Eastern Washington University EWU Digital Commons EWU Masters Thesis Collection Student Research and Creative Works 2015 Smallmouth bass abundance and diet composition in the upper Spokane River Michael Taylor McCroskey Eastern Washington University Follow this and additional works at: http://dc.edu/theses Part of the Biology Commons Recommended Citation McCroskey, Michael Taylor, "Smallmouth bass abundance and diet composition in the upper Spokane River" (2015). EWU Masters Thesis Collection.edu/theses/326 This Thesis is brought to you for free and open access by the Student Research and Creative Works at EWU Digital Commons. It has been accepted for inclusion in EWU Masters Thesis Collection by an authorized administrator of EWU Digital Commons. For more information, please contact jotto@ewu.
SMALLMOUTH BASS ABUNDANCE AND DIET COMPOSITION IN THE UPPER SPOKANE RIVER ________________________________________________________________________ A Thesis Presented To Eastern Washington University Cheney, Washington ________________________________________________________________________ In Partial Fulfillment of the Requirements For the Degree Master of Science _____________________________________________________________ By Michael Taylor McCroskey Fall 2015 THESIS OF TAYLOR McCROSKEY APPROVED BY ______________________________________ _____________ Dr. Paul Spruell, Graduate Study Professor Date ______________________________________ ____________ Dr. Camille McNeely, Graduate Study Committee Date ______________________________________ ____________ Dr. Stacy Warren, Graduate Study Committee Date ii MASTERS THESIS ,QSUHVHQWLQJWKLVWKHVLVLQSDUWLDOIXOILOOPHQWRIWKHUHTXLUHPHQWVIRUDPDVWHU¶VGHJUHHDW Eastern Washington University, I agree that the JFK Library shall make copies freely available for inspection.
I further agree that copying of this project in whole or in part is allowed only for scholarly purposes, of for financial gain, shall not be allowed without my written permission. Signature__________________________________________ Date_____________________________________ iii ABSTRACT I conducted a three month study, between June and August, in 2015 of Redband Trout (Oncorhynchus mykiss var. gairdneri) and Smallmouth Bass (Micropterus dolomieu) in the upper Spokane River in Washington, from the border between Washington and Idaho (rkm 154.5) to Harvard Road (rkm 149. The primary goals of the project were to: (1) determine the abundance and density of Redband Trout and Smallmouth Bass in the Starr Road area, as well as two reference sites, prior to possible habitat manipulation, (2) estimate the Smallmouth Bass population and density between the Washington/Idaho Stateline and Harvard Road, and (3) determine the rate of piscivory on Redband Trout by Smallmouth Bass.
Day and night snorkel surveys were conducted to determine abundance and density at the Starr Road experimental site, and two additional references sites. Only two adult and three juvenile Redband Trout were at any of the sites during the study, therefore no statistical testing was done. There were significantly more Smallmouth Bass were observed at Starr Road (n=2692) than either reference site 1 (n=864) and site 3 (n=901) (p = < 0. The Smallmouth Bass population between the Washington/Idaho Stateline and Harvard Road was estimated by mark/recapture techniques.
Fish, collected by raft HOHFWURILVKLQJDQGDQJOLQJPPZHUHWDJJHGZLWKD)OR\WDJDQGILVKPPZHUH tagged with elastomer. Fish were also given right pelvic fin clip if captured by angling and a left pelvic fin clip if captured by electroshocking. I used an open population model POPAN in the mark program to conduct estimates for both Smallmouth Bass PP7/DQG6PDOOPRXWK%DVV7/DQGPP7/3RSXODWLRQVHVWLPDWHV 6( 95% CI; AIC value) were 1,645 (SE=287; 95% C. =1,171-2,310, AIC=429) 6PDOOPRXWK%DVVPPDQG 6( &, -1807, AIC=402) 6PDOOPRXWK%DVVPP7/'HQVLW\RI6PDOOPRXWK%DVVPP7/DQGPP TL were 284 fish/km and 225 fish/km, respectively.
In a previous study conducted by the Washington Department of Fish and Wildlife in (2009), the Smallmouth Bass population PP7/ &, EHWZHHQWKH6WDWHOLQHRI:DVKLQJWRQDQG,GDKRWR0F0LOOLDQ iv Road was estimated at 902 (524-1691) and had a density of 100 fish/km. The density of 6PDOOPRXWK%DVVPP7/LQFUHDVHGSHUFHQWEHWZHHQ DQG A diet survey was conducted to determine the amount of predation occurring on Redband Trout by Smallmouth Bass. No predation of Redband Trout by Smallmouth Bass was observed during the study, though only 5 young-of-the-year Redband Trout were seen during the entirety of the study. Smallmouth Bass in the study area consumed substantial numbers of non-salmonid fish, which comprised 33 percent of their diet by weight.
v TABLE OF CONTENTS Table of &RQWHQWV««««««««««««««««««««««««««««YL /LVWRI7DEOHV«««««««««««««««««««««««««««««YLLL /LVWRI)LJXUHV«««««««««««««««««««««««««««««L[ INTRODUCTION %DFNJURXQG««««««««««««««««««««««««««« 3XUSRVHRI3URMHFW««««««««««««««««««««««««« 2EMHFWLYHV«««««««««««««««««««««««««««« STUDY AREA 6WXG\/RFDWLRQ«««««««««««««««««««««««««« +DELWDW6WUXFWXUHV«««««««««««««««««««««««« METHODS 6LWH6HOHFWLRQ«««««««««««««««««««««««««« 6QRUNHO6XUYH\«««««««««««««««««««««««««.12 Mark-Recapture 6XUYH\«««««««««««««««««««««« Predation SXUYH\««««««««««««««««««««««««« RESULTS 6QRUNHO6XUYH\««««««««««««««««««««««««« Mark-RecapWXUH««««««««««««««««««««««««« Predation SXUYH\««««««««««««««««««««««««« DISCUSSION Snorkel SurvH\««««««««««««««««««««««««« vi Mark-RecapWXUH««««««««««««««««««««««««« PredatiRQ«««««««««««««««««««««««««««« CONCLUSION«««««««««««««««««««««««««««« MANAGEMENT IMP/,&$7,216«««««««««««««««««««« /LWHUDWXUH&LWHG«««««««««««««««««««««««««««« vii LI ST OF TABLES Table 1. Smallmouth Bass total number, abundance, and density for snorkel surveys conducted at sites 1-««««««««««««««««««« Table 2. Estimated abundance (95% CI) and density for Smallmouth Bass PPLQ DQG6PDOOPRXWK%DVVPPDVZHOODV PPLQ «««««««««««««««««««««««« Table 3. Catch (n), effort, and catch-per-unit-effort (CPUE) for Smallmouth Bass by electrofishing DQGDQJOLQJLQ««««««««« Table 4.
Catch per unit effort (CPUE) of Smallmouth Bass in 2009 compared to «««««««««««««««««««««««« Table 5. Mean length (±SD), mean weight (±SD), and range of Smallmouth Bass captured in 2009 anG«««««««««««««««««««« Table 6. Age class structure of Smallmouth Bass captured in 2015, with mean total length TL (± SD) and mean weight Wt (± SD «««««««««« Table 7. Back-calculated lengths of Smallmouth Bass in the upper Spokane RiveU««««««««««««««««««««««« Table 8.
Diet of Smallmouth Bass by each month sampled, June through August 2015, in the upSHU6SRNDQH5LYHU«««««««««««««- 44 Table 9. Diet of Smallmouth Bass by 50mm TL size class in the upper Spokane River from Washington/Idaho to Harvard 5RDG«««««««««- 47 viii LI ST OF FI GURES Figure 1. Map of Washington, Idaho, Oregon with upper Spokane River QRWHG««««««««««««««««««««««««««««« )LJXUH$UHDRIVWXG\LQXSSHU6SRNDQH5LYHU««««««««««««««« Figure 3. Snorkel and minnow trapping survey locationV«««««««««««« Figure 4.
Total number of fish observed in sites 1-«««««««««««««« Figure 5. Mean count of Smallmouth Bass over entirety of study in sites 1-«««««««««««««««««««««««««« Figure 6. Mean count of Smallmouth Bass, comparing night vs. day, in sites 1-«««««««««««««««««««««««««« Figure 7.
Mean count of Smallmouth Bass 0-100mm TL size class, comparing night vs. day, sites 1-««««««««««««««««« Figure 8. Mean count of Smallmouth Bass 0-100mm vs. 100-450mm TL, comparing night vs.
day, in sites 1-«««««««««««««««« Figure 9. Mean count of piscivorous size class Smallmouth Bass, 155-370mm TL, in sites 1-«««««««««««««««««««« ix ACKNOWLEDGEM ENTS I would like to thank my advisor, Dr. Paul Spruell of Eastern Washington University, for the opportunity to become one of his graduate students and all the help with my project, as well as thesis. I would especially like to thank him in helping me to better my abilities, knowledge, and skill in my education career in the Masters of Science program.
For allowing me to conduct the project for the Washington Department of Fish and Wildlife (WDFW), as well as helping to plan, conduct, and give support as needed, I would like to thank Charles D. Lee of the WDFW. I would like to thank Dr. Peggy 2¶&RQQHOOWKH%LRORJ\'HSDUWPHQWFKDLUIRUDOOKHUKHOSDQGJXLGDQFHLQKHOSLQJPHWR get through my graduate career.
I would like to thank Dr. Camille McNeely, one of my committee members, for all the extra support and finesse in the way my graduate studies were handled. I would like to thank my other graduate committee member, Dr. Stacy Warren, for all the help in geographic information systems and the help with making maps for my thesis.
I would also like to acknowledge Dr. Allan Scholz, for all his help and guidance in a variety of data analysis, edits to my thesis, and all the questions he DQVZHUHGGXULQJP\JUDGXDWHFDUHHU$QRWKHUSHUVRQ¶VKHOSWKDWZDVDEVROXWHO\HVsential during the statistical analysis portion of my working with, and analyzing, my data was Dr. I would also like to thank Bill Abrahamse, the president of the Spokane Falls Chapter of Trout Unlimited, for his help and involvement in working with the university to ensure proper funding and handling of the project. ,ZRXOGOLNHWRDFNQRZOHGJHDOOWKRVHLQWKH(DVWHUQ:DVKLQJWRQ8QLYHUVLW\¶V Fisheries Research Center that spent time working on my project: Derek Entz, Sam Gunselman, Tyler Janasz, Jessica Walston, Shawna Warehime, Bryan Witte.
I would like to thank the Spokane Falls Chapter of Trout Unlimited, Silverbow Fly Shop, and Clearwater Fly Casters for providing the research funding for my project. Without their gracious financial help, I would not been able to conduct the research for P\SURMHFW,ZRXOGDOVROLNHWRWKDQN-DVRQ2¶&RQQRURIWKH.DOLVSHOO7ULEHRI,QGLDQV fisheries department, for allowing me to use the raft electrofisher. I would also like to thank those that came out to help angle on August, 26, 2015, which included: Spokane x RiverKeeper, members of the Spokane Falls Chapter of Trout Unlimited, Rich Landers of the Spokesman Review, Fay Mills, Michael McCroskey, and Ryan Bailey. xi I ntroduction Throughout the western United States, the decline and extinction of native fish populations have been attributed to the introduction of non-native species (Wydoski and Bennett 1981; Moyle et al.
1986; Miller et al. While some invasions of exotic species have had no discernable impact on native species, others have had disastrous effects that have caused extinctions and altered entire ecosystems (Spencer et al. 1991; Lodge 1993; Vitousek et al. 1996; Strayer et al.
1999; Vander Zanden et al. How introduced fishes interact with, reduce, or eliminate native species is often unknown, but some factors may include: competition, predation, habitat alteration, genetic effects, and disease transmission (Moyle et al. The intentional or unintentional, introduction of most fish has had negative effects on the native fishes and the ecosystem through predation (Allendorf 1991). Introduced species can alter the habitat selection and prey availability of native species through competition for prey items, as well as prey on native species themselves (Crowder 1980, He and Kitchell 1990, Weidel et al.
The effects of predation are wide spread, not only within the predator/prey relationship but also throughout the food web. Prey use a number of behavioral traits to escape predation (Endler 1986; Carter et al. 2010), whereas predators must determine where, when, and how to capture prey (Dill 1983, Carter et al 2010). It is unpredictable what consequences introductions of non-native species will have when they persist alongside native species (Zimmerman 1999).
In the Pacific Northwest (PNW), the most common introduced fishes are native to the shallow, warm waters of the eastern United States (Bonar et al. Throughout the late 19th and early 20th centuries in western United States, the U. Fish Commission and European settlers stocked lakes, ponds, and rivers with a variety of non-native species (Lampman 1946; Wydoski and Whitney 1979; Bonar et al. 2005), including: centrarchids, ictalurids, percids, and salmonids.
Today, littoral predators continue to expand their ranges by unauthorized introductions and dispersal throughout drainage networks (Vander Zanden et al. One introduced fish species that has had a major effect on the native salmonids in the PNW through predation is the Smallmouth Bass (Micropterus dolomieu). The native range of the Smallmouth Bass encompasses from the Great Lakes, St. Lawrence River, and Mississippi River drainage (Carey et al.
The range of Smallmouth Bass has now expanded their range across North America, as well as the European, Asian, and African continents as a result of intentional stocking to provide angling opportunities (Scott and Crossman 1998; Sharma et al. Smallmouth Bass occupy both lentic and lotic environments in the PNW, inhabiting hundreds of lakes in Washington, Idaho, and Oregon, (Pflug and Pauley 1984; Fayram and Sibley 2000; Carey et al. 2011) as well as the Columbia River and Snake Rivers (Tabor et al. 1993; Zimmerman and Parker 1995; Naughton et al.
2004; Carey et al. In western North America, Smallmouth Bass have impacted salmonid populations, both anadromous and resident, through predation on fry and smolts (Harvey and Karevia 2005; Sharma et al. In most ecosystems Smallmouth Bass are considered a top predator (Olson and Young 2003; Warren 2009; Carey et al. A shift in diet from invertebrates and zooplankton to crayfish and fish occurs as the Smallmouth Bass grow from juvenile to the adult stage.
This shift to piscivory may have the greatest impact on native fishes. Piscivorous fishes influence the distribution, habitat selection, feeding space and time, as well as the immigration/emigration of other fish species (Power et al. 1985; Jackson et al. 2001; MacRae and Jackson 2001).
Smallmouth Bass piscivory on juvenile salmonid populations could potentially have major impacts if Smallmouth Bass abundance increased over time or if their distribution shifted resulting in more juvenile salmonids to in their diet (Fayram and Thomas 2000).