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Retention, Movement, and the Biotic Response to Large Woody Debris in the Channelized Missouri River

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Retention, Movement, and the Biotic Response to Large Woody Debris in the Channelized Missouri River View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by DigitalCommons@University of Nebraska University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Dissertations & Theses in Natural Resources Natural Resources, School of 2010 Retention, Movement, and the Biotic Response To Large Woody Debris in the Channelized Missouri River Michael W. Archer University of Nebraska at Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/natresdiss Part of the Aquaculture and Fisheries Commons, Natural Resources and Conservation Commons, and the Terrestrial and Aquatic Ecology Commons Archer, Michael W., "Retention, Movement, and the Biotic Response To Large Woody Debris in the Channelized Missouri River" (2010). Dissertations & Theses in Natural Resources. 6. https://digitalcommons.unl.edu/natresdiss/6 This Article is brought to you for free and open access by the Natural Resources, School of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Dissertations & Theses in Natural Resources by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Retention, Movement, and the Biotic Response To Large Woody Debris in the Channelized Missouri River By Michael W. Archer A Thesis Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science Major: Natural Resource Sciences Under the Supervision of Professor Mark A. Pegg Lincoln, Nebraska December 2009 Retention, Movement, and the Biotic Response To Large Woody Debris in the Channelized Missouri River Michael Archer M.S. University of Nebraska 2009 Advisor: Mark Pegg Large woody debris (LWD) is an important component of a healthy aquatic ecosystem. However, little is known about the dynamics of LWD in a large, channelized river such as the Missouri River. My objectives were to first, assess the abundance of LWD found along the channelized portion of the Missouri River. Second, I documented movement of LWD that entered the river. Lastly, using PRIMER software I analyzed what effect, if any, river segments, bend types, and LWD had on the community composition of the macroinvertebrate and fish that inhabit the river. Abundance of LWD was greater along bends that have flow diverted away from the bank compared to bends that had recent modifications to divert flow to the shore (major modification bends) and areas with little bank armoring, such as, side channel chutes (P<0.05). Recruitment of LWD into the river that could become available as aquatic habitat occurred mostly within 5 m of the bankfull width (BFW). Telemetry analysis of LWD showed that LWD located within the BFW of the river was often (63% of LWD) displaced downstream. Minimum distance of displaced LWD was 0.02 rkm, median distance was 146.50 rkm, and maximum distance was 1454.69 rkm. No differences were found in the community composition of macroinvertebrates between segments (P=0.43) or between bend types (0.074). Community composition did differ between LWD and non-LWD sites (P=0.016). Fish communities differed between the segments (P=0.043) therefore further analyses were split between the segments. Segment 8 fish communities did not differ between bend types (P=0.35) or between LWD and non-LWD sites (P=0.55). Results were similar in Segment 9 (bend types (P=0.20), LWD and non-LWD sites (P=0.19)). Combining the macroinvertebrate communities and fish communities to test for differences in the combined biota community composition showed that differences did not exist between the segments (P=0.59) or bend types (p=0.29). However, the composition of the composite community was different between LWD and non-LWD sites (P=0.011). My results suggest that while retention of LWD is low it still has an effect on the composition of the composite communities that inhabit the Missouri River. v iv Acknowledgments I would like to begin by thanking my family. Thank you to my mother for your constant encouragement, positive attitude, and showing me that learning is a lifelong adventure. Thank you to my father for teaching me about the natural world through the eyes of a sportsman. I have always cherished the time we spent together camping, fishing, and hunting. Thank you to my grandmother for your generous support that allowed me to return to school and chase my dreams. I would also like to thank my wife and best friend. There is no measure large enough to describe the love, support, patience, and understanding you have given me, thank you. I would also like to thank the Nebraska Game and Parks Commission for funding, support, and guidance. In particular I would like to thank Gerald Mestl for making this all possible. I would also like to thank Schuyler Sampson for his support and statistical expertise, Tim Porter and Brandon Eder for being so cooperative in sharing their equipment, and the rest of the Missouri River crew for their daily words of encouragement and resisting the temptation of dragging LWD up river. I would also like to thank all of the technicians who proved to be invaluable to the completion of this project. Landon Pierce, Joe Holdren, Drew Paprocki, Drew Podany, Phil Stollberg, Derek Tomes, and Evy Santiago spent many hours in the hot sun counting and measuring trees, standing waist deep in Missouri River mud, and wrangling carp into the live well. I would also like to thank Jordan Katt who helped me prepare for the field season by organizing the coop and locating equipment. I also want to extend a very v special thank you to Aaron Blank. His hard work, dedication, and friendship were crucial to the completion of this project and my sanity. The experience of graduate school has been one of the most enjoyable times of my life. This is in large part because of the wonderful people that I got to experience this with. Brenda Pracheil’s fine taste in music and constant encouragement, Ben Neely’s quick wit and willingness to help, and Jen Hogue’s free spirit and awesome Boston accent, all made going in everyday a welcome experience. Thank you to Marty Hamel for his willingness to help, encouragement, and most importantly his friendship. I would especially like to thank Tony Barada for everything he has done to help me see this project to the finish. He is the very definition of a friend and was always there to lend a hand and share a laugh. To the glorious and illustrious graduate committee of Dr. Richard Holland, Dr. Kevin Pope, and Mr. Gerald Mestl thank you for all of your guidance and wisdom. There are not thanks enough to extend to Dr. Mark Pegg. You have provided guidance when needed, patience when mistakes were made, and unexpected praise. Thank you for taking a chance on the old fat guy. I will be forever indebted to you for not only providing me with this experience but making it one of the greatest. v vi Table of Contents Abstract……………………………………………………………………………………………….ii Acknowledgments……………………………………………………………………………………..iv List of Tables……………………………………………………………………………………………vii List of Figures…………………………………………………………………………………….viii Chapter 1 LARGE WOODY DEBRIS AND ITS EFFECTS IN A LOTIC SYSTEM ……………………………………………………………………………………….1 References………………………………………………………………..6 Chapter 2 LARGE WOODY DEBRIS IN THE MISSOURI RIVER: ABUNDANCE, RECRUITMENT, AND RETENTION ………………………………………………………………………………….…………………………………………………………………………………………………….8 Introduction…………………………………………………………………………………………………….8 Methods…………………………………………………………………………………………………….………………………………………………………………13 Study Areas…………………………………………………………………………………………………….………………………………………………………………13 Data Collection………………………………………………………………14 Results…………………………………………………………………………………………………………………….………………………………………………17 LWD Abundance………………………………………………………………17 Movement………………………………………………………………18 Discussion………………………………………………………………19 References………………………………………………………………23 Chapter 3 BIOTIC COMMUNITY RESPONSE TO LARGE WOODY DEBRIS IN A LARGE CHANNELIZED RIVER ………………………………………………………………………………………………………………………………………………………….………………37 Introduction………………………………………………………………37 Methods……………………………………………………………………………………………………………………………………….……………………………38 Study Areas………………………………………………………………38 Biota Abundance………………………………………………………………39 Data Analysis………………………………………………………………40 Results………………………………………………………………………………………………………………………………………….…………………………41 Discussion………………………………………………………………44 References………………………………………………………………48 Chapter 4 MANAGEMENT CONSIDERATIONS AND FUTURE RESEARCH …………………………………………………………………………………………………………………………………………………………………….……62 Introduction………………………………………………………………62 The Missouri River………………………………………………………………62 Applied Knowledge, Future Research, and Management 63 Considerations ……..…………………..……………..…… Conclusions………………………………………………………………64 References………………………………………………………………66 vi Appendix A. ……………………………………………………………………………….68 vii List of Tables Table 2-1. Modified version of Hennon’s et. al. (2002) decay classification ratings used to classify large woody debris. …………………………………………………..26 Table 2-2. Data collected on LWD found at 8 study bends along the Missouri River in summer of 2007. Asterisk denotes bends that were sampled fully……………...27 Table 3-1. Lehtinen et al. (1997) snag rating index. Each variable is given a rating value from 0 to 4. Values are then added for a snag rating index number. Snag scores can range from 0 to 12. ………………………………………………………….51 Table 3-2. Results of SIMPER analysis showing the relative contribution to community similarity for biota sampled in
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