FLUVIAL BULL TROUT REDD SURVEYS ON THE ELBOW, SHEEP AND HIGHWOOD RIVERS, ALBERTA - Trout Unlimited Canada

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1 FLUVIAL BULL TROUT REDD SURVEYS ON THE ELBOW, SHEEP AND HIGHWOOD RIVERS, ALBERTA - Trout Unlimited Canada Submitted to: Trout Unlimited Canada Calgary, AB Submitted by: Applied Aquatic Research Ltd. Calgary, Alberta January 2008 File: AAR06-111

2 FLUVIAL BULL TROUT REDD SURVEYS ON THE ELBOW, SHEEP AND HIGHWOOD RIVERS, ALBERTA - Trout Unlimited Canada Submitted to: Trout Unlimited Canada Calgary, AB Submitted by: R. Popowich and G. Eisler Applied Aquatic Research Ltd. Calgary, Alberta January 2008 File: AAR06-111

3 ACKNOWLEDGMENTS The authors would like to thank Mr. J. Stelfox, Fisheries Biologist, Fish and Wildlife Division, Sustainable Resource Development, for his advice, assistance and comments on previous drafts. We would also like to extend our appreciation to Mrs. M. Bradley, GIS/Cartographic Technologist, Sustainable Resource Development, for development of the map figures displayed in this document.

4 TABLE OF CONTENTS Page 1.0 INTRODUCTION Project Overview Study Area Study Objectives APPROACH RESULTS AND DISCUSSION Elbow River Sheep River Highwood River Canyon Creek REFERENCES Personal Communication Literature Cited...15 LIST OF APPENDICES APPENDIX A PLATES APPENDIX B MAPS OF PAST REDD SURVEYS LIST OF FIGURES FIGURE 1 LOCATIONS OF SURVEY ROUTES FOR BULL TROUT REDDS... 3 LIST OF TABLES AND MAPS TABLE 1 SUMMARY OF FLUVIAL BULL TROUT REDD COUNTS ON THE ELBOW RIVER... 6 TABLE 2 SUMMARY OF FLUVIAL BULL REDD COUNTS ON THE SHEEP RIVER... 8 TABLE 3 SUMMARY OF FLUVIAL BULL REDD COUNTS ON THE HIGHWOOD RIVER MAP 1 MAP 2 MAP 3 MAP 4 LIST OF MAPS MAP OF REDD LOCATIONS AND START AND END POINTS OF REDD SURVEY ON THE ELBOW RIVER, MAP OF REDD LOCATIONS AND START AND END POINTS OF REDD SURVEY ON THE SHEEP RIVER, MAP OF REDD LOCATIONS AND START AND END POINTS OF REDD SURVEY ON THE HIGHWOOD RIVER, MAP OF REDD LOCATIONS AND START AND END POINTS OF REDD SURVEY ON CANYON CREEK, LIST OF PLATES PLATE 1 VIEW OF SNORKELER PERFORMING A VISUAL SURVEY FOR REDDS (SHEEP RIVER) PLATE 2 VIEW OF A BANK-SIDE OBSERVER PERFORMING A VISUAL SURVEY FOR REDDS (HIGHWOOD RIVER) Applied Aquatic Research Ltd. i

5 1.0 INTRODUCTION 1.1 Project Overview In general, populations of bull trout (Salvelinus confluentus) have declined throughout their native range (Post and Johnston 2002, Wissmar and Craig 2004). Bull trout carry a variety of threatened designations throughout its diminishing native range in western North America. In Alberta, bull trout are classified as a species of special concern and are the focus of numerous recovery efforts, including the implementation of a province-wide harvest ban in Reasons for bull trout decline are both biological and anthropogenic and include past mismanagement, migration barriers, competition and hybridization with invasive species, over-fishing, misidentification by anglers, poaching, and habitat loss (Kitano et al. 1994, Rieman et al. 1997, Swanberg 1997, Dunham and Rieman 1999, Neraas and Spruell 2001). These disturbances, in combination with narrow habitat preferences, slow growth rates, late maturity, and, in some instances, alternate-year spawning (Nelson and Paetz 1992, Post and Johnston 2002), have lead to decreasing population numbers, local extinctions, and numerous threatened designations throughout the native range in western North America (Rieman et al. 1997, Nelson et al. 2002, Popowich 2005). Studies of how these activities affect bull trout are complicated by the species life history. Bull trout in Eastern Slope drainages display three different life history strategies. Stream residents spawn, rear, and reside in tributaries or river headwaters. Adfluvial populations rear as juveniles in tributaries or river headwaters, migrate downstream to lacustrine environments until maturity, and return to spawn in natal streams. Fluvial populations also undergo migrations to and from natal streams; however, rather than maturing in lakes, the majority of growth occurs in larger streams and rivers. In the Elbow, Sheep and Highwood river drainages, both resident and fluvial life-history strategies exist. Not only do unique life-history stages of these populations require specific habitat types, but habitat requirements change through time (e.g., spawning vs. over-wintering). For example, habitat selection by fluvial populations varies in both space and time, making bull trout vulnerable to disturbances within the watershed (e.g., riparian development, water withdrawal, etc.) regardless of the location or timing of the activity. Alterations to watersheds can affect entire populations negatively, because bull trout have specific habitat requirements for spawning. Water temperature, substrate size and composition and ground-water influences have been cited as being the most prominent criteria influencing distributions of bull trout spawning and subsequent redd locations (Baxter and McPhail 1999, Baxter and Hauer 2000). It is important to identify these key areas within watersheds, because the timing and location of spawning activities represent the most vulnerable phase for bull trout. Hence, the protection of these areas has become an important priority among Eastern Slope management agencies in Alberta, evidenced by the closure of known bull trout spawning habitat to anglers in several watersheds. In the past, efforts have been made to identify these areas and to count redds and spawning bull trout in the Elbow, Sheep and Highwood rivers. Results have not only led to changes to angling regulations, but have also helped to estimate the number of adult bull trout in some populations. Alberta Sustainable Resource Development (ASRD) conducted redd surveys on the Highwood and Sheep rivers in the 1990s and on the Elbow River in More recently, Popowich (2005) conducted redd surveys in all three watersheds from 2003 to Applied Aquatic Research Ltd. 1

6 Counting and identifying the locations of redds is an inexpensive, non-invasive method of identifying important areas for spawning, as well as for monitoring population trends. However, the validity of this method assumes that counts are accurate and reflect the population status. Counting errors can result from a number of sources, including spatial and temporal variation in survey routes, inexperienced redd counters, water clarity, recent scouring of the substrate by high flows, and variation in characteristics of redds and the habitat in which they are constructed. Each of these sources of error were encountered during redd surveys from 2003 to Therefore, some of the counts obtained in years when survey conditions were suboptimal (e.g., 2004 and 2005) may not be a good index of the number of adult fluvial bull trout in the population. Consequently, we proposed that redd surveys be conducted in 2006 to obtain better counts than were obtained in 2004 and 2005, as well as to establish routes that will be used for future redd surveys. It should be noted that alternate-year spawning, a phenomenon known to occur in some populations of bull trout, can also complicate estimates. Underestimation of population size is the result, because not all mature fish spawn in consecutive years. Alternate-year spawning is suspected to occur in the Elbow, Sheep and Highwood rivers (Popowich 2005). 1.2 Study Area Redd surveys were conducted on Canyon Creek and the Elbow, Sheep and Highwood rivers. All of these watercourses are located along the Eastern Slopes of the Rocky Mountains, Alberta (Figure 1). The rivers begin in sub-alpine areas and proceed east through foothills, eventually flowing through prairie and farmland before entering the Bow River. The rivers are comparable in terms of geomorphology, temperature regime, and fish assemblage including native bull trout (Salvelinus confluentus), westslope cutthroat trout (Oncorhynchus clarkii lewisi), mountain whitefish (Prosopium williamsoni), and members of the cyprinid, catostomid, and cottid families. Non-native species in both rivers include brook trout (S. fontinalis), brown trout (Salmo trutta), and rainbow trout (Oncorhynchus mykiss) (Henderson and Peter 1969, Nelson and Paetz 1992). In the past, the Elbow River has been surveyed along an approximate 6-km section between Elbow Falls (impassable to upstream fish movement) and Paddy s Flat Campground. The Sheep River was also surveyed over an approximate 6-km section between a set of waterfalls known Triple Falls and the confluence of Gorge Creek. Similar to the Elbow River, this set of falls represents a logical starting point for redd surveys, since the falls are a barrier to bull trout migrating upstream. The Highwood River survey has usually been confined to an 11-km section of Storm Creek (the headwaters of the Highwood River), although an additional 4.5-km section of Storm Creek and a 24.3-km section of the Highwood River below Storm Creek were surveyed in 1994 (Buchwald et al. 2006). Selected sections were thought to encompass the most suitable bull trout spawning habitat in each river (J. Stelfox, ASRD, pers. comm.). Additionally, a short (~2.5 km) section of the upper part of Canyon Creek was surveyed by J. Stelfox in Applied Aquatic Research Ltd. 2

7 Fluvial Bull Trout Redd Surveys on the Elbow, Sheep and Highwood Rivers, Alberta Figure 1 Locations of survey routes for bull trout redds AAR January 2008 Applied Aquatic Research Ltd. 3

8 1.3 Study Objectives This project focused on counting redds in the each watershed as well as addressing shortcomings experienced during pervious redd surveys. Specifically, our objectives were to: i) Identify resident bull trout spawning habitat in Canyon Creek and fluvial bull trout spawning habitat in the Elbow, Sheep and Highwood rivers. We will compare redd location data with that gathered during previous surveys, to assess if spawning areas and habitat selection is changing through time. From this, we will establish a database that will grow through the addition of spatial data from future redd surveys; ii) iii) iv) Establish and describe redd survey routes in Canyon Creek and the Elbow, Sheep and Highwood rivers. We will replicate past surveys as well as increase the spatial scope of the existing data set by extending the length of past survey routes. This will address one of the problems associated with redd surveys inconsistent spatial coverage by surveyors; Address alternate-year spawning and site fidelity by counting tagged fish (if observed) and comparing their locations to those collected during other research projects in the watersheds; Add to previously established redd survey data sets to assay population trends; and v) Collect evidence of poaching. This information was readily determined in the Elbow and Sheep watersheds during previous radio telemetry studies; similar information might be readily obtained in this study. Applied Aquatic Research Ltd. 4

9 2.0 APPROACH From September 26 to 30, 2006, two fish biologists conducted redd surveys on the Elbow, Sheep and Highwood rivers, and Canyon Creek (Figure 1). To secure the most accurate counts possible, a single survey was conducted in each watercourse after spawning was suspected to be complete. This time frame was developed based on the timing of past surveys and anecdotal information provided by anglers that observed spawning bull trout in each river. The survey sections were selected based on past survey routes, as well as information provided by J. Stelfox (Provincial Area Fisheries Biologist, ASRD) and B. Meagher (Trout Unlimited Canada (TUC). Redd surveys were conducted by one snorkeler (where appropriate) and one stream-side observer proceeding downstream simultaneously (Plates 1 and 2, respectively). When redds were encountered, a UTM (Universal Transverse Mercator) was recorded (NAD 83 map datum) using a hand-held GPS (Global Positioning System) unit. This method has proved to be highly effective, because snorkelers can easily enumerate redds on a small scale while the streamside observer can view redds across the entire width of the river. When possible, fish community composition (abundance, size distribution and diversity) data were collected. All observed fish, regardless of species, were identified, counted, estimated for fork length (FL) (cm) and grouped by size class (0-9, cm, etc.). The locations of all fish were also recorded using a hand-held GPS unit. These data were submitted to ASRD for entry into the Fisheries Management Information System (FMIS). Applied Aquatic Research Ltd. 5

10 3.0 RESULTS AND DISCUSSION 3.1 Elbow River Conditions were optimal for counting redds when the Elbow River was surveyed on September 28 and 30, The Elbow River was surveyed in two sections: 1) Elbow Falls (11U E, N) to the downstream (east) end of Paddy s Flat Campground (11U E, N) and; 2) east end of Paddy s Flat Campground to Gooseberry Campground (11U E, N). The first section replicated the route surveyed in the past, while Section 2 was implemented to determine if spawning was occurring further downstream, which might necessitate changing the survey route in the future (Figure 1). A total of 32 redds were counted, all of which were located within Section 1 (Table 1 and Map 1). Relative to counts made during previous redd surveys within the same study section, it appears that the fluvial bull trout population has declined by about 30% since Survey conditions were ideal in 2002, 2003 and 2006, so these counts are considered an accurate reflection of the number of spawners in those years. However, high flows in late August 2004 scoured the substrate, making redds difficult to identify and may have resulted in some redds being missed in Therefore, the 2004 redd count should not be interpreted as indicating a sharp decline in redds in 2004 relative to TABLE 1 Summary of Fluvial Bull Trout Redd Counts on the Elbow River, Section Approximate Number of redds length of section (km) Elbow Falls Paddy's Flat Campground a 32 Paddy's Flat Campground Gooseberry Campground 9.0 ns ns ns 0 a High flows in 2004 resulted in poor survey conditions. Redds were difficult to distinguish, which may have resulted in lower counts. ns not surveyed. Based on these findings, in addition to redd data collected in 2002, 2003 and 2004 (Appendix B), we suggest that the survey route for fluvial bull trout redds on the Elbow River begin at Elbow Falls (11U E, N) and end at the downstream (east) end of Paddy s Flat Campground (11U E, N). This area has consistently and exclusively encompassed spawning areas used by bull trout over the past three surveys and could be considered as the standardized section during future surveys. Because only three bull trout greater than 30 cm long were observed during the spawning survey, and none of these fish were observed near redds, the timing of the survey appears to have followed the completion of spawning by most bull trout in the Elbow River. None of the bull trout observed had Floy or radio tags. Therefore, no assessment of alternate-year spawning could be made. Also, no direct evidence of poaching was encountered, other than a bait wrapper located at Elbow Falls. Applied Aquatic Research Ltd. 6

11 Map 1 Map of Redd Locations and Start and End Points of Redd Survey on the Elbow River Applied Aquatic Research Ltd. 7

12 3.2 Sheep River The 2006 Sheep River fluvial bull trout redd survey was conducted on September 27 and 29. To facilitate comparison of the data with data gathered during previous surveys, the river was divided into three sections: 1) Triple Falls (11U E, N) to the Gorge Creek confluence (11U E N); 2) the Gorge Creek confluence to the Dyson Creek confluence (11U E, N); and 3) the Dyson Creek confluence to an area known as Windy Point (11U E, N). The 2006 survey, like the 2003 survey, encompassed all three sections. In comparison, the 1996 redd survey only extended from Triple Falls to Gorge Creek (J. Stelfox, Sustainable Resource Development, pers. comm.). Similarly, surveys in 2004 and 2005 only extended from Triple Falls to a point (11U E, N) approximately 0.8 km downstream from Gorge Creek. Conditions were optimal for counting redds during the 2006 redd survey. In total, 243 bull trout redds were counted (Table 2 and Map 2). Most (88%) of these redds were found upstream from Gorge Creek, with the remaining redds (12%) being found within 1.5 km downstream from Gorge Creek. Although no redds were found in the section from Dyson Creek to Windy Point, the total number and spatial distribution of redds observed in 2006 was comparable to data collected in 2003 (Table 2; Appendix B). Comparison of the 2006 data with the 2004 and 2005 redd counts might suggest that the bull trout population was substantially lower in those years. However, it is likely that many redds were missed in 2004 and 2005, since high flows immediately prior to, during or shortly after the bull trout spawning period scoured the substrate, making it difficult to identify redds. Since the 1996 and 2003 redd surveys were not affected by scouring flows, it is more appropriate to compare the 2006 redd count with redd counts for those years. This comparison suggests that the adult fluvial bull trout population in the Sheep River increased about four fold over a sevenyear period after 1996 and has been relatively stable since Factors likely contributing to this increase are 1) the implementation of a province-wide zero bag limit for bull trout in 1995 and 2) the closure of the Sheep River upstream of Gorge Creek to angling in TABLE 2 Summary Table for Redd Counts on the Sheep River from Section Approximate Number of redds length of b 2005 b 2006 section (km) Triple Falls Gorge Creek Gorge Creek Dyson Creek 3.0 ns 6 25 a 0 a 29 Dyson Creek Windy Point 4.0 ns 1 ns ns 0 a Only the upper 0.8 km of this section was surveyed in 2004 and b High flows in 2004 and 2005 resulted in poor survey conditions. Redds were difficult to distinguish which may have resulted in lower counts. ns not surveyed. Based on the distribution of redds in 2003 and 2006, we suggest that all future fluvial bull trout redd surveys should encompass the section of river between Triple Falls and Dyson Creek. A total of 15 bull trout bull trout greater than 30 cm long were observed during the spawning survey. Of these, four were found in close proximity to redds. Given the large number of Applied Aquatic Research Ltd. 8

13 abandoned redds in comparison to the small number of spawning-sized fish observed in the surveyed area the survey s timing was suitable. While no radio-tagged fish were observed, a single Floy-tagged bull trout was encountered. Unfortunately, no assessment of alternate-year spawning could be made. Some evidence of poaching was encountered, including fishing line and lures located upstream of Gorge Creek, in the section closed to angling. A large bull trout was also found dead at the bottom of a pool; however, the cause of death could not be determined. Applied Aquatic Research Ltd. 9

14 Map 2 Map of Redd Locations and Start and End Points of Redd Survey on the Sheep River Applied Aquatic Research Ltd. 10

15 3.3 Highwood River The Highwood River was surveyed on September 26, However, given the reach s 15-km length and braided nature, it is recommended that this section be surveyed over two days in the future. The section surveyed extended from the Hwy 40 crossing of Storm Creek (11U E, N) (Highwood River headwaters) to the confluence between the Highwood River and Lantern Creek (11U E, N). For the purpose of this report, the watercourse will be referred to as the Highwood River. Conditions were optimal for counting redds. This survey encompassed the route surveyed most frequently in the past. In total, 67 redds were observed (Table 3 and Map 3). Compared to the 2003 redd count (Table 3 and Appendix B), the data might suggest that the population of adult fluvial bull trout in the Highwood River has increased in size substantially since However, compared to counts conducted in the 1990s (Buchwald et al 2006), the population is essentially the same. Conditions for counting redds were comparable between 2003 and 2006, although flooding in 2005 created many new braided sections in the surveyed area. TABLE 3 Summary of Fluvial Bull Trout Redd Counts on the Highwood River Section Length of Number of redds section (km) Hwy 40 crossing - Lantern Cr a 43 a, b 65 a Lantern Cr. - Loomis Cr. 3.0 ns ns b ns 4 ns a From Table 5 in Buchwald et al b An additional 30 redds were counted in the Highwood River in 1995 five above the Hwy 40 crossing and 25 between Mist Creek and the SR 940 bridge at Highwood House (Buchwald et al. 2006). ns not surveyed. Based on the distribution of redds, we suggest that the survey route for fluvial bull trout redds on the Highwood River begin at the Hwy. 40 crossing of Storm Creek and continue downstream to Lantern Creek. This area has consistently encompassed most of the bull trout redds found in previous surveys. Unlike the Elbow and Sheep rivers, the Highwood River is braided for much of this route. Consequently, channel instability makes it difficult to count redds and compare counts between years. Recent flooding has compounded the problem, as new channels have formed. We suggest that future surveyors anticipate these challenges and incorporate multiple GPS units, as well as two-way radios, to allow multiple channels to be investigated simultaneously. Four bull trout greater than 30 cm long were observed during the spawning survey. Given the large number of abandoned redds in comparison to the small number of spawning-sized fish observed in the surveyed area the survey s timing was suitable. None of bull trout observed had Floy or radio tags, therefore no assessment of alternate-year spawning could be made. Also, no direct evidence of poaching was encountered. Applied Aquatic Research Ltd. 11

16 Map 3 Map of Redd Locations and Start and End Points of Redd Survey on the Highwood River Applied Aquatic Research Ltd. 12

17 3.4 Canyon Creek Canyon Creek was surveyed on September 29, 2006, from where surface flow begins about 0.8 km upstream of Powderface Trail (11U E, N) to about 1 km below Powderface Trail. In total, six redds were counted (Map 4). This is twice as many redds as were counted in 2002 by J. Stelfox on September 21, when three redds were found in a 2.5-km section of Canyon Creek near Powderface Trail - two redds were observed ~0.5 km upstream of the road and one redd was observed ~0.9 km below the road. Conditions for counting redds were optimal in 2006 and A total of eight fish were observed during the redd survey. Unfortunately, only one of these was identified positively as a bull trout. As it was not observed near any of the redds, the timing of the survey is thought to have followed the completion of spawning. Similar to the Highwood River, much of the sampled area of Canyon Creek is braided. This is likely the result of flooding and the wide floodplain area adjacent to the Powderface Trail. We suggest that future surveyors anticipate these challenges and incorporate multiple GPS units, as well as two-way radios, to allow multiple channels to be surveyed simultaneously. We also recommend that future surveys encompass the 2006 survey route, but also extend further downstream, as this may result in the identification of additional spawning areas. No direct evidence of poaching was encountered. However, vehicle tracks and garbage were observed throughout the area. Applied Aquatic Research Ltd. 13

18 Map 4 Map of Redd Locations and Start and End Points of Redd Survey on Canyon Creek Applied Aquatic Research Ltd. 14

19 4.0 REFERENCES 4.1 Personal Communication Stelfox, J. Fisheries Biologist. Fish and Wildlife Division, Alberta Sustainable Resource Development, Cochrane, Alberta. 4.2 Literature Cited Baxter, C.V., and Hauer, R.F Geomorphology, hyporheic exchange, and selection of spawning habitat by bull trout (Salvelinus confluentus). Canadian Journal of Fisheries and Aquatic Sciences 57: Baxter, J.S., and McPhail, J.D The influence of redd site selection, groundwater upwelling, and over-winter incubation temperature on survival of bull trout (Salvelinus confluentus) from egg to alevin. Canadian Journal of Zoology 77: Buchwald, V.G., M.J.H. Rawles, and J. Wieliczko Bull trout spawning in the Highwood River, Fish and Wildlife Division, Alberta Sustainable Resource Development, Red Deer. 43 pp. Dunham, J.B, and B.E. Rieman Metapopulation structure of bull trout: influences of physical, biotic, and geometrical landscape characteristics. Ecological Applications 9: Henderson, N.E., and Peter, R.E Distribution of fishes in southern Alberta. Journal of the Fisheries Research Board of Canada 26: Kitano, S., Maekawa, K., Nakano, S., and Fausch, K.D Spawning behaviour of bull trout in the upper Flathead Drainage, Montana, with special reference to hybridization with brook trout. Transactions of the American Fisheries Society 123: Nelson, J.S. and M.J. Paetz The Fishes of Alberta (2nd ed.). The University of Calgary Press, Alberta, Canada. 437 pp. Nelson, M.L., McMahon, T.E., and Thurow, R.F Decline in the migratory form in bull charr, Salvelinus confluentus, and implications for conservation. Environmental Biology of Fishes 64: Neraas, L.P. and Spruell, P Fragmentation of riverine systems: the genetic effects of dams on bull trout (Salvelinus confluentus) in the Clark Fork River System. Molecular Ecology. 10: Popowich, R.C Determining bull trout (Salvelinus confluentus) habitat and prey selection using snorkel surveys and stable isotope analysis. M.Sc. Thesis, University of Alberta. Post, J.R. and Johnston, F.D Status of the bull trout (Salvelinus confluentus) in Alberta. Alberta Wildlife Status Report No. 39. Rieman, B.E., Lee D.C., and Thurow, R.F Distribution, status, and likely future trends of bull trout within the Columbia River and Klamath river basins. North American Journal of Fisheries Management 17: Applied Aquatic Research Ltd. 15

20 Swanberg, T.R Movements of and habitat use by fluvial bull trout in the Blackfoot River, Montana. Transactions of the American Fisheries Society 126: Wissmar, R.C. and Craig, S.D Factors affecting habitat selection by a small spawning charr population, bull trout, Salvelinus confluentus: implications for recovery of an endangered species. Fisheries Management and Ecology 11: Applied Aquatic Research Ltd. 16

21 APPENDIX A Plates Applied Aquatic Research Ltd. 17

22 Plate 1 View of snorkeler performing a visual survey for redds (Sheep River). Plate 2 View of a bank-side observer performing a visual survey for redds (Highwood River). Applied Aquatic Research Ltd. 18

23 APPENDIX B Maps of Past Redd Surveys Applied Aquatic Research Ltd. 19

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