aspects of the life history of shelagyote river adult …aspects of the life history of shelagyote...

Aspects of the Life History of Shelagyote River

Adult Bull Trout (Salvelinus confluentus)

Paul A. Giroux, M.Sc. R.P.Bio.

Fish & Wildlife Science and Allocation Branch Skeena Region

BC Ministry of Water, Land and Air Protection 3726 Alfred Avenue,

Bag 5000 Smithers BC

December, 2001

SK - # 131

Shelagyote River Bull Trout Life History i

Abstract The Shelagyote River, a major tributary to the Babine River, is currently inaccessible by road and is scheduled for forestry development in the near future. In an effort to assist with the planning process to address and possibly protect fisheries resources, bull trout (Salvelinus confluentus) studies were initiated in 2000 by Skeena Region’s Fisheries Section of the BC Ministry of Environment (now Min. of Water, Land and Air Protection). Initial sampling and design efforts focused on capturing adult bull trout for purposes of conducting radio telemetry studies, however, too few bull trout were encountered during spring sampling efforts in the Shelagyote River to justify the preferred approach. As a result adult Shelagyote River bull trout were sampled over two seasons exclusively by angling during suspected migration and over-wintering periods. A total of 38 bull trout were captured and handled over the course of the study. Staging, pre- and post-spawn habitats were identified; however attempts to identify of spawning locations were inconclusive. Bull trout immigration from the Babine River, staging, spawning and emigration were related to river water temperatures and associated dates are presented. Shelagyote River bull trout spawning migrations appeared to be consistent with others who observed movement to spawning location in association with water temperatures of 9-10oC. Management options for planning and population conservation are discussed.

Shelagyote River Bull Trout Life History ii

Acknowledgements Funding for this project was provided by Forest Renewal BC. Fisheries and Habitat Section and Conservation Officer staff from BC Ministry of Water Land and Air Protection, Skeena Region, contributed field time and expertise. In particular, Dana Atagi, Mark Beere, Darren Fillier, Sig Hatlevik, Kevin Nixon and Ron Tetreau are acknowledged for their assistance with field work. Matt Jessop of the Min. of Sustainable Resource Management also assisted with field work and administration. Jason Harris, Jason Dorey, Jessie Anaka and David Taft of Triton Environmental are also acknowledged for their assistance with field data collection and information sharing. Todd Mahon of Wildfor Consultants is also acknowledged for his contribution to field sampling. Canadian Helicopters pilots, Tom Brookes and Darryl Hatzic are also acknowledged for providing safe and efficient flight services. Mark Beere is acknowledged for providing editorial and critical comments on the draft report.

Shelagyote River Bull Trout Life History iii

Table of Contents ACKNOWLEDGEMENTS ............................................................................................................... II

TABLE OF CONTENTS................................................................................................................. III

LIST OF FIGURES......................................................................................................................... IV

LIST OF TABLES........................................................................................................................... IV

1.0 INTRODUCTION ...........................................................................................1

2.0 METHODS.....................................................................................................2 2.1 Fish Sampling ......................................................................................................................... 2

2.1.1 Timing & Location.............................................................................................................. 2 2.1.2 Fish Capture and Handling ............................................................................................... 3 2.1.3 Fish Gender Determination ............................................................................................... 3 2.1.4 Fish Maturity Determination .............................................................................................. 4

2.2 Habitat Assessment ............................................................................................................... 5 2.2.1 Stream Habitat Inspections ............................................................................................... 5 2.2.2 Water and Air Temperature Monitoring............................................................................. 5

3.0 RESULTS ......................................................................................................6 3.1 Fish Sampling ......................................................................................................................... 6 3.2 Bull Trout Sampling ............................................................................................................... 8

3.2.1 Length-at-Age.................................................................................................................... 8 3.2.2 Maturity.............................................................................................................................. 9 3.2.3 Run Timing & Gender Differences .................................................................................... 9

3.3 Habitat Assessment ............................................................................................................. 11 3.3.1 Water and Air Temperatures........................................................................................... 11 3.3.2 Spawning Habitat Inspections......................................................................................... 13

4.0 DISCUSSION...............................................................................................13 4.1 Bull Trout Run-Timing & Movement ................................................................................... 13 4.2 Spawning Locations............................................................................................................. 15 4.3 Growth and Maturity............................................................................................................. 15 4.4 Habitat and Temperature ..................................................................................................... 16 5.0 CONCLUSIONS ..........................................................................................16

6.0 RECOMMENDATIONS ...............................................................................17

7.0 REFERENCES ............................................................................................19

8.0 APPENDICIES.............................................................................................21 8.1 Appendix ‘1’: Catch and site data...................................................................................... 21 8.2 Appendix ‘2’: Beere, 2000 and Giroux, 2000 Trip Reports ............................................. 22

Shelagyote River Bull Trout Life History iv

List of Figures Figure 1: Location of the Shelagyote River watershed in the Skeena Region................................ 2 Figure 2: Sample site locations within the Shelagyote River watershed, April 26, 2000 – Nov. 8,

2001. ....................................................................................................................................... 3 Figure 3: Example of dorsal and lateral view of mature female bull trout head. ............................ 4 Figure 4: Male bull trout kelt (63.5 cm fork length). Note dark green head, developed kipe, faded

orange ventral colouring and lateral red spots. ...................................................................... 4 Figure 5: Location of temperature loggers (triangles) and stream reaches inspected (circles) to

locate spawning bull trout or bull trout redds. ......................................................................... 5 Figure 6: Catch locations for bull trout (BT), steelhead (ST), coho salmon (CO) and rainbow trout

(RB) within the Shelagyote River watershed for all sampling events (April & Sept., 2000, August, September and November 2001). ............................................................................. 7

Figure 7: Summary of fish abundance and species richness, by site within the Shelagyote River watershed (CH – chinook, RB – rainbow trout, CO – coho, ST – steelhead, BT – bull trout).8

Figure 8: Length class frequency and mean age (± SE) for bull trout captured in the Shelagyote River watershed between March 2000 and November 2001. ................................................ 8

Figure 9: Percentage of bull trout captured in the Shelagyote River watershed identified as being mature presented by size class. Mean age of bull trout is also plotted on the second axis.. 9

Figure 10: Percent maturity of captured bull trout and number of bull trout captured on sampling events from April 26, 2000-to-Nov. 8, 2001 in the Shelagyote River watershed.................. 10

Figure 11: Male:female sex ratio for bull trout captured in the Shelagyote River between August 20 and Nov. 8, 2001. 1:1 line represents equal male:female ratio. Numbers presented in bars represent number of fish............................................................................................... 11

Figure 12: Five-day running mean water temperature data (degrees Celsius) for Shelagyote River at Cayuse Jack Cr. (grey line) and at the Babine River confluence (black line), as well as, air temperature at the Shelagyote Babine River confluence (dashed line) from May 5, to November 8, 2001. ............................................................................................................... 12

Figure 13: Five-day running mean water temperature (degrees Celsius) for the Shelagyote (black line), Babine River (dark grey line) and unnamed lake headed tributary (light grey line) to the Shelagyote River beginning on May 4, and ending July 9th (unnamed trib) and July 16th (Babine), 2001. ..................................................................................................................... 12

Figure 14: Approximate annual life history stages of adult Shelagyote River bull trout in relation to Shelagyote River five day running mean water and ambient air temperature (degrees Celcius). ................................................................................................................................ 14

List of Tables Table 1: Summary of fish length (fork length) and age for bull trout only....................................... 6 Table 2: Summary of water and air temperatures (degrees Celsius) recorded hourly at stations

located in the Shelagyote River at the Babine River confluence and Cayuse Jack Cr. confluence............................................................................................................................. 11

Table 3: Summary of physical parameters measured at representative sites within reaches waked by field crews during suspected spawning site inspections. ..................................... 13

Shelagyote River bull trout life history 1

1.0 Introduction The Shelagyote River watershed (Fig. 1) has been the focus of recent biological studies, including bull trout (Salvelinus confluentus), due to impending resource development and access planning (Darren Fillier, pers. comm.). Bull trout studies had not been conducted previously in the Shelagyote River watershed or its parent stream, the Babine River watershed; however, it was speculated that the Shelagyote River provided important bull trout habitat (Robert Stewart, pers. comm.). The Shelagyote River is located in the BC Ministry of Forests, Kispiox Forest District (FD). The Kispiox FD is presently managed in accordance with the 1996 Kispiox Land and Resource Management Plan (LRMP; Anonymous, 1996). The Kispiox LRMP stipulates that known bull trout spawning, rearing areas, as well as, reaches identified with populations of bull trout are to be provided with protection from development and habitat destruction (Kispiox LRMP Anonymous, 1996). The goal of the Shelagyote River bull trout studies were to:

1) confirm the presence of bull trout within the watershed; and, 2) identify critical bull trout habitat areas (eg. spawning, staging and rearing)

requiring special protection measures. In order to achieve goal 2) above, the following objectives were also identified:

i. describe bull trout run-timing attributes; ii. define bull trout life history attributes, such as, age and length-of-maturity,

age and size class distribution, sex ratios; and iii. determine spatial and temporal patterns of bull trout habitat use within the

Shelagyote River watershed.

A 1:20,000 reconnaissance fish and fish habitat inventory (1:20K FFHI) was also undertaken concurrent with the second year of the adult bull trout studies by Triton Environmental of Terrace, under contract to Skeena Cellulose Inc. (SCI). The majority of the field sampling was completed for this project and information sharing existed between projects to assist in the achievement of this project’s stated goals. Unfortunately, SCI went into receivership and was unable to pay Triton for works completed or for any future work. Therefore, the information collected under the 1:20k FFHI was unavailable at the time of report preparation. The 1:20k FFHI would have provided information regarding tributaries and reaches where bull trout juveniles were captured and the associated proximal habitat. This would have provided strong evidence of potential bull trout natal streams.


Figure 1: Location of the Shelagyote River watershed in the Skeena Region.

2.0 Methods

2.1 Fish Sampling

2.1.1 Timing & Location Bull trout sampling within the Shelagyote River watershed spanned a period of two seasons, beginning April 26, 2000 and ending Nov. 8, 2001. Within that period, the Shelagyote was sampled on six separate occasions. A Bell 206 Jet Ranger helicopter was used to access the area on each trip. Sampling events on April and September 26, 2001 were summarized by Beere (2000) and Giroux (2000) respectively. Results from all sampling events are incorporated in this report. Mainstem river and deep tributary pools were the primary habitats sampled for adult bull trout. Sites in the lower reaches of the Shelagyote mainstem were sampled repeatedly (Fig. 2).


Figure 2: Sample site locations within the Shelagyote River watershed, April 26, 2000 – Nov. 8, 2001.

2.1.2 Fish Capture and Handling Adult bull trout sampling was conducted using conventional angling techniques in the Shelagyote River mainstem and larger tributaries (Fig. 2). Captured bull trout were placed in a water bath and anaethsitized with a 1:10 parts clove oil/ethanol solution at a concentration of 1:4000, clove oil solution to water. Once bull trout had displayed a loss of equilibrium, they were measured for fork length, Floy T-anchor tagged, and had a 2 cm section of the leading edge of one pectoral fin ray removed. Pectoral fin ray clips were aged by North/South Consultants, Winnipeg, MB. A sub-sample of bull trout adipose fin tissue samples was submitted to M. Bahr of UNBC, Biology Department, for analysis and inclusion as an out-group of bull trout, in her M.Sc. thesis on Morice River bull trout (Bahr, in prep.).

2.1.3 Fish Gender Determination Fish gender was determined through visual inspection of head shape and typical salmonid sexual morphology associated with spawning (e.g. existence of kipe, dramatic colour and pronounced ovipositor) or recorded as unknown. Bull trout were identified as males when the anterior portion of the head appeared elongated when viewed dorsally, bright orange colouration existed on the ventral side, and if the presence of a kipe was evident. Bull trout were classed as females when kipe and snout elongation was not present and colouration on the ventral side was not present (Fig. 3). Individual bull trout were also compressed


gently on their ventral side, anterior to the vent to examine for the existence of and the condition of the ovipositor or the presence of milt or eggs.

Figure 3: Example of dorsal and lateral view of mature female bull trout head.

2.1.4 Fish Maturity Determination Fish maturity was also observed and recorded for each fish handled. Fish were classed as being either maturing, ripe, or kelt (post spawn condition). Fish which did not have any signs of sexual dimorphism as a result of spawning were classed as maturing. Bull trout with an orange ventral surface, dark green head with a kipe (males only), bright red lateral spots and had milt or eggs present when ventrally compressed, and did not have evidence of fin abrasion or scratches on their posterior end were classed as ripe. Bull trout were classed as being a kelt when ventral and lateral spot colouring was faded; a kipe and darkened head colour were present, but less developed; and, when ventrally compressed, clear liquid was present for males, and only the ovipositor protruded for females (Fig. 4). Also typical for bull trout male kelts was the presence of dorsal/lateral scratches on the posterior end of the fish. It is speculated that the scratch marks are the result of male to male confrontations while defending spawning redds or paired females.

Figure 4: Male bull trout kelt (63.5 cm fork length). Note dark green head, developed kipe, faded orange ventral colouring and lateral red spots.


2.2 Habitat Assessment

2.2.1 Stream Habitat Inspections Fisheries technicians from Triton Environmental Ltd., Terrace BC, who were working on the 1:20,000 reconnaissance FFHI in the Shelagyote River watershed were hired to conduct stream inspections in stream reaches known to: 1) contain juvenile bull trout; 2) have access to the mainstem Shelagyote River; and, 3) contained habitat suitable for spawning (Fig. 3). Resource Inventory Committee (RIC), Field Data Inventory System (FDIS) FFHI site cards were filled out for each reach inspected. Inspections were conducted during periods when adult bull trout were suspected to be in tributary streams during spawning activity or migrations.

2.2.2 Water and Air Temperature Monitoring The Shelagyote mainstem at the confluence with the Babine, upstream of the Cayuse Jack Creek confluence; Babine mainstem, and a lake headed unnamed tributary were monitored for water temperatures from May 4, 2000 –to- November 8, 2001 using On-site Tidbit™ temperature data loggers (Fig. 5). Ambient air temperature was monitored at Shelagyote/Babine confluence and at Cayuse Jack Creek over the same time period using Tidbit data loggers. Tempeature data loggers were encased in 2” galvanized steel “T” pipe and secured to a tree using 1/8” aviation cable.

Figure 5: Location of temperature loggers (triangles) and stream reaches inspected (circles) to locate spawning bull trout or bull trout redds.


3.0 Results

3.1 Fish Sampling Over the two seasons of sampling, bull trout, steelhead (Oncorhynchus mykiss), rainbow trout (O. mykiss), and coho (O. kisutch) salmon were captured and handled throughout the Shelagyote River watershed including the Babine River at the Shelagyote confluence. Thirty-six bull trout, 10 steelhead and three coho were sampled for length (Table 1). Four coho, three rainbow trout (one sampled at site 3, 40 cm), one chinook salmon (O. tshawytscha; site 3, Aug. 20, 2001) and three steelhead were also captured, but released without being sampled for length.

Table 1: Summary of fish length (fork length) and age for bull trout only.

CO STLength Age Length Length

n 36 35 3 10Mean (+SE) 50.69 (+1.3) 8.2 (+0.3) 61.3 (+3.7) 63.68 (+3.9)

Min. 33 5 54 52Max 65 13 66 94

BT

Rainbow, steelhead, coho and chinook were caught exclusively in sites located in the lower 9km of the Shelagyote River, whereas bull trout were captured throughout the mainstem (Fig. 6). Sites 3 (n=16) and 630 (n=13) held the greatest number of total fish captured, whereas sites 3 (r=5) and 2 (r=4) had the greatest species richness (Fig. 7). Sites 626 and 621, located in upper watershed locations, both produced 2 and 5 bull trout respectively during the September 14, 2001 sampling event (Fig. 6 & 7). Bull trout were the only fish species captured in the latter two sites mentioned, as well as, site 1 and 629. Coho were the only species captured at site 7.


Figure 6: Catch locations for bull trout (BT), steelhead (ST), coho salmon (CO) and rainbow trout (RB) within the Shelagyote River watershed for all sampling events (April & Sept., 2000, August, September and November 2001).

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Figure 7: Summary of fish abundance and species richness, by site within the Shelagyote River watershed (CH – chinook, RB – rainbow trout, CO – coho, ST – steelhead, BT – bull trout).

3.2 Bull Trout Sampling

3.2.1 Length-at-Age The 38 bull trout captured in the Shelagyote River demonstrated a normal length frequency distribution (Fig. 8). Mean length for captured bull trout was 50.7 cm (SE±1.3); minimum length was 33 cm and the maximum length was 65 cm (Table 1). The mean age of bull trout captured was 8.2 yrs (± 0.3). The oldest bull trout sampled was 13 yrs, whereas the youngest bull trout was 5 yrs (Table 1).

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Figure 8: Length class frequency and mean age (± SE) for bull trout captured in the Shelagyote River watershed between March 2000 and November 2001.


The correlation between bull trout length and age was weak (r2=0.37), this is not surprising however, given the low sample size and the low variability of ages for the lower size classes (Fig. 8).

3.2.2 Maturity Shelagyote River bull trout appear to reach reproductive maturity by age six as 40 cm was the smallest fish captured to display externally recognizable maturity characteristics (Fig. 9). Bull trout in the 35-40 cm size class did not display any external maturity characteristics, even though this length-class were older on average than 55cm fish (Fig. 9). The age class for the 35-40 cm length class was elevated due to one of the two fish sampled recording an age of 11 at 40 cm, while the second at seven years old. Thirty-three percent of the 40-45 cm size class, with a mean age of six yrs old, were mature. Bull trout of the 45-50 cm length class also had a mean age of six years old and 50% of the fish captured were identified as being mature. Eighty-six percent of the 50 cm long, 8 year old bull trout were identified as being sexually mature (Fig. 9). External maturity characteristics were considered inconclusive for April sampling events.

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Figure 9: Percentage of bull trout captured in the Shelagyote River watershed identified as being mature presented by size class. Mean age of bull trout is also plotted on the second axis.

3.2.3 Run Timing & Gender Differences The bull trout captured in the Shelagyote demonstrated detectable maturity differences along a temporal gradient (Fig. 10). Bull trout sampled to August 20th, were primarily maturing (92%, n=10), with a small component being described as ripe (8%, n=1). Thirty-eight percent bull trout sampled on September 14th were classed as ripe (n=3) and 50% as kelts (n=4; Fig. 10). During late September and November sampling events kelts and maturing fish were sampled exclusively (Fig. 10). The discovery of ripe adults in August and kelts in mid-September indicates that the spawning period most likely occurs


between August 20th and September 14th. The majority of spawning appears to have been completed by September 26th. Pre-spawn bull trout were captured at various locations. However, sites 3, 621, 626 and 629 appear to be important rearing/staging areas. Sites 1, 3 and 630 provide migration habitat and may be utilized as possible over-wintering areas.

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Figure 10: Percent maturity of captured bull trout and number of bull trout captured on sampling events from April 26, 2000-to-Nov. 8, 2001 in the Shelagyote River watershed.

Female bull trout were captured with greater frequency than males up to and including the September 14th sampling events (Fig. 11). Males were captured with two-times greater frequency during sampling events following September 26th (2.6:1, 2:1, Fig. 11). It is worth noting however, that only one male bull trout was captured in the Shelagyote on November 8th, whereas the others (1♂ &1♀) were captured in the Babine at the Babine/Shelagyote confluence. Therefore, bull trout of both sexes are located in the lower reaches of the Shelagyote River in similar concentrations from August to early September, whereas in late August, males dominated the sample in the Shelagyote (Fig. 11). The low sample size observed during the November sampling period (n=1 in Shelagyote, n=2 in Babine/Shelagyote confluence) limits gender interpretations; however, it does indicate low densities in the Shelagyote River during periods of low water temperature (0.5oC) and discharge.


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Figure 11: Male:female sex ratio for bull trout captured in the Shelagyote River between August 20 and Nov. 8, 2001. 1:1 line represents equal male:female ratio. Numbers presented in bars represent number of fish.

3.3 Habitat Assessment

3.3.1 Water and Air Temperatures Mean water temperature for the Shelagyote River at Babine and Cayuse Jack Cr. from May 5 to Nov. 8th, 2001 was 5.5oC and 4.6oC respectively (Table 2). The water temperature of the Shelagyote River at the Shelagyote/Babine River confluence (mean temp. 5.5oC) was significantly warmer than temperatures measured at the Cayuse Jack Cr. confluence (4.64oC; t = 2.57, p=0.001). A similar pattern was observed for ambient air temperatures sampled at the same locations; however differences between locations were greater (Table 2). Table 2: Summary of water and air temperatures (degrees Celsius) recorded hourly at stations located in the Shelagyote River at the Babine River confluence and Cayuse Jack Cr. confluence.

Mean Max Min SE nShelagyote River @ Babine confluence Ambient Air (celcius) 10.5 29.7 -4.6 0.09 3897

Water Temperature (celcius) 5.5 12.3 0 0.04 4515

Shelagyote River @ Cayuse Jack Cr. Ambient Air (celcius) 6.1 23.5 -2.2 0.07 4515

Water Temperature (celcius) 4.6 12 -0.16 0.04 4515

Hourly water temperatures of the Shelagyote River ranged between 0oC and 12.3oC. The peak mean daily water temperature occurred on August 13, 2001 (9.3oC). The daily mean maximum air temperature was recorded on July 22 (19.5oC), followed by a second warm period that peaked on August 14th, 2001. Water and air temperatures were averaged over a 5-day period to present general trends in temperature (Fig. 12).


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Figure 12: Five-day running mean water temperature data (degrees Celsius) for Shelagyote River at Cayuse Jack Cr. (grey line) and at the Babine River confluence (black line), as well as, air temperature at the Shelagyote Babine River confluence (dashed line) from May 5, to November 8, 2001.

The temperature loggers launched in the Babine River upstream of the Shelagyote River were removed by recreational anglers on October 14, 2001. The loggers launched in the Babine River and the unnamed tributary appear to have become dewatered on July 14th and July 9th, 2001, respectively. However, sufficient data was recorded to demonstrate that the unnamed lake headed tributary and Babine River water temperatures were much greater than those recorded in the Shelagyote for the spring and early summer periods (Fig. 13).

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Figure 13: Five-day running mean water temperature (degrees Celsius) for the Shelagyote (black line), Babine River (dark grey line) and unnamed lake headed tributary (light grey line) to the Shelagyote River beginning on May 4, and ending July 9th (unnamed trib) and July 16th (Babine), 2001.


3.3.2 Spawning Habitat Inspections Four stream reaches were inspected for spawning bull trout or their redds (Fig. 5). Adult bull trout were not observed nor were redds detected by field crews. Site physical characteristics are summarized in Table 3. Table 3: Summary of physical parameters measured at representative sites within reaches waked by field crews during suspected spawning site inspections.

Mean Mean MeanStream Name Site No. UTM Channel

Width (m)Wetted

Width (m)Residual

Pool Depth Mean

Gradient (%)Dominant Sub-dominant D(cm) Temp.

(degrees C)Conductivity

(usms)Spawning Hab. Rank

Barger Cr. Reach 1 9.608021.6195039 19.7 5.8 1.2 2.8 cobble gravel 25 5 50 moderateCayuse Jack Cr. Reach 1 9.608822.6180135 8.3 4.8 1.1 6.8 boulder cobble 40 5 50 lowUnnamed 620 9.604773.6198675 9.0 7.5 0.7 3.5 cobble boulder 40 7 20 moderateUnnamed 625 9.607463.6184555 16.4 6.3 0.5 4.5 cobble boulder 50 9 80 low

Substrate

4.0 Discussion

4.1 Bull Trout Run-Timing & Movement It is apparent from the results that the Shelagyote bull trout population is a fluvial life history form. Shelagyote River bull trout appear to over-winter and rear in the Babine River and migrate into the Shelagyote River watershed to spawn in its tributary streams. A 53 cm male bull trout kelt was caught and tagged in the Shelagyote River on September 26, 2000. It was re-captured in the Babine River by an angler on October 16, 2000 (Len Vanderstar, pers. comm.). This demonstrates that Shelagyote bull trout migrate to the Babine following spawning, likely to over-winter and rear. Other evidence of bull trout movement out of the Shelagyote following spawning exists in the low catch rates of bull trout in the lower reaches during spring and late fall sampling events (Fig. 10). Bahr (2000), Swanberg (1997) and Burrows et al. (1999) also reported a similar pattern of bull trout immigration from large 7th order rivers to lower order natal tributary streams. Bull trout may move out of the Shelagyote for increased feeding opportunities, predator avoidance and a preference for warmer winter water temperatures, such as those found in the Babine River (Fig. 13). There is insufficient evidence to precisely predict when the bull trout immigration from the Babine to the Shelagyote begins. However, based on the catch abundance and maturity observations conducted during sampling events (Fig. 10), it could be speculated that the majority of the migrating bull trout that intend to spawn have moved into the Shelagyote by mid to late-August (Fig. 14). The catch results are corroborated by others studying the movements of fluvial bull trout and the noted relationships between bull trout movements and water temperature (Fraley & Shepard 1989, Schill et al. 1994, Swanberg 1999). Swanberg (1999) was able to demonstrate a significant relationship existed between pre-spawn bull trout migrations and increases in water temperatures


and that movements were initiated by temporary peaks in water temperature. Schill et al. (1998) also encountered the majority of upstream migrants shortly after water temperatures rose above 4oC. Bahr (2000) also observed bull trout immigrations to lower order natal tributaries after the water temperature rose to 6oC, following an increase in temperature from 4oC. Therefore, the increase in Shelagyote River water temperature above 4oC during the first week in June may trigger migratory movements of bull trout into the Shelagyote.

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Shelagyote at Cayuse Jack Cr.Shelagyote at Babine confluence Ambient Air at Shelagyote/Babine

spaw ningimmigration

over-w intering

emigration &over-w intering

staging

Figure 14: Approximate annual life history stages of adult Shelagyote River bull trout in relation to Shelagyote River five day running mean water and ambient air temperature (degrees Celcius).

With the data available, it is difficult to precisely identify the peak spawning period in the Shelagyote River; however, based on bull trout condition and abundance during sampling events (Fig. 10), Shelagyote River bull trout spawning appears to begin in late August and is completed by the end of September. This is also supported by others working in BC and the US Pacific Northwest. Radio tracking bull trout in the Morice River watershed, Bahr (2000) reported peak spawning times to be August 26th to September 15th. Burrows et al. (1999) also report emigration of Halfway River bull trout kelts to occur in late September/early October. The suggested spawning and migration patterns for Shelagyote River bull trout are also supported by others who have examined the relationship between movement and water temperature. In their review of available literature on bull trout life history and its relationship to water temperature, Buchanan and Gregory (1999) place migration periods from June to October and spawning from July to October. McPhail and Murray (1979) reported 9oC as the threshold temperature for bull trout spawning. Schill et al. (1994) and Reihle (1993) also reported


spawning behaviour was observed by bull trout only after water temperatures dropped below 10oC and 9oC respectively. In Bahr’s (2000) preliminary results, a qualitative analysis indicates that spawning began in the Morice River tributaries following a decline in peak seasonal water temperatures. Transferring this to the Shelagyote River, spawning would be placed at approximately August 20th. Shelagyote bull trout also demonstrated gender specific movement patterns consistent with other repeat spawning freshwater species. Beere (in prep) noted that steelhead females departed soon after spawning was completed and well in advance of males. Although the Shelagyote bull trout sample size is small, Shelagyote bull trout appeared to demonstrate a similar pattern (Fig. 11). The male to female ratio is closer to one prior to spawning when compared to post spawning gender ratios. Male bull trout appear to prolong their efforts to spawn with as many females as possible, whereas once females have spawned, they no longer have the ability to spawn again and quickly emigrate to post spawn recovery and winter feeding/rearing areas.

4.2 Spawning Locations Specific spawning locations for bull trout were not directly observed nor confirmed during the course of this project. The tributary stream reaches where juvenile bull trout were captured remain as the most likely locations where bull trout spawn in the Shelagyote River watershed. The stream walks conducted in September by Triton staff, were conducted in streams where juvenile bull trout were captured. However, ground based observations for spawning bull trout or their redds was inconclusive. Spawning bull trout and their redds can be difficult to identify, especially in larger streams or by staff unfamiliar with conducting redd or spawner surveys. Furthermore, bull trout densities and their subsequent redds could have been low, contributing further to the difficulty in redd or spawning location identification. Mainstem spawning may occur; however, there is little evidence to support or validate this presumption. Juvenile sampling did not occur in the mainstem, nor were spawning adults or redds observed. Suitable mainstem habitat was not assessed in detail. However, it is likely that substrates and flows conducive to bull trout spawning do exist in the mainstem Shelagyote River. Bahr (2000) could not confirm mainstem spawning in the Morice River, as many of her radio tagged bull trout did not migrate to low order streams during the spawning period. McPhail and Baxter (1994) summarize bull trout spawning preferences and discuss the existence of mainstem spawning, but emphasise the inherent difficulties in observing spawning fish or their redds in large systems. They also discuss an apparent preference for bull trout to spawn in small streams.

4.3 Growth and Maturity Growth in terms of a length-to-weight relationship was not assessed in this project. However, length-at-age does provide some insights into the growth of


the Shelagyote bull trout. The smallest bull trout captured was 33 cm and was reported to be 5 years old. This is slightly older than the growth and emigration pattern discussed by McPhail and Baxter (1994), where they state that most stream rearing bull trout leave their natal streams at age 4+. This could be expected as the majority of the bull trout populations discussed in their review were from areas near the 49th parallel, which would have longer growing seasons compared to the Shelagyote River located at 55oN. Shelagyote River bull trout appear to reach maturity by age 6, as none of the bull trout aged to five years possessed mature characteristics. McPhail and Baxter (1994) provide age 4+ as the age of maturity for fluvial bull trout populations that exceed the size of 400 mm. As the Shelagyote River is situated 6 nautical miles north of the source of the McPhail and Baxter (1994) references, it is conceivable that shorter growing seasons may prolong the maturity period by greater than one year.

4.4 Habitat and Temperature Habitat parameters described by field crews indicate that adequate juvenile rearing habitat was present in most reaches surveyed, whereas only two of the four reaches were considered moderate in spawning quality (Table 3). Water temperature, substrate and gradient parameters measured do not exclude any one of the sites inspected for spawning bull trout. It is possible that bull trout spawning areas were further upstream to the areas walked by ground crews. Bustard (1997) demonstrated that bull trout juveniles are often found well downstream to spawning areas in the Thautil River watershed and suggested that they migrate downstream as they age. It is also possible that crews were in spawning areas but were unable to detect spawning bull trout due to low bull trout densities or the use of cover to avoid detection. Bull trout redds may also be difficult to detect as there was very little periphyton attached to stream substrates. In addition, water clarity was not optimal.

5.0 Conclusions Low sample sizes hinder the power of the conclusions drawn as a result of this study. Despite this, compelling patterns exist for some aspects of the study thereby permitting the following conclusions. A fluvial population of bull trout exists in the Shelagyote River and evidence indicates that small numbers of the char occupy the lower mainstem reaches throughout the year. Over-wintering conditions within the Shelagyote appear to be marginal due to low winter water temperatures compared to Babine River. Critical rearing and staging areas were identified in the lower 9km of the Shelagyote River and at the pools located at the confluence of suspected natal tributaries with the Shelagyote River. Attempts to


identify spawning areas were inconclusive and spawning reaches remain largely unknown. However, in conjunction with the 1:20,000 reconnaissance fish and fish habitat inventory conducted by Triton Environmental Consultants for Skeena Cellulose Inc., suspected bull trout natal tributaries have been identified The majority of Shelagyote bull trout appear to over-winter in the Babine River and migrate into the Shelagyote beginning in early June when the Shelagyote River water temperature increases above 4oC. Bull trout stage and ripen prior to spawning in early August or at the onset of a decline in water temperature. Spawning appears to begin in late August/early September once temperatures drop and remain below 10-9oC. Bull trout emigrated from the Shelagyote River following spawning by the end of September/early October once water temperatures drop below 6oC. Shelagyote River bull trout were on average 50.7(±1.3) cm long and char in excess of 65cm in length were not captured. Shelagyote bull trout appeared to reach maturity by age six, at a length of approximately 45cm (fork length). Prior to spawning, male to female sex ratios approached equal numbers. Up to a month following spawning, males were more abundant in the Shelagyote River.

6.0 Recommendations

1. Road access to the Shelagyote River shall be limited to greater than 1km from the lower 9km of the Shelagyote River and 1km from lower reaches of identified bull trout natal tributaries. The tributary reaches of concern will be made clear upon release of the Triton 1:20K FFHI data. Access restrictions of 1km will limit foot access to a one hour hike. Low bull trout densities and relatively small fish (maximum length of 65cm), may limit angler effort. However, angler harvest during spawning migration periods could have negative impacts on the local bull trout population.

2. Data supporting special angling regulations for bull trout in the Shelagyote River is not compelling in this instance. However, interpretation of the available results indicate that bull trout congregate in the lower reaches prior to and post-spawning. Male bull trout are more vulnerable to angler harvest than females. There also does not appear to be a high abundance of bull trout in the Shelagyote River. The significance of the Shelagyote River as a natal watershed for the larger Babine River bull trout population remains largely unknown. With increased access and subsequent increase angler harvest pressure, conservation regulations may be considered. Non-retention for Shelagyote bull trout for July 1 – to – September 30 would offer the greatest protection for the population while, permitting some angler harvest opportunity.

3. The Shelagyote River watershed has been identified as a natal watershed to bull trout in the Babine watershed. As mentioned above in


Recommendation 2, it is unclear of its significance to the bull trout population for the Babine and middle Skeena. A study involving the capture and radio-tagging of lower and middle Babine River bull trout would contribute greatly towards addressing this information deficiency.

4. Identification of bull trout spawning areas remains undetermined. Radio telemetry of Shelagyote River bull trout remains as the preferred technique for identification of spawning areas with the least risk of failure.

5. Temperature monitoring of suspected natal tributaries would contribute towards increasing the understanding of the relationship between bull trout movement, spawning and water temperature.

6. Analysis of habitat productive capability of natal tributaries would assist in understanding growth rates of higher latitude juvenile bull trout.


7.0 References Anonymous. 1996. Kispiox Land and Resource Management Plan. Prepared

by Kispiox Land and Resource Planning Team. 70pp. Bahr, M. 2001. Examination of bull trout (Salvelinus confluentus) life history

strategies in the Morice River watershed. Unpublished Interim Report. Biology Program, University of Northern British Columbia, Prince George BC.

Bahr, M. in preparation. Examination of bull trout (Salvelinus confluentus) life

history strategies in the Morice River watershed. M.Sc. Thesis, Biology Program, University of Northern British Columbia, Prince George BC.

Beere, M.C. 2000. Trip Report, Shelagyote River, April 26, 2000. Memo to

Skeena Region, BC Ministry of Water, Land and Air Protection file: 34250-20-Fish-special stocks/char/bull trout; Shelagyote (Babine R. watershed) River file, Smithers BC.

Beere, M.C. in preparation. Over-wintering mortality of upper Sustut River summer run steelhead trout radio tagged in the fall of 1998. Skeena Fisheries Report SK #?. BC Min. of Water, Land and Air Protection, Smithers, BC.

Buchanan, D.V. & S.V. Gregory. 1997. Development of water temperature

standards to protect and restore habitat for bull trout and other cold water species in Oregon. In: Mackay, W.C., M.K. Brewin and M. Monita, 1997. Friends of the Bull Trout Conference Proceedings:119-126.

Burrows, J, T. Euchner, & N. Baccante. 2001. Bull trout Movement Patterns:

Halfway River and Peace River Progress. In: Brewin, M.K., A.J. Paul, and M. Monita, 2001. Bull trout II Conference Proceedings:153-157.

Bustard, D. 1997. Reconnaissance inventory of the Thautil River. Report

completed for Houston Forest Products, Houston BC and the BC Ministry of Environment. Unpublished manuscript.

Fillier, Darren. Personal communication. Habitat Section Biologist, Skeena

Region, Ministry of Water, Land and Air Protection, Smithers, BC. Fraley, J.J. and B.B. Shepard. 1989. Life history, ecology and population status

of migratory bull trout (Salvelinus confluentus) in the Flathead Lake rive system, Montana. Northwest Science 63(4):133-143.


Giroux, P.A. 2000. Trip Report, Shelagyote River, September 26, 2000. Memo to: Skeena Region, BC Ministry of Water, Land and Air Protection file: 34560-27 BAB/SHELAG file, Smithers, BC.

Harris, Jason. 2001. Personal Communication. Fisheries Technician, Triton

Environmental Consultants, Terrace, BC. Goetz, F.A. 1989. Biology of the bull trout Salvelinus confluentus, a literature

review. US Department of Agriculture, Forest Service, Willamette National Forest, Eugene, Oregon. 53p.

McPhail, J.D. and J. Baxter. 1994. A review of bull trout (Salvelinus confluentus)

life history and habitat use in relation to compensation and improvement opportunities. Department of Zoology and Fisheries Center, University of BC, Vancouver, BC. Unpublished manuscript.

McPhail, J.D. and C.B. Murray. 1979. The early life-history and ecology of Dolly

Varden (Salvelinus malma) in the Upper Arrow Lakes. University of BC Department of Zoology and Institute of Animal Resources, Vancouver BC.

Riehle, M.D. 1993. Metolius Basin water resources monitoring, progress report

1988-1992. U.S. Forest Service. Intermountain Research Station, Boise Idaho.

Schill, D., R. Thurow, & P. Kline. 1994. Seasonal movements and spawning

mortality of fluvial bull trout in Rapid River, Idaho. Job Performance Report, Wild Trout Evaluations. IDFG 94-13

Stewart, Robert. Personal communication. Former Forest Ecosystem Specialist,

Kispiox Forest District, Habitat Section, Skeena Region, Ministry of Water, Land and Air Protection, Hazelton, BC.

Swanberg, T.R. 1997. Movements of and habitat use by fluvial bull trout in the

Blackfoot River, Montana. American Fisheries Society 126:735-746. Vanderstar, Len. Personal communication. Habitat Section Biologist, Skeena

Region, Ministry of Water, Land and Air Protection, Smithers, BC.


8.0 Appendicies

8.1 Appendix ‘1’: Catch and site data

Site Zone Easting Northing Species Date BT # Floy # Floy Colour Length Sex Age Maturity Co1 9 617662 6167499 BT 26-Sep-00 1 1875 white 44 F 10 Maturing1 9 617662 6167499 BT 26-Sep-00 2 1874 white 49 M 10 kelt1 9 617662 6167499 BT 26-Sep-00 3 1873 white 63.5 M 12 kelt ph1 9 617662 6167499 BT 26-Sep-00 4 1872 white 54 ? 9 kelt low1 9 617662 6167499 BT 26-Sep-00 5 1871 white 55 F 8 kelt1 9 617662 6167499 BT 26-Sep-00 6 1870 white 41 F 8 kelt2 9 615349 6170802 BT 26-Sep-00 1 1877 white 59 M 11 kelt ph2 9 615349 6170802 BT 26-Sep-00 2 1879 white 60 M 11 kelt2 9 615349 6170802 BT 26-Sep-00 3 1878 white 36 ? 7 Maturing2 9 615349 6170802 BT 26-Sep-00 4 no floy 33 ? 6 Maturing2 9 615349 6170802 SST 26-Sep-00 n/a n/a n/s n/s n/s2 9 615349 6170802 RB 26-Sep-00 n/a n/a n/s n/s n/s2 9 615349 6170802 CO 26-Sep-00 n/a n/a n/s n/s n/s 4 3 9 614352 6171726 BT 26-Sep-00 1 1880 white 52 M 9 kelt3 9 614352 6171726 BT 26-Sep-00 2 1881 white 62 M 12 kelt ph3 9 614352 6171726 BT 26-Sep-00 3 1883 white 53 M 8 kelt re3 9 614352 6171726 BT 26-Sep-00 4 1884 white 42 M 6 kelt ph3 9 614352 6171726 BT 26-Sep-00 n/a no floy 51 M n/a ca3 9 614352 6171726 SST 26-Sep-00 n/a n/a n/s n/s n/s 3 3 9 614352 6171726 RB 26-Sep-00 n/a n/a n/s n/s n/s8 9 614026 6172446 NFC 26-Sep-00 n/a n/a n/a n/a n/a sit5 9 611722 6175542 NFC 26-Sep-00 n/a n/a n/a n/a n/a6 9 609832 6180653 NFC 26-Sep-00 n/a n/a n/a n/a n/a 3

630 9 618585 6165291 BT 14-Sep-01 62006 14486 white 53 F 11 kelt629 9 613991 6172469 BT 14-Sep-01 62005 14485 white 48 F 8 ripe621 9 605060 6198480 BT 14-Sep-01 62000 14480 white 53 M 8 ripe626 9 607549 6184502 BT 14-Sep-01 62001 14481 white 56 F 7629 9 613991 6172469 BT 14-Sep-01 62004 14484 white 65 M 11 kelt629 9 613991 6172469 BT 14-Sep-01 62003 14483 white 57 F 8 kelt626 9 607549 6184502 BT 14-Sep-01 62002 14482 white 52 F 7 ripe

3 9 614352 6171726 BT 20-Aug-01 62 42 F 6 Maturing629 9 613991 6172469 BT 20-Aug-01 71000 41 F 5 Maturing

3 9 614352 6171726 BT 14-Sep-01 4 10225 orange 59.5 M 8 kelt sit630 9 618585 6165291 BT 20-Aug-01 71002 48.5 M 6 Maturing630 9 618585 6165291 BT 20-Aug-01 71003 53 M 8 Maturing630 9 618585 6165291 BT 20-Aug-01 71001 47 F 5 Maturing621 9 605060 6198480 BT 20-Aug-01 14479 59 F 13 Maturing621 9 605060 6198480 BT 20-Aug-01 14477 48 M 5 Maturing

3 9 614352 6171726 BT 20-Aug-01 61 44.5 ? 5 Maturing621 9 605060 6198480 BT 20-Aug-01 14476 50 F 7 ripe621 9 605060 6198480 BT 20-Aug-01 14474 40 M 11 Maturing630 9 618585 6165291 BT 08-Nov-01 1 10226 orange 49 F 6630 9 618585 6165291 BT 08-Nov-01 2 10227 orange 46 M 5 kelt

1 9 617662 6167499 BT 08-Nov-01 3 10228 orange 59 M 10 kelt630 9 618585 6165291 ST 08-Nov-01 54.8 F n/a

3 9 614352 6171726 ST 08-Nov-01 76 F n/a630 9 618585 6165291 ST 08-Nov-01 52 n/a630 9 618585 6165291 ST 08-Nov-01 94 M n/a630 9 618585 6165291 ST 08-Nov-01 59 M n/a630 9 618585 6165291 ST 08-Nov-01 63 M n/a630 9 618585 6165291 ST 08-Nov-01 63 M n/a630 9 618585 6165291 ST 08-Nov-01 59 F n/a

3 9 614352 6171726 ST 08-Nov-01 54 F n/a3 9 614352 6171726 ST 08-Nov-01 62 M n/a3 9 614352 6171726 CO 08-Nov-01 54 M n/a3 9 614352 6171726 RB 14-Sep-01 40 n/a7 9 618289 6166820 CO 14-Sep-01 66 M n/a sit7 9 618289 6166820 CO 14-Sep-01 64 M n/a sit

620 9 604773 6198675 NFC 14-Sep-01 n/a622 9 605165 6158391 NFC 14-Sep-01 n/a623 9 605241 6198075 NFC 14-Sep-01 n/a624 9 605300 6197929 NFC 14-Sep-01 n/a627 9 607729 6183691 NFC 14-Sep-01 n/a628 9 613840 6172687 NFC 14-Sep-01 n/a631 9 607355 6172687 NFC 14-Sep-01 n/a


8.2 Appendix ‘2’: Beere, 2000 and Giroux, 2000 Trip Reports To: File

Date: File:

July 4, 2002 34250-20-Fish-Special Stocks/Char/Bull Trout; Shelagyote (Babine R. watershed) River file

Re: Trip Report, Shelagyote River, April 26, 2000 On Wednesday, April 26, Fisheries Branch staff Dana Atagi, Paul Giroux and myself flew (Canadian Helicopters, Tom Brooks, pilot) to the Shelagyote River. The object of the trip was to attempt to radio tag bulltrout (Salvelinus confluentus) to identify staging, spawning and rearing areas. Incidental to this primary objective, we attempted to collect reconnaissance information regarding an unnamed lake and stream tributary to the Shelagyote, and to review the proposed site of a logging road bridge crossing. Bull Trout Sampling Conventional angling gear was deployed to capture bulltrout in the mainstem Shelagyote River at select, deeper water pools (Figure 1.) throughout the lower 20 kilometers of the river (6 sites in total; Figure 2). The water temperature of the Shelagyote River, approximately 3 km upstream of the Shelagyote-Babine confluence was 2o C at 10:30 hours and increased to 4oC at 16:00hrs. The visibility of the Shelagyote was approximately 0.5 m.

Figure 1: Site 1, Shelagyote River where over-wintering steelhead and bulltrout were found.

Shelagyote River bull trout life history Page 23

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26_04_2000gis.shp

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BC Min. Env. Lands, ParksSkeena RegionMay 3, 2000

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2 0 2 Kilometers1:130,000

Shelagyote River: Sample Locations

Site 5

Site 6

Site 1Site 2

Site 3Site 4

Babine River

Gunanoot Lake

Shelagyote R.

Figure 2: Sample locations along the lower reaches of the mainstem Shelagyote River.


Figure 3: 51 cm bulltrout captured at Site 6, Shelagyote River. As only two bulltrout were captured (~30 cm and 51 cm), and only the larger of sufficient size to implant a radio transmitter, we chose not to radio tag the single fish due to the prohibitive cost of tracking a single individual.

Figure 4: Scale sample collection, 74 cm female steelhead, Shelagyote River.


Of significance was the presence of over-wintering steelhead in the Shelagyote River. Six steelhead (64 cm to 78 cm) were captured in the Shelagyote and at Shelagyote-Babine confluence (Figures 2 & 4). Previously, it was assumed that Shelagyote steelhead over-wintered in the mainstem Babine River and then entered the tributary to spawn in the spring, once water temperatures had increased. Although it is assumed that this does occur, the fact that steelhead were found in the Shelagyote at water temperatures as low as 2oC indicates that they were likely over-wintering in the Shelagyote. This makes them increasingly vulnerable with increased human access and activity. Steelhead captured were measured, scales were taken for aging and a small amount of adipose tissue was taken for genetic archival and future analysis. Results are presented in Table 1. Table 1: Summary of sampling results

Lake Reconnaissance The unnamed lake in question was ice covered at the time of survey (Figures 5 & 6). Numerous ungulate tracks were seen along the shoreline of the lake. The outlet stream had some high gradient sections, which appeared to prevent upstream migration from the Shelagyote, but not downstream emigration from the lake to the Shelagyote. A number of red trees (presumably beetle kill) were viewed proximate to the lake. An inventory of the lake conducted by Joe DeGisi and Associates (1997), found the lake to be barren of fish and very shallow. DeGisi speculated that high gradient sections in the lower reaches of the outlet were the cause for the lake being barren of fish.

SITE_NO. LOCATION ZONE EASTING NORTHING FISH Length cm Sex DNA # Comments1 3.5 km u/s 9 617366 6167590 BT, ST 35, 74 M 1 BT not sampled2 2.5 km u/s 9 618038 6166920 ST 74 M 23 1.9 km u/s 9 618327 6166582 ST 74 F 34 Babine Confluence 9 618570 6165299 ST 57, 76, M 4, 55 1 km u/s Cayuse 9 610528 6179616 NFC6 9.8 km u/s 9 614274 6171739 BT, ST 51, 74 M 6, 7


Figure 5: Unnamed lake tributary to the Shelagyote River. The outlet tributary flows

generally eastward to join the Shelagyote River approximately 3 km upsteam of the Shelagyote-Babine river confluence.

Figure 6: Outlet of the unnamed lake noted above. Numerous moose tracks were noted

in this area. Shelagyote River Bridge Crossing


The area of the proposed bridge crossing of the Shelagyote was reviewed. The crossing is a small distance upstream of a potential over-wintering pool, making fish present vulnerable to capture. A black bear sow with two, two-year old cubs was observed immediately downstream of the proposed bridge crossing location. A moose was observed a small distance upstream of the bridge site. Moose and wolf tracks were common along the Shelagyote mainstem, including a large number of juvenile moose tracks. Mark Beere A/Senior Fisheries Biologist Skeena Region cc: Darren Fillier, FES, New Hazelton Paul Giroux, Fisheries Inventory Specialist, Smithers Dana Atagi, A/Fisheries Section Head, Smithers


To: File

Date: File:

January 24, 2001 34560-27 BAB/SHELAG

Re: Trip Report, Shelagyote River, September 26, 2000 On September 26, Fisheries Branch staff: Dana Atagi, Paul Giroux, Sig Hatlevik and Conservation Officer, Kevin Nixon flew (Canadian Helicopters, Bob Garnum, pilot) to the Shelagyote River with the following objectives: 1) to capture adult bull trout (Salvelinus confluentus) and confirm their presence and spawning activity within the Shelagyote watershed; 2) collect basic life history information (size, age and maturity) of the population; 3) obtain information on run-timing, spawning and migration; and, 4) identify potential mainstem rearing, staging or over-wintering habitats. Bull Trout Sampling Conventional angling gear was deployed to capture bull trout in the mainstem Shelagyote River at selected pools throughout the lower and mid-reaches of the river (Figure 1). Captured bull trout were placed in a water bath and aneathsitized with a clove oil/ethanol solution of 1:10 parts at a concentration of 1:4000, of clove oil solution to water (Soto & Burhanuddin, 1995). Bull trout were measured for fork-length, Floy tagged and had a pectoral and adipose fin clip removed. Pectoral fin clips were aged by North South consultants, Winnipeg, MB, whereas adipose fin clips will be analyzed as part of the Morice River bull trout study (M. Bahr, UNBC). Fish gender was determined using head shape and sexual morphology associated with spawning, or recorded as unidentified. Maturity was estimated by visual inspection of fish colouring and condition. Following processing, bull trout were held in recovery tubes up to 20 minutes in the river and released after recovery was evident. The water temperature of the Shelagyote River, approximately 3 km upstream of the Babine confluence was 8o C at 10:30 hours. The visibility of the Shelagyote was approximately 0.75 m. Results Fourteen bull trout were captured during the course of the day. Bull trout char were primarily concentrated in three pools sampled in the lower reaches of the main-stem Shelagyote River (sites 1, 2 & 3 of Figures 1 & 2). Fish were not captured in the remaining sites. Suitable staging habitat was identified further upstream near site 6 near the confluence of a third-order tributary. Mean bull trout fork length (fl) was 50.25 cm. Mean age was 9.07 yrs. All but three bull trout captured on this date were identified as being kelts (Table 1). The smallest kelt identified was a 41 cm fl, female, aged to 8 yrs. Figure 4 provides an example of the largest bull trout kelt captured, a male, aged to 12 yrs and 63.5 cm fl. Figure 4 also provides an example of the diagnostic features used to identify bull trout kelts: 1) faded orange colouring on the ventral side;


Figure 1: Sample locations along the lower reaches of the mainstem Shelagyote River. ● represents sample locations.

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Sample_locationgis.shp

# Sample_locationgis.shp

BC Min. Env. Lands, ParksSkeena Region

December 15, 2000

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2 0 2 Kilometers1:130,000

BT Sample Locations: Shelagyote River Watershed

23

4

5

6

1


Figure 2: Typical rearing habitat along Shelagyote River. Bull trout were captured at this site in both April (Beere, 2000) & September sampling events.

Table 1: Summary of bull trout captured on Shelagyote River, September 26, 2000

2) faded red spots on the lateral sides; 3) dark green head; and, 4) an enlarged kipe. The ventral side of male bull trout was also compressed to ascertain if milt was present. In the fish examined, clear liquid was expressed, indicating the fish were spent. Two fish were not sexed, as sexual dimorphism was not evident. It is suspected that these fish were still maturing or did not spawn earlier in the year. Adult coho salmon (Oncorhynchus kisutch), steelhead (O. mykiss) and rainbow trout (O. mykiss) were also captured at sites 2 & 3.

Site Zone Easting Northing Species n Range Mean Median M F ? Range Mean Median Maturing Kelt1 9 617662 6167499 BT 6 41 - 63.5 51.1 52.3 2 3 0 8 -12 10 10 1 52 9 615349 6170802 BT 4 33 - 59 47 46 2 0 2 6 -11 8.8 8.5 2 23 9 614352 6171726 BT 4 51 - 62 52 52.3 4 0 0 6 - 12 8.8 9 0 44 9 614026 6172446 NFC5 9 611722 6175542 NFC6 9 609832 6180653 NFC

UTM MaturitySexFork Length (cm) Age

Site 3


Figure 3: Length-frequency histogram for bull trout captured in the Shelagyote River, April 26 & September 26, 2000.

Figure 4: Bull trout male, kelt (63.5cm fork length), note dark green head, kipe on lower jaw and faded red spots and orange colouring on lateral and ventral side respectively.

Discussion Run-Timing & Movement The bull trout in the Shelagyote River system appear to have spawned previous to sampling. This is consistent with spawning timing demonstrated by Bahr (in prep.) in the Morice River watershed. Bahr (in prep) has reported that in the Morice watershed, bull trout moved into natal streams beginning in late June and reached spawning areas by mid-to-late August. Spawning likely occurred in late August -to- early September. Following spawning, bull trout in the Morice system returned to the mainstem from natal tributaries and were found to concentrate in association with spawning sockeye (O. nerka), pink (O. gorbuscha), and chinook (O. tshawytscha) salmon. Bull trout in the Morice system that did not move to natal streams or show signs of movement to spawning areas, remained in deep mainstem pools.

Bull Trout Length-Class FrequencyShelagyote River

0

1

2

3

4

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6

30-35 35-40 40-45 45-50 50-55 55-60 60-65 65-70 70+

Length-Class

Freq

uenc

y

n=15

faded orange colour

faded red spots

developed kipe

dark green head


Without similar detailed information for bull trout on the Shelgayote system as on the Morice, the behavior exhibited by Shelagyote bull trout can only be speculated upon. It can be concluded however, that: 1) it is likely that the majority of the season's spawning event had occurred in early September; and 2) a portion of the bull trout remain in the lower reaches of the Shelagyote immediately following spawning. One of the Floy-tagged bull trout (42 cm ♂, Floy # 1884) was re-captured by a recreational angler in the Babine River upstream of the Shelagyote River confluence October 16, 2000. This supports the speculation concluded as a result of the April 26, 2000 sampling, where one bull trout was captured, that some Shelagyote bull trout rear and likely over-winter in the Babine River mainstem. Shelagyote River Bull Trout Population The Shelagyote River contains the only recorded occurrences of bull trout in the lower Babine River watershed (BC Fisheries Warehouse & Regional files). There are recorded occurrences of bull trout within the Nilkitkwa River, Nicheskwa, Hanawald and Heal creeks (Triton 1997). However, these are captures of juvenile fish in upper watershed locations. Furthermore, as many of these samples are collected in upper headwater locations, it is not clear if these are resident or adfluvial populations. It is however, confirmed that the Shelagyote contains at least, adfluvial populations. It is suggested that the Shelagyote may be a significant natal system for the Babine River watershed and holds many watershed characteristics similar to the Gosnell watershed, a significant bull trout natal stream in the Morice watershed. Parameters of watershed area, aspect, total lake area, median and mean elevation, as well as anadromous fish species assemblages are similar between the two watersheds (Table 2). Whereas, the Shelagyote watershed contains three-times more glacial ice area compared to the Gosnell (Table 2). Table 2: Summary of Shelagyote River and Gosnell Creek watershed

characteristics. The other similarity between both systems is the lack of a large headwater lake. Although McPhail and Baxter (1994) do not discuss this in their review of bull trout life history and habitat use, it is a pattern worthy of consideration. It is speculated that bull trout utilize colder non-lake headed watersheds in order to avoid competition from more aggressive and faster growing anadromous fish species in their juvenile life stage. This behavior was observed by Johnson et al.

Watershed Watershed Area (ha)

Watershed Aspect

Total Lake Area (ha)

Mean lake area (ha)

Max. individual lake area (ha)

Mean Watershed Elev. (m)

Med. Elev. (m)

Min/Max Elev. (m)

Glacial Ice Area (ha)

Andromous Fish sp.

Shelagyote 58119.4 NNW 434.5 2.5 +0.57 72 1642 1800 600/2200 12339.6 CH, CO, SSTGosnell 53488.4 NNE 493.4 1.95 +0.49 98 1285.8 1800 800/2000 413.3 CH, CO, PK, SSTDifference 4631.0 58.9 0.55 26.0 356.2 0.0 400 11926.3


(1999) for resident cutthroat trout, and reported by Haas (in prep.) for bull trout in Skeena tributaries. Tributaries with large lakes in the headwaters will have seasonally moderated water temperatures and favor growing conditions in general. The pattern of bull trout use of non-lake headed tributaries was observed in the Morice watershed, where lake headed tributaries were not used by bull trout for rearing or spawning, whereas there is extensive use by anadromous species. This pattern requires further investigation to be substantiated. Recommendations Inventory Requirements Completion of radio telemetry studies in the Morice River have detected bull trout in watersheds in which a standard 1:20,000 Reconnaissance Fish and Fish Habitat Inventory (1:20k FFHI) did not report any bull trout present. This result emphasizes the importance of adequate sampling intensity in watersheds where bull trout are known to exist, and is suspected to be an important natal tributary. Therefore, an enhanced 1:20k FFHI completed to Resource Inventory Committee (RIC) standards for the entire Shelagyote River watershed is recommended. Enhanced sampling efforts directed at identifying critical bull trout staging, spawning, migration and juvenile rearing are recommended and considered an integral tool to strategic and operational planning. This may be achieved through proper timing of sampling, using methods other than electroshocking for sampling; methods such as seining, snorkeling and angling. Stream walks may also be useful to identify bull trout redds in reaches suspected to support spawning. The Fisheries Habitat Assessment Tool v2.0 (FHAT20) developed by BC Ministry of Fisheries, Information Management Branch, (http://www.for.gov.bc.ca/ric/Pubs/Aquatic/Fhat20/index.htm) may also prove to be a useful tool in assisting with the strategizing of site selection. Rule based fish distribution predictions resulting from FHAT20 will identify reaches suspected of containing bull trout. Reaches that have high probabilities of bull trout occurrences may be prioritized for sampling. The use of FHAT20 in this situation, should be critically reviewed to ensure it is a viable option in which to assist in improving sampling efficiency. Radio telemetry studies may also be conducted as they have been successful in identifying natal tributaries, migration routes, migration timing, spawning sites, adult rearing and staging, adult over-wintering sites, as well as, providing valuable information on the populations age and size-class distribution, growth and mortality rates. One of the greatest values of radio telemetry studies is the ability to measure the relative importance of sub-basins within larger watershed units. Therefore, a radio telemetry study for the Shelagyote should also contain samples of bull trout captured in the mainstem Babine River to determine use of other tributaries within the lower Babine River.


Radio telemetry should only be conducted following completion or concurrently with a watershed wide 1:20k FFHI. Habitat Protection Measures Bull trout are blue listed (vulnerable to extinction) by the Conservation Data Center of BC (CDC), and are an Identified Wildlife Species by the Forest Practices Code. This requires MELP and land stewards to provide a higher level of habitat protection to habitat used by these species. Access Management Road access to confirmed over-wintering and post-spawn recovery pools utilized by Shelagyote bull trout should be avoided. A minimum road development distance of 1 km between known or suspected sensitive sites is recommended. This distance would require an overland walk of one hour, which is considered a sufficient deterrent to most harvest situations. Further research into other significant spawning, holding or staging locations for adult bull trout should be conducted to identify sensitive areas. Radio telemetry or further angling surveys may achieve this objective. Fish-Stream Identification Fish-stream identification using methods described in the Fish-Stream Identification Guidebook (FSID) provides one of the best available tools for fish and fish habitat protection. However, where bull trout distribution is unknown or there is inadequate sampling intensity, it is recommended that all water-courses and waterbodies as defined by the FSID be considered bull trout habitat and afforded the highest level of habitat protection under the Forest Practices Code (FPC) until adequate sampling has been completed. Enhanced 1:20k FFHI will achieve this objective. Temperature Sensitive Streams The identification of temperature sensitive streams and the subsequent designation has not been explored for waters containing bull trout in Region 6. However, the application of riparian reserves for tributaries upstream of known bull trout spawning and rearing locations may prove to be an effective habitat protection measure. Reference to Parkinson & Haas (1996) identifies the importance of maintaining existing water temperatures at protecting bull trout habitat from invasion of colonizing species. Wildlife Habitat Areas Wildlife Habitat Areas (WHA's) may also be implemented for known bull trout spawning or staging areas. However, bull trout habitat use information is needed prior to implementation. Stream walks, radio telemetry and reconnaissance inventory may achieve this objective.


References: Bahr, M., (in prep.). Radio telemetry studies on Morice River watershed bull trout (S. confluentus). UNBC. Dept. of Biology M.Sc. candidate. Beere, M.C., 2000. Memo to File: 34250-20-Fish-Special Stocks/Char/Bull Trout; Shelagyote (Babine R. watershed) River file. Haas (in prep.). Maximum temperature and habitat interactions and preferences of bull trout (Salvelinus confluentus) and rainbow trout (Oncorhyncus mykiss). Johnson, O.W., M.H. Ruckelshaus, W., S. Grant, F.W. Waknitz, A.M. Garrett, G.J. Bryant, K. Neely. and J.J. Hard, 1999. Status Review of Coastal Cutthroat Trout from Washington, Oregon, and California. NOAA Technical Memorandum NMFS-NWFSC-37. McPhail, J.D. and J. Baxter, 1994. A review of bull trout life history and habitat use in relation to compensation and improvement opportunities. Dept. of Zoology and Fisheries Centre, UBC, BC. Parkinson, E. A. and G. Haas, 1996. The role of macrohabitat variables and temperature in defining the range of bull trout. Fisheries Project Report No. 51. BC Min. of Environment Lands and Parks, Van. BC Soto, C.G. and C.G. Burhanuddin, 1995. Clove oil as a fish anaesthetic for measuring length and weight of rabbitfish (Siganus lineatus). Aquaculture 136: 140-152. Triton Environmental Consultants, 1997. Reconnaissance Fish and Fish Habitat Inventory of Nilkitkwa Working Area, Bulkley Forest District. Prepared for: Pacific Shelagyote River bull trout life history 35 Inland Resources, West Fraser Mills, Smithers, BC. Paul Giroux Fisheries Inventory Specialist Skeena Region Smithers, BC cc: Darren Fillier, FES, Kispiox FD, New Hazelton Dana Atagi, Fisheries Section Head, Smithers


Appendix a: Fish Capture Data

Site Zone Easting Northing BT # Floy # Length Sex Age Tissue Comments1 9 617662 6167499 1 1875 44 F 10 1 Maturing1 9 617662 6167499 2 1874 49 M 10 2 kelt1 9 617662 6167499 3 1873 63.5 M 12 3 kelt1 9 617662 6167499 4 1872 54 ? 9 4 kelt1 9 617662 6167499 5 1871 55 F 8 5 kelt1 9 617662 6167499 6 1870 41 F 8 6 kelt2 9 615349 6170802 1 1877 59 M 11 7 kelt2 9 615349 6170802 2 1879 60 M 11 8 kelt2 9 615349 6170802 3 1878 36 ? 7 9 Maturing2 9 615349 6170802 4 no floy 33 ? 6 10 Maturing2 9 615349 6170802 1 SST, 4 CO, 1RB3 9 614352 6171726 1 1880 52 M 9 11 kelt3 9 614352 6171726 2 1881 62 M 12 12 kelt3 9 614352 6171726 3 1883 53 M 8 13 kelt; recap d/s 58km on Babine Oct. 16, 20003 9 614352 6171726 4 1884 42 M 6 14 kelt3 9 614352 6171726 n/a no floy 51 M n/a 15 captured April 26, 20003 9 614352 6171726 3 SST, 1 RB4 9 614026 6172446 NFC5 9 611722 6175542 NFC6 9 609832 6180653 NFC 3 potential staging pools in vicintiy of trib confluence

Shelagyote River: Bull Trout Sampling Results, Sept. 26, 200.

aspects of the life history of shelagyote river adult …aspects of the life history of shelagyote...

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