbia River basin.

The authors wish to acknowledge all the individuals that have contributed to bringing this project

to a successful conclusion. Their contributions and on-going efforts are greatly appreciated.

Marty Williams, Pat Nicholas (St. Mary’s Band), Glen Smith, (Westslope Fisheries), Kenton

Andreashuk, Chris Beers (CKFRP), Harald Manson, Beth Woodbridge (CBFWCP), and Colin

Spence (Ministry of Water, Land, and Air Protection) provided technical support. Dr. Carl

Schwarz (Cooperative Resource Management Institute, Simon Fraser University) provided

advice on the sampling design. Cod traps were loaned by the Ministry of Water, Land, and Air

Protection.

Suggested citation for this report:

Bisset, J.E., Arndt, S.K.A. and R.S. Cope 2002. Columbia Lake Burbot Population Estimate Program, Canal Flats B.C. Report prepared for Columbia-Kootenay Fisheries Renewal Partnership, Cranbrook, B.C. Prepared by Westslope Fisheries, Cranbrook, B.C. and Columbia Basin Fish and Wildlife Compensation Program, Nelson, B.C. 21 pp. + 2 app.


June 2002 ••••v

Table of Contents

EXECUTIVE SUMMARY ........................................................................................................... II

ACKNOWLEDGEMENTS......................................................................................................... IV

TABLE OF CONTENTS............................................................................................................. V

LIST OF TABLES ..................................................................................................................... VI

LIST OF FIGURES.................................................................................................................... VI

1 INTRODUCTION............................................................................................................... 1

1.1 Background .................................................................................................................... 1

1.2 Project Rationale ............................................................................................................ 2

1.3 Study Area...................................................................................................................... 3

2 METHODS ........................................................................................................................ 5

2.1 Sampling Design ............................................................................................................ 5

2.2 Spring Sampling ............................................................................................................. 7

2.3 Autumn Sampling ......................................................................................................... 11

3 RESULTS ....................................................................................................................... 14

3.1 Water Temperature....................................................................................................... 14

3.2 Fishing Effort and Catch ............................................................................................... 15


June 2002 ••••vi

3.3 Burbot Size, Abundance, and In-lake Distribution ......................................................... 19

4 DISCUSSION.................................................................................................................. 22

5 LITERATURE CITED ...................................................................................................... 26

APPENDIX A FIELD DATA FORMS - COD TRAP SET SUMMARIES FROM THE COLUMBIA LAKE BURBOT POPULATION ASSESSMENT, 2002

APPENDIX B FIELD DATA FORMS – INDIVIDUAL FISH CAPTURE DATA FROM THE COLUMBIA LAKE BURBOT POPULATION ASSESSMENT, 2002

List of Tables

Table 1. Summary of geographic information for Columbia Lake.............................................. 3 Table 2. Known species composition in Columbia Lake. .......................................................... 5 Table 3. Summary of data on previously tagged burbot captured during trapping in Columbia

Lake and River in 2001. ........................................................................................... 19

List of Figures

Figure 1. Location of Columbia Lake in relation to communities of Canal Flats and Fairmont Hot Springs, BC. Source: BC Ministry of Forests, Forest Service Recreation Map, Invermere Forest District. .......................................................................................... 4

Figure 2. Typical baited cod trap used in Columbia Lake burbot population study being deployed. .................................................................................................................. 8

Figure 3. Autumn sampling locations on the south end of Columbia Lake near Canal Flats, BC. ............................................................................................................................. 9

Figure 4. Autumn sampling locations on the north end of Columbia Lake and the upper Columbia River near Fairmont Hot Springs, BC. ...................................................... 10

Figure 5. Anesthetized burbot prior to checking for tags, and processing................................ 11 Figure 6. Burbot being checked for tags/marks prior to being measured. ................................ 12 Figure 7. Pit tag reader being used to check adult burbot for previous tags, Columbia Lake. .. 12 Figure 8. Pit tag being implanted in left cheek of adult burbot, Columbia Lake. ....................... 13


June 2002 ••••vii

Figure 9. Adult burbot in recovery cooler prior to release, Columbia Lake............................... 13 Figure 10. Adult burbot released into Columbia Lake following Pit tagging procedure............... 14 Figure 11. Mean daily water temperatures recorded in trap T-12, Columbia Lake May 29 to June

7, 2001..................................................................................................................... 15 Figure 12. Columbia River trap site R-1, October 2001............................................................. 16 Figure 13. Columbia River trap site R-2, October 2001............................................................. 17 Figure 14. Columbia River site R-3, October 2001. ................................................................... 17 Figure 15. Typical cod trap location, Columbia Lake, October 2001.......................................... 18 Figure 16. Typical cod trap location, Columbia Lake, October 2001.......................................... 18 Figure 17. Northern pike minnow regurgitating kokanee following removal from a cod trap,

Columbia Lake, October 2001.................................................................................. 19 Figure 18. Length-frequency distributions for spring and autumn cod trap sampling in Columbia

Lake and River, 2001. .............................................................................................. 20 Figure 19. Burbot catch by depth, in relation to effort, for spring and fall trapping on Columbia

Lake in 2001. ........................................................................................................... 21 Figure 20. Length-frequency distributions of burbot at the spawning tributary (January –

February) and in Columbia Lake and River (spring and fall sampling combined) in 2001. Dominant cohorts in the distribution peaks are based on otolith ages of tributary fish (Arndt 2002). Growth occurred between the spawning and the lake sampling. .. 24

Figure 21. Length of individual burbot and their depth of capture in cod-traps in Columbia Lake in spring and autumn 2001. During autumn, most trapping was done at depths less than 3 m. The dotted line shows the maximum length of shoreline residence found during backpack electrofishing in July (Taylor 2001). ............................................... 25


June 2002 ••••1

1 Introduction

1.1 Background

Burbot Lota lota (also commonly referred to as ling-cod, or ling) are the only freshwater

members of the cod family. They are generally nocturnal and feed primarily on other fish

species. Burbot spawn in winter from January to March. Spawning occurs at night as

individuals aggregate in spawning “balls” over suitable (sand and gravel) substrates (McPhail

and Paragamian 2000). Burbot have a wide, Holarctic distribution (McPhail and Paragamian

2000), occupying suitable habitats north of 40ºN latitude (Scott and Crossman 1973). The

Kootenay Region once supported large fisheries for burbot including popular angling locations

such as Windermere and Columbia Lakes in the upper Columbia system, the Spillimacheen

River, Moyie Lake, and Kootenay Lake at Balfour (Hutchinson 1996; Prince 2001).

Burbot played an important role in the early settlement of the east and west Kootenays and

provided important food resources for First Nations and early settlers (Prince 2001). Adult

burbot were typically harvested at night through the ice during January and February, as large

numbers of individuals congregated near the spawning grounds. Typical capture methods

included setlines, spears, and angling. Some of the largest burbot on record from British

Columbia have been reported from the Kootenay Region, including a 15.44 kg burbot from

Windermere Lake in 1923 (McPhail and Paragamian 2000). Large catches were reported in

fishing derbies in some parts of the region. Creel data and angler surveys have since shown

dramatic declines in the number and size of burbot captured in some locations (Prince 2001),

particularly Kootenay Lake and the Kootenay River.

A number of studies, funded by the Columbia Basin Fish & Wildlife Compensation Program

(CBFWCP), have recently been completed on the burbot of Columbia Lake near Canal Flats,

B.C. These have included: a study of early life history characteristics (Taylor and McPhail

2000; Taylor 2001), six years of adult spawner enumeration at a tributary spawning site (Arndt

and Hutchinson 2000; Arndt 2000; Arndt 2002), an 18 month study of post-spawning movement

patterns of adult burbot (Arndt 2001a), and 5 years of angler harvest assessment (Arndt 2001b).

The present study was designed with intent to develop the first burbot population estimate for

any lake in the Kootenay Region. Specific study objectives were to:

• Obtain a defensible estimate of the total number of adult burbot in Columbia Lake;


June 2002 ••••2

• Compare the size distribution of lake-captured burbot to tributary spawners the previous

winter; and

• Collect basic habitat use information for spring and autumn.

1.2 Project Rationale

Burbot have become a species of concern in the Kootenay Region due to declines in certain

areas and the relative lack of biological information about the species. The research at

Columbia Lake was initiated due to concerns about local development proposals, as well as

region-wide interest. So far it has resulted in two refereed publications (Arndt and Hutchinson

2000; Taylor and McPhail 2000) and several technical reports that have contributed to the

understanding of burbot biology in western North America.

The Columbia Lake studies have shown large fluctuations in juvenile abundance and tributary

spawner numbers, as well as large fluctuations in angler harvest; however, several unanswered

questions hinder the interpretation of the data. For example:

1) What proportion of Columbia Lake adult burbot spawn at the tributary (It is known that there

are also spawning locations in the lake itself)?

2) What proportion of burbot switch spawning sites or skip spawning in some years?

3) Are tributary spawner counts a valid index of adult burbot abundance in the lake (based on

the above two questions)?

4) What proportion of the total population is being harvested?

5) What was the survival of cohorts that were monitored at the juvenile stage?

A population estimate of adult burbot in Columbia Lake would help answer the above questions,

and allow fluctuations in tributary spawner numbers and harvest to be put into better ecological

and management perspective.

In addition, approximately 1000 burbot had already been marked with passive integrated

transponder (PIT) tags as part of the sixth and last spawner count in the tributary in late winter

of 2001 (Arndt 2002). Previous radiotelemetry work (1997-1998) indicated that these burbot

should be well distributed throughout the lake by spring 2001 (Arndt 2001a). Therefore they

could serve as the first part of a two-stage mark-recapture population estimate (Begon 1979). A

second phase of capture data in the lake was required to provide a ratio of marked/unmarked

fish for a population estimate.


June 2002 ••••3

In summary, the rationale for the population estimate was as follows:

1) It was considered to be a very valuable addition to other long-term studies in Columbia

Lake, and a key component for understanding the population dynamics of burbot in the lake.

2) It would take advantage of burbot already marked as part of another study, resulting in

substantial savings in field effort and cost.

1.3 Study Area

Columbia Lake is a 2509.7 ha waterbody (FISS 2002) located in the Rocky Mountain Trench,

between the Purcell mountains to the west and the Kootenay Ranges of the Rockies to the east,

between the communities of Canal Flats to the south, and Fairmont Hot Springs to the north

(Table 1). Columbia Lake has a mean depth of 2.9m and a maximum depth of 6.0 m. Columbia

Lake and its major tributaries (Marion Creek, Hardie Creek, Dutch Creek, and Warspite Creek)

form the headwaters of the Columbia River, which drains to the north out of Columbia Lake

(Figure 1). Surface total dissolved solids (TDS) are in the order of 230 ppm and the lake is

slightly alkaline with a pH of 8.1 (FISS 2002). Table 2 lists the known fish species in Columbia

Lake (FISS 2002).

Table 1. Summary of geographic information for Columbia Lake.

Geographic Information

Surface Area 2,509.7 ha

Approximate Distance to Nearest Town 1 km To Canal Flats, BC

MoELP Region 4

MoELP Management Unit 4-25

FOC District Interior South East (#30)

Ministry of Forests Region Nelson

Ministry of Forests District Invermere

NTS Map Reference 082.J05

Water body Identifier 00782COLR

Watershed Code 300


June 2002 ••••4

Figure 1. Location of Columbia Lake in relation to communities of Canal Flats and Fairmont Hot

Springs, BC. Source: BC Ministry of Forests, Forest Service Recreation Map, Invermere Forest District.


June 2002 ••••5

Table 2. Known species composition in Columbia Lake.

Species Code Scientific Name

Kokanee KO Oncorhynchus nerka

Rainbow Trout RB O. mykiss

Westslope Cutthroat Trout WCT O. clarki

Bull Trout BT Salvelinus confluentus

Mountain Whitefish MW Prosopium williamsoni

Burbot BB Lota lota

Largescale Sucker CSU Catostomus macrocheilus

Longnose Sucker LSU C. catostomus

Northern Pike minnow NSC Ptycheilus oregonensis

Peamouth Chub PCC Mylocheilus caurinus

Redside Shiner RSC Richardsonius balteatus

Torrent Sculpin CRH Cottus rhotheus

Pumpkinseed PMB Lepomis gibbosus

2 Methods

2.1 Sampling Design

The population of interest was adult burbot in Columbia Lake. In February-March of 2001, 995

adult burbot (≥ 300 mm total length) were marked with PIT tags in a south end tributary during

monitoring of the spawning run. An earlier radio-telemetry study of post-spawning movement

(1997-1998; 26 fish tracked) showed an initial northward movement followed by southward

movement of some individuals so that fish were well distributed throughout the lake by May 12

(Arndt 2001a). Fish continued to move in the lake during June. Timing of the initial sampling

was scheduled from late May to early June to coincide with the period when radiotelemetry

studies indicated that fish were making substantial movements throughout the whole lake.

Bernard et al. (1993) also found catch rates to be highest during the spring for Alaskan lakes.

A rough approximation of the expected population number is needed to determine the amount

of sampling required to obtain an estimate with a useful level of precision (Everhart and Young

1981). Based on juvenile densities and tributary spawner numbers from 1996-2001, it was

expected that the adult burbot population in Columbia Lake should be in the range of 2,000 to

10,000 fish. Using the number of marked fish (995) and the expected range above, it was


June 2002 ••••6

determined that approximately 500 fish should be sampled in the lake for a population estimate

with 95% confidence limits of +/- 20% of the estimate (Carl Schwarz, Simon Fraser University,

personal communication).

Cod traps (described in Spence 2000) baited with dead kokanee (frozen from the previous fall)

were used as the main capture method for the study. The traps were borrowed from the Ministry

of Water, Air, and Land Protection (MWALP). These traps are used by MWALP to capture

burbot in other Kootenay Region lakes, and they typically have capture rates of up to 3 or 4 fish

per 48 h set (Colin Spence, personal communication) using the same bait at the same time of

year. Sixteen cod traps were available, with initial funding for up to 15 days of sampling, to

obtain a capture target of approximately 500 fish (16 traps X 2 fish/24 h trap set X 15 days =

480 fish).

The study was designed to allow use of two methods of population estimation. The first would

be a simple Petersen estimate using the ratio of tributary-marked fish in the lake catch (Begon

1979). The second method would be based on successive days of mark and recapture in the

lake trapping phase. Use of more than one estimation method with differing assumptions is

advantageous because if the two estimates disagree, it may help indicate invalid assumptions; if

the estimates agree, confidence in the estimates is increased.

Spring trap placement was based loosely on an Alaskan study (Bernard et al. 1993). Columbia

Lake is approximately 16 km long by 1.5 km wide. We used 16 transects, running east-west

across the lake, spaced about 1 km apart from the north to south end. Transects were

numbered from T1 to T16 starting from the north end of the lake.1

Each transect had 15 sites 100 m apart. The starting site for each transect was chosen from a

random number table. Traps were moved one site east every day, so that during the course of

15 days of sampling, all sites between the west and east side of the lake would be sampled.

Moving traps each day has the advantage of averaging out incomplete mixing of tagged fish

(simple Petersen estimate), and also helps avoid the potential of re-sampling the same fish if

they are not moving after release (successive capture estimate).

1 Transect 1 (at the north end of the lake) was an exception in that it was comprised of two east-west crossings about 500 m apart because the lake narrows before the outlet. Transect 16 was also an exception; it ran north-south on the east side of the lake at the south end to cover area not reached by Transects 13-15 (the lake is ≈ 2.5 km wide at this point).


June 2002 ••••7

2.2 Spring Sampling

Sixteen cod traps (Figure 2) were deployed on transects across Columbia Lake as described

above from May 29 to June 7, 2001. Traps were checked daily starting at about 0930 hours,

and moved 100 m east after each lift. All sets were 24 hr except for one 48 hr set (June 5-7).

Kokanee bait was changed every 2 days or less. Traps were accessed by a boat launched at

the south end of the lake via the Canal Flats Provincial Park boat launch. The boat used was a

custom fabricated 1996 18’ welded aluminum jet boat with Hummingbird depth sounder.

Captured burbot were placed in a 45-liter plastic tub filled with water into which a solution of

3mg/l clove oil dissolved in 95% alcohol was added (Figure 3; Prince and Powell 2000). Once

fish had been anesthetized with the clove oil mixture, they were checked for the presence of a

previously applied PIT tag or other marks (Figures 4 and 5). The PIT reader was checked to

ensure it was functioning prior to each use. All captured burbot that did not already have a PIT

tag had a PIT inserted under the skin in the left cheek of the fish, just over the operculum

(Figure 6).

In addition to the insertion of a pit tag, a secondary mark (partial pectoral fin clip) was applied to

each burbot. Once processed, burbot were placed in a plastic recovery cooler. Fresh water

was circulated through the recovery cooler by means of an electric bilge pump, to facilitate rapid

recovery (Figure 7). Once the fish had completely recovered, they were released back into the

lake/river near the point of capture (Figure 8). Other species captured (i.e. kokanee, northern

pike minnow) were documented and released.

A 125 m hookless set line was also used over a 2-day period (June 3-5) in an attempt to

increase the sample size. The rope had 8 monofilament lines, each baited with half of a

kokanee, and was deployed at a depth of 2-3 m in the north end of the lake. This method has

worked successfully to capture burbot in other lakes during the winter.

Capture locations of individual fish were identified with a recreational grade handheld Global

Positioning System (GPS) and documented on field data sheets provided by CBFWCP. Water

depths were measured with a Hummingbird depth sounder, while air and water temperatures at

the time of capture were recorded with a digital thermometer.

Water temperatures in Columbia Lake were also collected at trap Number T-12 using a single

Stowaway® TidbiT® temperature logger manufactured by the Onset Computer Corporation,

submerged with the trap. The unit was factory calibrated to yield an error of 0.1 ºC to 0.2 ºC


June 2002 ••••8

and was programmed to record temperatures at 15-minute intervals. The unit was deployed

from May 29 to June 6 2001.

Spring sampling was terminated on June 7, prior to the planned 15 days, because catch rates

were well below the expected 2 fish/trap day and inadequate for a population estimate. A

decision was made to reserve remaining funds for a second capture attempt in the autumn

during the kokanee spawning run.

Figure 2. Typical baited cod trap used in Columbia Lake burbot population study being

deployed.


June 2002 ••••9

Figure 3. Autumn sampling locations on the south end of Columbia Lake near Canal Flats, BC.

Sample Areas


June 2002 ••••10

Sample Sites

R3

R2

R1

Figure 4. Autumn sampling locations on the north end of Columbia Lake and the upper

Columbia River near Fairmont Hot Springs, BC.


June 2002 ••••11

2.3 Autumn Sampling

Autumn trapping was targeted in areas where fish had been concentrated in autumn 1997

radiotelemetry surveys (Figure 3), and at locations where it was suspected that burbot might be

feeding on spawning kokanee (UTM locations are summarized in Appendix A). This included

sites in the Columbia River near the lake outlet (Figure 4). Additional funding was provided to

allow up to 14 days of autumn field sampling. Sampling dates were chosen to coincide with the

peak of kokanee spawning. Traps were checked daily between 07:30 and 19:00 hours October

2 – October 11, 2001. Crews typically arrived at the upper river trap locations at 07:30 hours,

and checked the traps on foot in waders. Lake traps were accessed by boat. Capture locations

and other data were recorded as for the spring sampling.

Figure 5. Anesthetized burbot prior to checking for tags, and processing.


June 2002 ••••12

Figure 6. Burbot being checked for tags/marks prior to being measured. Figure 7. Pit tag reader being used to check adult burbot for previous tags, Columbia Lake.


June 2002 ••••13

Figure 8. Pit tag being implanted in left cheek of adult burbot, Columbia Lake.

Figure 9. Adult burbot in recovery cooler prior to release, Columbia Lake.


June 2002 ••••14

Figure 10. Adult burbot released into Columbia Lake following Pit tagging procedure.

3 Results

3.1 Water Temperature

Columbia Lake is a long, wind swept lake. The large surface area relative to shallow depth

suggests that it warms quickly during the summer and does not stratify. There may be however,

some diversity of temperature conditions if there are areas of groundwater discharge into the

lake similar to the spring-fed spawning tributary.

Calm days were infrequent during the sampling period, which would suggest that the lake is

constantly mixing and well oxygenated because of the frequent wave action. Mean daily water

temperatures at Transect 12 ranged from 13.44 ºC to 17.07 ºC with an overall mean of 15.7 ºC

during the spring sampling period (Figure 11). Minimum and maximum instantaneous

temperatures were 8.69 ºC and 17.28 ºC, respectively. Measured water temperatures during the

fall sampling ranged from 3.9 ºC to 12.2 ºC.


June 2002 ••••15

Columbia Lake Water Temperatures

0

5

10

15

20

29-May 31-May 02-Jun 04-Jun 06-Jun

Sample Date

Wat

er T

empe

ratu

reWater Temperatures

Figure 11. Mean daily water temperatures recorded in trap T-12, Columbia Lake May 29 to June 7, 2001.

3.2 Fishing Effort and Catch

A total of 128 trap-days were sampled during the spring period, with an additional 2 days

sampled with baited set line. During the autumn period, there were 138 trap-days of effort.

Sixteen traps were deployed initially, but one trap was stolen from the upper Columbia River

early in the autumn period. No set lines were deployed during the autumn sampling. River and

lake sampling sites are illustrated in Figures 12-16.

A total of 57 burbot were captured between May 30 and October 11, 2001; 19 during the spring

period and 38 during the autumn period. Catch per unit effort was 0.15 burbot/trap-day in the

spring and 0.28 burbot/trap-day in the autumn. The highest daily capture rates were observed

following replacement of old baits with recently obtained kokanee in the traps. One adult burbot

mortality, apparently unrelated to the trapping, was observed on October 5, 2001. Several


June 2002 ••••16

burbot were observed burrowing into the mud following release in the spring sampling (G.

Smith, pers. comm.).

In addition to burbot, northern pike minnow Ptychocheilus oregonensis, pumpkinseed Lepomis

spp., mountain whitefish Prosopium williamsoni, sucker Catostomus spp., and kokanee

Oncorhynchus nerka were also captured. Several of the captured fish had remnants of kokanee

regurgitated from their mouths when retrieved from the traps (Figure 18). The baits used on the

hookless set lines in the spring also appeared to have been chewed, although no fish were

captured.

Figure 12. Columbia River trap site R-1, October 2001.


June 2002 ••••17

Figure 13. Columbia River trap site R-2, October 2001.

Figure 14. Columbia River site R-3, October 2001.


June 2002 ••••18

Figure 15. Typical cod trap location, Columbia Lake, October 2001.

Figure 16. Typical cod trap location, Columbia Lake, October 2001.


June 2002 ••••19

Figure 17. Northern pike minnow regurgitating kokanee following removal from a cod trap,

Columbia Lake, October 2001.

3.3 Burbot Size, Abundance, and In-lake Distribution

Only three of the 57 captured burbot had been previously tagged at the tributary spawning fence

(Table 3); all three were captured in lake locations (i.e., none in Columbia River) during the

autumn sampling. No burbot tagged during the lake sampling were recaptured in later sets.

Biological data and capture information for individuals is summarized in Appendices A and B.

Table 3. Summary of data on previously tagged burbot captured during trapping in Columbia Lake and River in 2001.

Tag No. Sex Lake Capture

Length in Lake (mm)

Tributary Capture

Length in Tributary

Comments

41363B4367 M 07-Oct-01 380 16-Feb-01 358 First time captured in tributary

4064323E37 M 07-Oct-01 517 16-Feb-01 520 Also spawned in the tributary in 1997 at 464 mm

406439607C F 08-Oct-01 557 12-Feb-01 560 Also spawned in the tributary in 2000 at 532 mm


June 2002 ••••20

Captured fish ranged in length from 170 to 642 mm. There was a clear difference in the size

distribution of the two sampling periods. In the spring, more than half of the burbot were less

than 300 mm, whereas in the autumn most fish were over 325 mm (Figure 18). When both

periods are considered together, the distribution of lake-caught burbot appears to be trimodal;

peaks likely reflect the 2000, 1999, and 1997 cohorts based on age-length of tributary fish (see

Arndt 2002).

Figure 18. Length-frequency distributions for spring and autumn cod trap sampling in Columbia

Lake and River, 2001.

The low sample size precludes a population estimate with precise confidence limits, however,

recapture data were used with Bailey’s modification2 of the simple Petersen estimate as follows

(Begon 1979). Thirteen burbot <300 mm were excluded from the calculations because burbot

less than 300 mm were not tagged at the tributary spawning fence:

Nhat = r (n + 1) (m + 1)

2 Bailey’s modification is recommended for small sample sizes.

200 300 400 500 600 7000

1

2

3

4

5

6

Num

ber o

f Fis

h

Spring

200 300 400 500 600 700

Length (mm)

0

1

2

3

4

5

6

Num

ber o

f Fis

h

Autumn


June 2002 ••••21

1 2 3 4 5 6 70

10

20

30

40

Effo

rt (tr

ap-d

ays)

0

1

2

3

4

5

Num

ber o

f Bur

bot C

aptu

red

Spring

1 2 3 4 5 6 7Depth (m)

0

10

20

30

40

50

Effo

rt (tr

ap-d

ays)

0

2

4

6

8

10

12

14

Num

ber o

f Bur

bot C

aptu

red

EffortCatch

Autumn

Where: Nhat is the population estimate;

r is the number of burbot marked at the tributary = 995;

n is the total burbot in the lake sample = 44; and

m is the number of marked burbot in the lake sample = 3.

Standard error (SENhat) was calculated as (Begon 1979):

SENhat = square root {[r2 (n + 1)(n - m)]/[(m + 1)2 (m + 2)]} The resulting population estimate is 11,194 burbot, with 95% confidence limits (2 x SENhat) of ±

9,557. It was not possible to use the second method of population estimation (successive days

of mark-recapture) because no lake-caught burbot were recaptured.

In the spring, burbot were captured throughout the lake, but the highest capture rates were in

the north (transects 2 and 4). In the autumn, the most effective traps for capturing burbot were

those situated in the north end of the lake near the outlet; two burbot were captured in the river

outlet. Burbot were captured at depths from 1.0 to 6.5 m in the lake, and catch rates tended to

follow the amount of effort at each depth except for slightly higher catches at 4 and 6 m during

the spring sampling (Figure 19).

Figure 19. Burbot catch by depth, in relation to effort, for spring and fall trapping on Columbia Lake in 2001.


June 2002 ••••22

4 Discussion

The low rates of burbot capture in Columbia Lake were contrary to expectations based on

experience with the same traps in other lakes of the Kootenay Region. The small sample

resulted in a population estimate with wide confidence limits that restrict its application to

management and research questions. However, the study still provides useful information for

comparison with earlier research.

There are several possible reasons for the low numbers of burbot captured, which include (but

are not limited to):

i emigration of adult burbot from the lake after spawning;

i high annual mortality rates for adult burbot; and

i ineffective traps (with ineffective bait).

The numbers of burbot captured in the fall (n=37) were almost double those captured during the

summer (n=19). In addition, the majority of spring burbot were smaller than spawning fish

marked at the tributary. This apparent absence of larger burbot during the spring suggests that

they may have left the lake (i.e., moved downstream into Columbia River or Windermere Lake)

after spawning and returned later, possibly as prey species (i.e., kokanee) migrated up from the

Columbia River to spawn near the outlet. In support of this, anglers regard Columbia Lake as a

winter (January to March) fishery for burbot (Arndt 2001b; Cope 2001) and do not target burbot

in Columbia Lake at other times of the year. However, none of the tributary-tagged fish were

caught in the river trapping locations, so there is no direct evidence of tributary fish leaving the

lake. Also, in the radiotelemetry study of post-spawning burbot in 1997-98, no burbot were ever

located outside of Columbia Lake (although not all fish were located every month; Arndt 2001a).

It is possible that post-spawning movements change from year to year depending on conditions

in the lake and river.

The possibility of high annual mortality rates for adult burbot is supported by low percentages of

repeat spawners at the tributary from 1996 to 2001 (<20%; Arndt 2002). In contrast, the

radiotelemetry study of post-spawning fish in 1997-98 did not show any clear mortalities (Arndt

2001a). There were some tracked fish that showed relatively little movement later in the

monitored period, and possibly some mortalities were disguised by imprecision in the locations

or wind-induced movement of tags on the lake bottom.


June 2002 ••••23

Between 1996 and 2001, a total of 4071 burbot were implanted with PIT tags during

enumeration of spawning escapement in a tributary to Columbia Lake. Of these previously-

tagged fish, only three were captured in this study, and all three had been marked at the

tributary in the winter of 2001 (995 fish total). We did not find evidence, in our small sample, that

burbot from earlier tributary spawning events (1996-2000) were still at large in the lake.

Anecdotal reports suggest that avian predators may have an impact on burbot in Columbia Lake

during the summer (Bill Green, pers. comm.), although further investigation is needed before

any conclusions can be drawn. Annual harvest of the winter fishery ranged from about 50 to 500

burbot between 1996 and 2001, and the proportion of tributary-tagged fish in the catch was very

low (≤ 3%; Arndt 2001b).

Ineffective traps seems an unlikely explanation for the low catch rates because we were using

the same traps and bait which was shown to be highly effective on other lakes. It may be,

however, that burbot in Columbia Lake have other abundant sources of food that make baited

traps less effective, particularly in the spring. Another explanation could be that post-spawning

burbot do not actively feed until later in the summer, however, this seems unlikely, and again

contradicts experience on other lakes.

The length range of burbot in this study was similar (ignoring fish <300 mm and allowing for

growth) to that of the tributary spawners in 2001, but the relative size of the 1997 and 1999

peaks suggests that the 1997 cohort was more abundant in the lake than it was in the tributary

spawners. (Figure 20). This suggests that a substantial portion of the 1997 cohort either failed

to mature in 2001, or spawned in locations other than the tributary. If so, the tributary spawner

numbers and size distribution did not parallel spawning conditions or relative abundance in the

lake for 2001. In most years, the catch-per-unit-effort (CPUE) and size distributions in the winter

fishery have followed relative abundance and size of tributary spawners, but in 2001 CPUE was

low while spawner returns were high (Arndt 2001b). Taylor (2001) found the 1997 cohort was

about six times more abundant than the 1999 cohort at age-0; consequently, it would be

expected to be more abundant now unless survival rates after the first summer were very

different.


June 2002 ••••24

Figure 20. Length-frequency distributions of burbot at the spawning tributary (January –

February) and in Columbia Lake and River (spring and fall sampling combined) in 2001. Dominant cohorts in the distribution peaks are based on otolith ages of tributary fish (Arndt 2002). Growth occurred between the spawning and the lake sampling.

Taylor (2001) noted a length threshold of approximately 39 cm length above which he no longer

found burbot in shoreline habitats (based on backpack electrofishing in July). However, in the

spring and autumn trapping in this study, we found larger burbot (50-60 cm) at depths of only 1

m, and smaller burbot (20-30 cm) at depths up to 6 m (the maximum depth of the lake - Figure

21). Depths used by different size classes of burbot may differ depending on the season, or

larger burbot may have avoided capture by the backpack electrofishing method of Taylor.

100 200 300 400 500 600 700

Length (mm)

02468

10121416182022

Freq

uenc

y (%

)2001 Tributary Spawners

1997

1999

100 200 300 400 500 600 70002468

1012141618

Freq

uenc

y (%

)

2001 Lake Sampling 19971999

2000


June 2002 ••••25

Figure 21. Length of individual burbot and their depth of capture in cod-traps in Columbia Lake

in spring and autumn 2001. During autumn, most trapping was done at depths less than 3 m. The dotted line shows the maximum length of shoreline residence found during backpack electrofishing in July (Taylor 2001).

If future population estimates are contemplated, consideration should be given to the following

recommendations:

• Assume relatively low catch rates compared to other lakes and plan for a longer,

intensive collection period;

• Consider that autumn sampling, coinciding with kokanee spawning migration (and

spawning locations), may be more productive than spring sampling;

• Use fresh kokanee bait if available, to improve capture rates;

• Do not use hookless set lines as they were ineffective in summer; and

• Consider expanding the study area beyond Columbia Lake (e.g. Windermere Lake,

Moyie Lake).

10 20 30 40 50 60 70

Length (cm)

1

2

3

4

5

6

Dept

h (m

)SpringAutumn


June 2002 ••••26

5 Literature Cited

Arndt, S. 2000. Data Summary for the 2000 Upper Columbia Burbot Study. Columbia Basin Fish and Wildlife Compensation Program technical report, File 144-35. 8 pp.

Arndt, S. 2001a. Movements of burbot in Columbia Lake, British Columbia, for 18 months after spawning as determined by radio telemetry. Columbia Basin Fish and Wildlife Compensation Program technical report, File 144-38. 8pp.

Arndt, S. 2001b. Summary of Winter Creel Surveys for Columbia and Windermere Lakes from 1995-2001. Columbia Basin Fish and Wildlife Compensation Program technical report, File 134-10. 18 pp. + appendices.

Arndt, S. 2002. Columbia Lake Burbot 2001 Data Summary, 2002 Observations, and Feasibility of Using Night Counts to Index Spawner Abundance. Columbia Basin Fish and Wildlife Compensation Program technical report. 14 pp. + appendices.

Arndt, S.K.A. and J. Hutchison. 2000. Characteristics of burbot spawning in a tributary of Columbia Lake, British Columbia over a four-year period. Pages 48-60 in Burbot Biology, Ecology, and Management, edited by Vaughn L. Paragamian and Dave W. Willis. Publication Number 1. Fisheries Management Section of the American Fisheries Society. Spokane, Washington 2000. 170 pp.

Begon, M. 1979. Investigating Animal Abundance: Capture-Recapture for Biologists. University Park Press, Baltimore, Maryland. 97 pp.

Bernard, D.R., J.F. Parker and R. Lafferty. 1993. Stock assessment of burbot populations in small and moderate-size lakes. North American Journal of Fisheries Management 13:657-675.

Everhart, W.H. and W.D. Young. 1981. Principles of Fishery Science. Cornell University Press, Ithaca. 349 pp.

FISS Database. 2002. Ministry of Fisheries provincial database.

Hutchinson, J. 1996. Upper Columbia Burbot Study. Prepared for the Ministry of Environment, Lands and Parks, Fisheries Branch. 29pp.

McPhail, J.D. and V.L. Paragamian. 2000. Burbot Biology and Life History. Pages 11-23 in Burbot Biology, Ecology, and Management, edited by Vaughn L. Paragamian and Dave W. Willis. Publication Number 1. Fisheries Management Section of the American Fisheries Society. Spokane, Washington 2000. 170 pp.

Prince, A. and C. Powell. 2000. Clove oil as an anesthetic for invasive field procedures on adult rainbow trout. North American Journal of Fisheries Management 20:1029-1032, 2000.

Prince, A. 2001. Local knowledge of Columbia River fisheries in British Columbia, Canada. Report prepared for Columbia-Kootenay Fisheries Renewal Partnership, Cranbrook, B.C. Prepared by Westslope Fisheries, Cranbrook, B.C. 50 pp. + 1 app.


June 2002 ••••27

Scott W. B. and E.J. Crossman. 1973. Freshwater fishes of Canada. Fisheries Research Board of Canada. Bulletin 184. 966 pp.

Spence, C. 2000. A comparison of catch success between two styles of burbot traps in lakes. Pages 165-170 in Burbot Biology, Ecology, and Management, edited by Vaughn L. Paragamian and Dave W. Willis. Publication Number 1. Fisheries Management Section of the American Fisheries Society. Spokane, Washington 2000. 170 pp.

Taylor, J.L. 2001. The Early Life History and Ecology of Columbia Lake Burbot. M.Sc. thesis, University of British Columbia, Department of Zoology. 70 pp.

Taylor, J. and McPhail. 2000. Temperature, development, and behaviour in the early life history of burbot from Columbia Lake, British Columbia. Pages 30-37 in Burbot Biology, Ecology, and Management, edited by Vaughn L. Paragamian and Dave W. Willis. Publication Number 1. Fisheries Management Section of the American Fisheries Society. Spokane, Washington 2000. 170 pp.

Personal Communications

Green, B. 2001. Program Director, Columbia-Kootenay Fisheries Renewal Partnership.

Smith, G. Fisheries Technician, Westslope Fisheries, October 5, 2001.


June 2002

Appendix A

Field Data Forms - Cod Trap Set Summaries From the Columbia Lake Burbot Population Assessment, 2002

DATE IN: 29-May-01DATE OUT: 30-May-01

SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTST15-3 15:30 9:29 1 Bait = 2 kokanee in all trapsT14-2 15:50 9:43 2T13-1 16:05 9:52 1 582298 5559867T12-7 16:20 10:08 4 583082 5561242 Tidbit logger 464252 attached to trapT11-7 16:35 3 582852 5561959T10-5 16:47 10:40 4.5 582263 5562885T9-1 17:00 10:50 5 581222 5564186 just below powerlinesT8-7 17:15 11:00 4.5 582039 5565867T7-3 18:12 11:22 5.5 581254 5566458T6-6 18:24 11:33 5 581510 5567267T5-1 18:40 11:45 5 580239 5567989T4-3 18:50 11:55 5 580572 5568986T3-5 19:00 12:05 5 580927 5570010T2-6 19:11 12:15 5 581288 5570895T1-2 19:23 12:27 1 580815 5571473 1 burbotT16-4 17:50 14:00 3 583865 5560112

Comments:

Columbia Lake Burbot Population Assessment - data sheet

29-May-01: w/t 15.5 C; a/t 20.6 C

NFC - no fish caught; NPM (formerly NSC) - Northern Pikeminnow (formerly Northern Squawfish); CC - Torrent Sculpin;

DATE IN: 30-May-01DATE OUT: 31-May-01

SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTST15-4 9:35 10:15 1 583334 558478 NFCT14-3 9:47 10:35 2 582622 5558888 1 NSC - northern pikeminnow (NPM)T13-2 9:58 10:50 3 582438 5559838 NFCT12-1 10:16 11:00 4 581979 5560983 1 NSC

T11-7 16:35 11:35 3*see May 29th - lost scotchman float, trap still fishing; NFC

T10-6 10:47 11:55 4 582391 5563062 1 NSCT9-2 11:00 12:20 5.5 581353 5564279 NFCT8-1 11:15 12:35 4 581015 55657023 NFCT7-4 11:25 13:22 6 581414 5566568 NFCT6-7 11:40 13:40 4 581669 5567342 NFCT5-2 11:50 13:55 5 580339 5568116 NFCT4-4 12:00 14:15 6.5 580925 5569231 NFCT3-6 12:10 14:23 5 581144 5570174 1 - burbotT2-7 12:18 14:50 3 581508 5571036 NFCT1-3 13:19 15:00 1 580904 5571506 NFCT16-5 14:05 15:20 3 583808 5560335 NFC

Comments:



Trap 12-1 on its side when pulled - 1 burbotT11 trap recovered morning of May 31 & set @ 11-1

DATE IN: 31-May-01DATE OUT: 01-Jun-01

SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTS11-1 9:55 10:23 4 581766 5561252 *located trap and reset - NFC15-5 10:20 9:30 2 583486 5558632 NFC - spawning suckers in area14-4 10:40 9:40 2.5 582850 5558976 NFC13-3 10:45 10:06 3 582592 5559923 NFC12-2 11:10 10:15 4 582110 5561037 tidbit present - NFC10-7 12:05 10:31 3 582642 5563179 1 - adult NSC9-3 12:30 10:48 5 581489 5564323 NFC8-2 12:40 10:57 5.5 581132 5565738 NFC7-5 13:30 11:07 4 581603 5566610 NFC6-1 13:45 11:12 2 580514 5567116 1 - burbot5-3 14:00 12:03 5 580526 5568210 NFC4-5 14:20 12:17 6.5 581128 5569286 NFC3-7 14:40 12:30 3.5 581541 5570287 1 - burbot2-1 15:05 13:02 2 579889 5570796 NFC1-4 15:10 13:10 1 581028 5571543 NFC16-6 15:25 13:38 3 583773 5560634 1 - NSC

Comments:



*Trap recovered & set at new locationFresh bait added (2 kokanee) to old traps

DATE IN: 01-Jun-01DATE OUT: 02-Jun-01

SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTS15-6 9:35 9:32 1.5 583610 5558541 NFC14-5 9:45 9:42 3 583022 5559047 1 - NSC13-4 10:09 9:59 3 582766 5559998 1 - burbot12-3 10:19 10:27 4 582270 5561093 NFC11-2 10:27 10:45 4.5 581817 5561900 NFC10-1 10:40 10:52 4 581240 5562914 NFC9-4 10:53 11:03 5 581605 5564421 NFC8-3 11:00 11:17 5 581282 5565857 NFC7-6 11:10 11:25 2.5 581741 5566798 NFC6-2 12:00 11:49 2 580661 5567221 NFC5-4 12:15 11:58 5.5 580876 5568418 NFC4-6 12:23 12:09 5 581465 5569423 NFC3-1 12:56 12:18 3 579809 5570377 NFC2-2 13:05 12:26 3 579809 5570377 NFC1-5 13:13 12:34 1 581125 5571590 NFC16-7 13:40 13:06 3 583637 5560746 1 - NSC

Comments:



strong winds overnight - high turbidity


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTS15-7 9:40 9:30 1.5 583828 5558678 NFC14-6 9:53 9:41 3 583140 5559267 1 - NSC13-5 10:27 9:51 3 582983 5560186 1 - CC - torrent sculpin12-4 10:37 9:59 4 582491 5561183 1 - NSC11-3 10:46 10:09 5 581941 5562044 NFC10-2 10:58 10:17 4.5 581459 5562970 NFC9-5 11:11 10:26 5 581808 5564477 NFC8-4 11:20 10:37 5.5 581484 5565853 1 - burbot7-7 11:27 11:29 4 581949 5566830 NFC6-3 11:53 11:37 5.5 580912 5567164 1 - NSC5-5 12:00 11:49 6 581086 5568481 NFC4-7 12:11 11:59 3 581650 5569435 NFC3-2 12:20 12:12 6.5 580027 5570350 1 - pumpkinseed2-3 12:29 12:27 4 580554 5571042 NFC1-6 12:38 12:33 1 581303 5571560 NFC16-1 13:10 14:05 2 584148 5559443 NFC

Comments:



Fresh bait added; partially overcast


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTS15-1 9:35 9:57 1 582775 5558195 NFC14-7 9:45 10:08 3 583482 5559370 NFC13-6 9:53 10:33 3 583236 5560165 NFC12-5 10:01 10:25 4 582674 5561179 NFC11-4 10:12 10:44 4.5 582120 5562048 NFC10-3 10:20 10:53 4.5 581687 5562977 NFC9-6 10:30 11:03 5 582035 5564490 NFC8-5 10:40 11:15 4.5 581675 5565842 NFC7-1 11:33 11:49 2.5 580703 5566516 NFC6-4 11:40 11:55 5.5 581163 5567293 NFC5-6 11:52 12:01 5.5 581333 5568543 NFC4-1 12:03 12:12 5.5 579961 5569081 1 - CC - torrent sculpin3-3 12:15 12:21 6 580336 5570242 NFC2-4 12:30 12:27 4 580792 5571023 2 - adult NSC1-7 12:35 12:36 1 581373 5571610 NFC16-2 14:07 13:12 2.5 584064 5559624 NFC*T2-7 13:40 12:47 2 to 3 581524 5571181 NFC

Comments:



*Set Line - all bait had been chewed on but no fish were captured. Some bait appeared to have been swallowed, partially digested and then spit out


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTS15-2 10:01 9:40 1.5 582979 5558303 1 - burbot14-1 10:16 10:09 2 582261 5558965 NFC13-7 10:35 10:18 3 583415 5560213 NFC12-6 10:27 10:26 4 582877 5561219 NFC11-5 10:47 10:35 4.5 582289 5562091 NFC10-4 10:56 10:43 4.5 581919 5562981 NFC9-7 11:08 10:51 3 587294 5564544 NFC8-6 1:18 11:00 5 581879 5565871 NFC7-2 11:52 11:02 3.5 580854 5566577 NFC6-5 11:58 11:24 5.5 581313 5567295 NFC5-7 12:07 11:32 2 581553 5568570 NFC4-2 12:16 11:41 5 580175 5569321 1 - burbot3-4 12:23 12:12 5.5 580597 5570253 NFC2-5 12:31 12:21 4 581020 5571013 3 - burbot1-1 12:41 12:56 2 580532 5571345 NFC16-3 13:16 13:28 3 583627 5559847 NFC

*T1-7 SL1 12:53 13:05 2 to 3 581383 5571462 NFC

Comments:



*set near outlet: bait chewed on but NFC


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTS15-3 9:42 5:47 2 583237 5558438 NFC14-2 10:11 5:58 2.5 552448 5559070 NFC13-1 10:22 6:17 3 582229 5559826 NFC12-7 10:30 6:35 3 583198 5561364 tidbit datalogger out @ 6:35; NFC11-6 10:39 10:31 4.5 582474 5562221 NFC10-5 10:46 10:18 5 582143 5563043 NFC9-1 10:55 10:09 3.5 581090 5564296 1 - CC - torrent8-7 11:03 9:41 3 582110 5565956 1 - burbot6-6 11:28 9:03 4.5 581613 5567372 NFC5-1 11:37 8:55 3 580056 5568527 NFC4-3 11:49 8:21 6 580604 5569443 4 - burbot3-5 12:16 8:12 6 580981 5570348 NFC2-6 12:23 7:43 4 581361 5571078 1 - burbot1-2 13:00 7:35 1 580690 5571470 NFC16-4 13:30 6:24 3 584012 5559865 NFC*7-3 11:18 9:11 3 580829 5566603 1 - burbot*SL1

Comments:



not settraps pulled - removed tidbit temperature data logger from T12 trap

DATE IN: 02-Oct-01DATE OUT: 03-Oct-01

SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTST-4 11:16 10:15 1 582899 5558390 Water Temp 11.3 deg C NFCT-11 11:36 10:23 2 582860 5559095 NFCT-16 11:53 10:37 3 582399 5560191 1 NPM (NFC) Fresh baitT-10 12:19 10:53 2 582616 5563371 NFC/Fresh baitT-07 12.38 11:07 4 581967 5564342 NFC/Fresh baitT-92 12:53 11:15 2 581635 5567077 NFCT-55 13:02 11:19 3 581702 5567576 NFCT-98 13:17 11:26 4 580163 5568676 NFC/Fresh baitT-57 13:40 11:37 2 580643 5571408 1 burbotT-15 13:43 11:35 1 580614 5571379 NFC/Fresh baitT-12 13:50 12:32 3 580904 5571017 1 burbot 24.5 cmR-1 15:45 14:30 1 581931 5572722 picture #15 NFCR-2 16:05 14:15 1 581723 5573040 picture #16 NFCR-3 16:20 14:03 2 581465 5573583 #14# picture #17 - NFC

Comments:


picture #33, 34 - no picture - sheep @ site R-1

NFC - no fish caught; NPM (formerly NSC) - Northern Pikeminnow (formerly Northern Squawfish); CC - Torrent Sculpin; R - River


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTST-4 10:18 9:50 1 582879 5558390 Water Temp 12.2 deg C - NFCT-11 10:29 10:00 2 582506 5559039 NFC/Moved 04.10.01 added baitT-16 10:39 10:10 3 582362 5560139 added fresh bait - moved trap to N endT-10 10:55 10:25 2 582624 5563377 1 burbot (54.9 cm)T-7 11:10 11:03 4 581967 5564342 NFC - moved to N endT-92 11:16 11:10 2 581623 5567085 NFC (1 mature sucker 6 cm) picture #18T-55 11:20 11:18 1 581778 5567553 fresh bait NFCT-8 11:27 11:21 5 580166 5568660 fresh bait NFCT-12 12:33 13:15 3 580904 5571017 fresh baitT-15 11:37 12:20 1 580614 5571379 fresh bait; burbot picture #19, 20 NFCT-57 11:52 12:47 2 580727 5571325 fresh bait NFCT-98 12:21 11:49 3 580731 5571120 new trap NFCT-83 12:30 13:00 3 581458 5571343 new trap R-1 14:30 15:12 1 581931 5572722 NFC fresh baitR-2 14:15 14:59 1 581723 5573040 NFC fresh baitR-3 14:05 14:48 2 581465 5573583 NFC fresh bait

Comments:




SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTST-4 9:55 10:00 1 583165 5558539 Moved to N endT-11 10:05 10:10 2 582333 5559080 NFC, moved to N endT-16 11:00 10:30 2 582620 556332 NFC fresh baitT-10 10:55 10:26 2 582656 556334 NFC fresh baitT-7 11:41 11:40 2 581224 5571507 NFC fresh baitT-92 11:37 11:45 2 580957 5571404 NFC fresh baitT-55 11:30 13:27 2 580338 5571119 NPM fresh bait, pic #31T-8 11:28 13:35 3 557902 5570744 NFC, moved T-12 13:20 13:13 3 580803 5571242 NFCT-15 12:23 12:38 1 580603 5571292 1 burbot 04.10.01 picture 19, 20T-57 12:49 11:49 2 580768 5557406 1 burbot 57.7 cm pic #25, 26, 27, 28T-98 12:18 12:30 3 580663 5571388 NFC fresh baitT-83 13:05 11:20 3 581388 5571488 NFC fresh baitR-1 15:21 14:47 4 581436 5573886 photo 21, 23 deploying trapR-2 15:26 14:45 3 581436 5573886 photo 22R-3 14:52 14:43 2 581465 5573583

Comments:



found dead burbot in 2m water, no tag 45 cmused for bait, *T-15 out 12:39; 1 burbot 05.10.01 picture #29-30


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTST-4 10:56 11:51 3 581435 5571177T-11 11:00 11:54 2 551133 5571398 1 immature whitefishT-16 10:35 11:42 3 582362 5556039 1 whitefish 14"T-10 10:28 11:13 3 582620 5563396 1 burbotT-7 11:40 12:01 2 5581224 5571507 NFC fresh baitT-92 11:47 12:04 2 580957 5571404 NFCT-55 13:30 12:21 2 580338 5571119 NFCT-8 13:40 12:09 2 580748 5571365 NFCT-12 13:15 12:07 3 580803 5571242 NFCT-15 12:40 12:19 1 580603 5571292T-57 11:53 12:10 2 580768 5571406 pic #26, 25, 27, 28; 57.7 cm burbotT-98 12:33 12:13 3 580663 5571388 NFCT-83 11:30 11:46 3 581383 5571488 1 NPM (18")R-1 14:55 9:35 4 581436 5573886 10 kokaneeR-2 14:45 9:15 3 581436 5557386 1 burbot, 9 kokaneeR-3 14:41 9:00 2 581465 5557583 NFC

Comments:



found dead 45 cm burbot in 2m water; used for bait05.10.01 T-15 - picture #29-30


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTSR-3 9:05 9:00 2 581465 5557583 NFC, trap stolenR-2 9:20 9:01 3 581436 5573886 12 kokanee approx.R-1 9:36 9:30 4 581436 5573886 NFCT:10 11:14 10:34 3 582620 5563398 NFCT:16 11:45 10:40 3 582362 5560391 1 NPM ~ 16" roll 1 photo 35T-83 11:48 12:11 3 581383 5571343 NFCT-4 11:53 10:53 3 581423 5571205 2 pit tags present, 3 burbotT-11 11:56 12:18 2 551113 5571398 1 burbotT-7 11:59 12:17 2 581224 5571507 1 MNWH ~ 20"T-92 12:06 12:34 2 580957 5571404 NFCT-12 12:07 13:10 3 580803 5571242 NFCT-8 12:10 12:39 2 580748 5571365 1 - 18" MNWHT-57 12:11 12:37 2 580768 5571406 NFCT-98 12:16 12:44 3 580663 5571388 1 burbot, picture #5T-15 12:20 12:41 1 580603 5571292 NFCT-55 12:23 13:14 2 580338 5571119 1 18" MNWH

Comments:



T-4 - 3 burbot - 2 pit tags present - tagged 1T-11 1 burbot; pictures #33, 34 - no picture - sheep @ Site R-1T-98 - lesion forehead & right side in front of dorsal picture #5


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTSR-2 9:04 9:10 3 581436 5573886 1 burbot; Roll #2, pic #6R-1 9:35 10:00 4 581436 5573886 10 kokaneeT-10 10:46 10:56 3 582620 5563396 NFCT-16 10:42 10:58 3 582362 5560391 1 burbot, photo #7T-4 11:13 11:38 3 581423 5571205 1 burbotT-83 12:12 12:07 3 581383 5531343 NFCT-07 12:18 12:15 2 581224 5571507 1 burbotT-11 12:20 12:27 2 551113 5571398 NFCT-92 12:35 12:37 2 580957 5571404 NFCT-57 12:38 12:42 2 580768 5571406 1 burbotT-8 12:39 13:15 2 580748 5571365 NFCT-15 12:41 13:19 1 580603 5571292 NFCT-98 12:46 13:17 3 580663 5571388 NFCT-12 13:12 12:37 3 580803 5571242 NFCT-55 13:161/13/1900 13:21:00 AM 2 580338 5571119 NFC

Comments:


T-16 yellow spot left side before dorsal & left lower jaw, healthy fish, kokanee in stomach



SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTSR2 9:15 9:10 3 581454 5573516 NFCR-1 10:05 8:55 4 481436 5573886 NFC, 1 dead muskrat ~ 10"T-10 11:45 10:28 3 581480 5571184 2 burbot, 1NPMT-16 11:10 10:16 3 582362 5560391 NFCT-4 11:50 11:28 3 581423 5571205 1 burbotT-83 12:10 11:48 2 581369 5571482 1 burbot, 1 NPMT-11 12:32 12:14 2 551113 5571398 NFCT-92 12:34 12:18 2 580957 5571404 NF moved to E side near mouthT-12 12:38 12:30 2 580303 5571242 1 burbotT-57 12:45 12:39 2 580768 5571406 NFCT-8 13:07 12:48 2 580748 5571365 1 burbot, 1 NPMT-98 13:20 13:02 3 580663 5571388 NFCT-15 13:39 13:06 1 580603 5571292 NFC, moved to east sideT-55 13:24 13:12 2 580338 5571119 1 NPM, moved to east side

Comments:



T-10. T-7 - 1 NPM; out 12:08; picture #17 & 18 floats on east side of lake Oct 9


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTSR-1 9:00 9:15 3 581454 5573516 moved to lake; NE sideR-2 9:15 9:20 3 581436 5573886 trap tipped overT-16 10:48 10:32 3 582362 5560391 moved to the NE of lake near mouthT-10 10:32 10:52 3 581480 5571184 3 burbot 1 NPMT-4 11:32 11:45 3 581423 5571205 NFCT-83 12:00 12:11 2 581369 5571482 NFCT-7 12:09 12:14 1 581300 5571575 NFCT-11 12:10 12:19 551113 5571398 NFCT-92 12:20 12:43 581412 5571433 NFCT-12 12:36 11:26 580803 5571242 1 burbotT-57 12:40 12:36 580768 5571365 NFCT-8 12:52 12:30 2 580759 5571360 NFCT-98 13:03 12:28 2 580663 5571388 NFCT-15 13:38 11:47 581446 5571288 1 burbotT-55 13:29 2 81056 5571441 NFC

Comments:



T-10-1 - pic #19/T-10-2 - pic #20/T-10-3 pic #21


SITE TIME IN TIME OUT DEPTH (M) EASTING NORTHING COMMENTSR-1 10:58 12:05 581372 5571280 new lake 87; 1 live kokaneeR-2 9:30 9:35 581436 5573886 NFCT-16 10:59 12:48 581311 5571460 NFCT-10 10:57 10:52 581480 5571184 3 burbotT-4 11:46 11:43 581423 5571205 1 burbotT-83 12:13 12:23 581369 5571482 2 burbotT-7 12:20 12:53 581300 5571575 2 burbotT-11 12:22 13:16 581113 5571398 NFCT-92 11:44 12:08 581412 5571433 1 burbot, 1 NPMT-12 11:27 13:28 580803 5571242 1 burbotT-57 12:36 13:24 580768 5571365 NFCT-8 12:35 13:34 580759 5571360 NFCT-98 12:30 13:41 580663 5571388 NFCT-15 11:50 11:39 581446 5571288 NFCT-55 12:36 13:20 581056 5571441 NFC

Comments:



Visitor stated on eve of Oct 10 (ling) (burbot) spotted at bridge at Spruce Grove at Meter stick just south of bridge


June 2002

Appendix B

Field Data Forms – Individual Fish Capture Data From the Columbia Lake Burbot Population Assessment, 2002

Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments30-May-01 T15-3 NFC

T14-2 NFCT13-1 NFCT12-7 1 adult NSC - northern pike minnowT11-7 no Scotchman float - recovered float, trap not visibleT10-5 NFCT9-1 NFCT8-7 NFCT7-3 NFCT6-6 NFCT5-1 NFCT4-3 NFCT3-5 NFCT2-6 NFCT1-2 no 415009106A clip right pect. 54.7 Healthy, relatively thin, likely spawnedT16-4 NFC

weather @ 14:30 - still windy from south, some turbidity

Columbia Lake Burbot Population Assessment - data sheetWeather and Water Conditions

Wind dir./speed:Wave height:

windy from South0.6 m chop

W/T: 15.6 C high overcast12.8 @ 10:16 hrs

Comments:Strong winds May 28 - 30th resulting in high lake turbidityBurbot captured pit tagged on left cheek

A/T:


Weather and Water Conditions

Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments31-May-01 15-4 NFC

14-3 1 adult NSC13-2 1 cc - sculpin12-1 no 4150167177 right pect. 21.6 Left cheek10-6 1 - cc9-2 NFC8-1 NFC7-4 NFC6-7 NFC5-2 NFC4-4 NFC3-6 no 41501A2008 right pect. 36.1 Left cheek2-7 NFC1-3 NFC16-5 NFC


Comments:All fish released healthy

W/T:A/T:



15.5 deg c18.4 deg c @ 11:05calm in morning, light afternoon from Southflat to 0.1m chop

Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments01-Jun-01 15-5 NFC

14-4 NFC13-3 1 adult NSC (large)12-2 NFC11-1 NFC10-7 1 adult NSC (large)9-3 NFC8-2 NFC7-5 NFC6-1 no 415011656C clip right pect. 25.7 Left cheek5-3 NFC4-5 NFC3-7 no 415011656C clip right pect. 36.4 Fish relatively thin with some scars, likely spawned2-1 NFC1-4 NFC16-6 1 - NSC

Comments:


W/T:A/T:


Columbia Lake Burbot Population Assessment - data sheetWeather and Water Conditions

16.8 deg C22.3 deg C @ 10:45light winds from South/SEcalm to 0.3 m in afternoon


14-5 1 adult NSC

13-4 no 41602C7712 right pect. 41.8Scars on sides. Healthy fish with scars on sides, released and swam immediately to bottom

12-3 NFC11-2 NFC10-1 NFC9-4 NFC8-3 NFC7-6 NFC6-2 NFC5-4 NFC4-6 NFC3-1 NFC2-2 NFC1-5 NFC16-7 1 - NSC

Comments:


Columbia Lake Burbot Population Assessment - data sheetWeather and Water ConditionsW/T:A/T:Wind dir./speed:Wave height:

15.9 deg c @ 10:4514.8 deg cstrong from south/sw0.4m to 1.1 m



14-6 1 - NSC13-5 1 - CC12-4 1 - NSC11-3 NFC10-2 NFC9-5 NFC8-4 41500E4A60 right pect. 35.4 1burbot*7-7 NFC6-3 1 - NSC5-5 NFC4-7 NFC3-2 1 - pumpkinseed2-3 NFC1-6 NFC16-1 NFC

Comments:


W/T:


A/T:Wind dir./speed:Wave height:

15.4 deg c @ 10:00 am14.7 deg c @ 10:00 ammoderate from north/ne0.3 - 0.7 m chop - turbid

*pit tag in left cheek scars on side & tail**NB - TEST SET LINE (8 lines 125' rope) baited with 1/2 kokanee set @13:40 hours @ site T2-7



14-7 NFC13-6 NFC12-5 NFC11-4 NFC10-3 NFC9-6 NFC8-5 NFC7-1 NFC10-4 NFC5-6 NFC4-1 1 - CC - torrent sculpin3-3 NFC2-4 2 - adult NSC1-7 NFC16-7 NFC

Comments:



W/T:A/T:

13.2 @ 10:3014.8 @ 10:30

0.1 m to 0.6 m (turbid in morning, clearing)Wind dir./speed: moderate to light from North, moderate from SE in afternoon; partially overcastWave height:

SL1 - set line all bait partially eaten, some appeared to be swallowed, partially digested but NFC


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments05-Jun-01 overcast, light rain

15-2 no 416021212F1C right pect. 21.9 1 - burbot, (left cheek)14-1 NFC13-7 NFC12-6 NFC11-5 NFC10-4 NFC9-7 NFC8-6 NFC7-2 NFC6-5 NFC5-7 NFC4-2 no 415031095D right pect. 36.4 left cheek3-4 NFC2-5 no 415031703C right pect. 23 left cheek2-5 no 4150095130 right pect. 20.1 left cheek2-5 no 4150041B74 right pect. 26.5 left cheek1-1 NFC16-3 NFCSL1 NFC

Comments:


W/T:


A/T:light from SW, changing to moderate from SE in afternoon0.1m to 0.6 m

14.4 deg c @ 10:3014.8 deg c @ 10:30

Wave height:Wind dir./speed:


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments07-Jun-01 15-3 NFC - partially overcast

14-2 NFC13-1 NFC12-7 NFC11-6 NFC10-5 NFC9-1 1 - CC (torrent sculpin)4-3 no 4150160264 clip right pect. 31.5 tagged in left cheek4-3 no 4150111265 clip right pect. 22.5 tagged in left cheek4-3 no 4150207D3B clip right pect. 25.5 tagged in left cheek4-3 no 4150304758 clip right pect. 23.2 tagged in left cheek3-5 NFC2-6 no 415012581D clip right pect. 56.6 tagged in left cheek1-2 NFC7-3 no 41501D1E62 clip right pect. 24.8 left cheek16-4 NFC8-7 no 4150063041 clip right pect. 38.9 healthy active fish6-6 NFC5-1 NFC

Comments:


W/T:



13.9 deg c @ 6:359.0 deg c @ 6:35calm to moderate from Southflat to 0.4 m chop

All fish released healthy & active; swam to bottom immediately; appear to burrow in mud;


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments03-Oct-01 T-4 NFC

T-11 NFCT-16 1 NPM.T-10 NFCT-7 NFCT-92 NFCT-55 moved fresh bait NFCT-98 fresh baitT-12 24.5 1 burbot, fresh baitT-15 NFC, fresh baitT-57 no 41501C3633 right pect. 55.1 wt 11.2 deg C, left pectoral, 1 burbotR-1 NFCR-2 NFCR-3 NFC

Comments:


W/T:



12.2 C; 11:47 a.m. - 11.2 13.2 C; 11:47 - 8.7 Clight from north


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments04-Oct-01 T-4 NFC, fresh bait

T-11 NFC, fresh baitT-16 NFC, moved to North endT-10 no 415032235F right pect. 54.9 1 burbot (mature)T-7 NFCT-92 immature sucker (6 cm)T-55 NFC, move to N endT-8 NFC, move to N endT-12 NFC, fresh baitT-15 no 4502B1717 right pect. 52.4 1 burbot picture #19,20T-57 NFC, fresh baitT-98 NFC, fresh baitT-83 NFC, fresh baitR-1 NFCR-2 1 kokanee (M)R-3 NFC

Comments:


W/T:



9.0 C8.6 Cam. - noneam - none


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments05-Oct-01 T-4 NFC, moved to N end

T-11 NFC, moved to N endT-16 NFC, fresh baitT-10 NFC, fresh baitT-7 NFC, fresh baitT-92 NFC, fresh baitT-55 NPM, picture 31T-8 NFC, fresh baitT-12 NFC, fresh baitT-15 no pit tag 41500D4E09 right pect. 58.1 1 burbotT-57 no pit tag 415011367C right pect. 57.7 1 burbot, picture #25, 26, 27, 28)T-98 NFC, fresh baitT-83 NFC, fresh baitR-1 NFCR-2 NFCR-3 NFC

Comments:


W/T:


A/T:Wind dir./speed:

Wave height:

8.2 C1.9 Cnonenone

found one dead burbot, picture # 24-45 cm; used for bait;05-10-01; T-15 picture #29-30


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments06-Oct-01 R-2 none present 4150162E3B right pect. 37.1 1 burbot, photo #33 (9 kokanee)

R-3R-1 NFC, (10 kokanee)T-10 none present 41502B3019 right pect. 24.1 1 burbot, no tag present, lesions right pec

Comments:


W/T:



3.9 C-3.5 CS-N;6"


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments07-Oct-01 R-2 NFC

R-1 NFCT-10 NFCT-16 NPMT-4 no 4150113814 right pect. 62.1 burbotT-4 41363B4367 right pect. 38 burbotT-4 4064323E37 right pect. 51.7 burbotT-11 none 4150273D3D right pect. 63 burbot, picture #4 Roll 2T-98 none 4150295230 right pect. 49.5 burbot, picture #5

Comments:



W/T:A/T:Wind dir./speed:Wave height:

5.8 C10.8 CS.W.none

T-4 caught 3 burbot on reel fresh kokanee; T-4 (2) left pectoral deformed; Roll #2/pic 1-2 (recovery); picture #3 Roll #2 (anaesthetic)T-11 (1) - burbot yellow spot on left abdomen, dark brown spot on right abdomen


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments08-Oct-01 R-2 none 41500D601D right pect. 34.4 1 burbot

T-16 none 40643C530E 55.2 1 burbotT-4 none 4150230956 56.2 1 burbot, pic #8

T-07 nonedorsal lobe of

caudal fin 17 Too small to pit tag, pic #9,T-57 406439607C right pect. 55.7 1 burbot healthy fish

Comments:


W/T:



10.3 C5 CS to N0.5 m

T-4 yellow spot under right pectoral; T-57 yellow spot on back (left side)


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments09-Oct-01 T-10 none 4150180E04 right pect. 53 no tag present, 2 burbot, pic#10 1 NPM (55 cm)

T-10 none 41500C7D77 right pect. 53.7 1 kokanee tail sticking out of mouth, pic #11, 12T-4 none 415024592E right pect. 60 no tag present, 1 burbot, pic #13 healthyT-83 none 41501E191C right pect. 58.2 no tag present, pic #14, 1 burbot, 1NPMT-12 none 41500B623D right pect. 42.5 no tag present, 1 burbot, pic #15T-8 none 41502D584E right pect. 41.5 no tag present, 1 burbot, pic #16 1 NPM

Comments:


T-10 (1) - lesion on left side/yellow spot on lower left gill cover; T-83 - yellow spots on lower jaw & left side below dorsal; T-57 yellow spot on belly


W/T: 9.6 CA/T: 6.1 CWind dir./speed: SWWave height: 0.45m


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments10-Oct-01 T-10 none 41500F283A right pect. 58.6 pic #19

T-10 none 416026094E right pect. 54.2 pic #20T-10 none 4150166F61 right pect. 52.5 pic #21T-15 none 4160303568 right pect. 64 pic #22T-12 none 4160261342 right pect. 40.4 1 burbot, pic #23

Comments:


W/T:



10.0 C8.4 CSW0.5 m

T-10 - yellow spot on belly behind right pec. T-10-3 - yellow spot on right pec and dorsal fin. T-15 - yellow spoton left gill cover and anal fin


Date Site Pit No. present Pit No. added Second Mark Length (cm) Comments11-Oct-01 T-10 no tag present 41502B255E right pect. 64.2 Roll #2, pic #24

T-10 no tag present 4150085A75 right pect. 45.2 Roll #3, pic #1T-10 no tag present 406426066C right pect. 42 Roll #, pic #2T-4 no tag present 41501E0310 right pect. 43.1 Pic #3T-92 no tag present 41500E2765 right pect. 40.1 pic #4T-83 no tag present 4150247B19 right pect. 56.2 pic #5T-83 no tag present 415008B4533 right pect. 52.5 pic #6T-7 no tag present 41502A7911 right pect. 49.8 pic #7T-7 no tag present 415029307E right pect. 41.3 pic #8T-12 no tag present 41500A1A6B right pect. 38.8 pic #9, 1 burbot

Comments:



9.0 C6.7 CNE

W/T:A/T:Wind dir./speed:

0.25m

T-10-1 yellow spot on left by anal fin and right side ahead of vent. # of red spots on lower jaw. T-10-2 - net scars from dorsal fin back to tail. T-92-1 net scar behind pec fins and tail. T92-2 yellow spot on right side of jaw lower. T-7-1 - yellow spot on R pec. T-7-1 growth on R. side below dorsal. T-12 right side has 2 small growths

Wave height:

j.e. bisset, s.k.a. arndt, r.s. cope · 2013. 5. 9. · columbia lake burbot population estimate...

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