Dead Wood Is Anything but Dead. It Is the Lifeblood of an Intricate Web of Life in Which Insects Figure Prominently.”
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“Cucujus clavipes Fabricius, 1781 (Coleoptera: Cucujidae) word cloud” (© 2012 C.Wood via Tagxedo) “Dead wood is anything but dead. It is the lifeblood of an intricate web of life in which insects figure prominently.” ~ Grove and Hanula, 2006 University of Alberta Saproxylic Beetles (Coleoptera) Associated With Aspen Deadwood in Broad-Leaved Boreal Mixedwood Stands by Charlene Meridith Wood A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Conservation Biology Department of Renewable Resources ©Charlene Meridith Wood Fall 2012 Edmonton, Alberta Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission. Abstract I assessed deadwood-associated (i.e., ‘saproxylic’) beetles (Coleoptera) along a decay gradient of trembling aspen in mature deciduous stands of the boreal mixedwood forest in NW Alberta. Various collection methods were employed to sample saproxylic beetle species. Assemblages differed between host substrate types and decay classes. Many species were also associated with moss presence and percent bark cover. Although small (7 to 15.9 cm) diameter logs were most abundant in the stands, most indicator species were associated with logs ≥25 cm in diameter. Samples of saproxylic beetles varied greatly depending on collection method; however window trap captures were compositionally similar regardless of their placement (on snags or freely-hanging). This suggests that window traps are less appropriate for assessing small-scale habitat associations. Deadwood associations revealed here indicate that a wide range of substrate types, decay classes, and sizes are important features of saproxylic beetle habitats that should be retained for biodiversity conservation. Acknowledgements This adventure would not be possible without the support and encouragement of my family (Dad, Mom, Bryan, Grace, Alan, Jayne, and Lachlan) and friends. Thanks especially to Zaid Jumean, for his love, patience, and various contributions to the production of this thesis. I would like to thank my supervisors John Spence and David Langor for giving me the opportunity to carry out this study and suggestions on this thesis. I would also like to thank my committee, Ellen Macdonald, Nadir Erbilgin, and Maya Evenden for comments on the final thesis. Best wishes go to the Spence Lab members that I have had the pleasure to know. Your support has been integral to the production of this thesis, and your friendship has made the ride enjoyable! Much appreciation also goes out to my fellow ‘EMENDers’, especially Jason Edwards and Charlene Hahn, for creating a ‘home away from home’ for my two summers at camp. The striking Northern skies, campfires, and cribbage tournaments will not soon be forgotten. Finally, those years at EMEND are filled with lasting memories of Suzanne Abele – my “fast friend.” Statistical guidance was provided by Jaime Pinzón, Guillaume Blanchet, Stéphane Bourassa, Evan Esch, and Anne Oxbrough. Additionally, thanks to Zaid, Stéphane and Anne for useful suggestions on my chapters. I would also like to thank the many people at the Northern Forestry Centre (Canadian Forest Service) that helped with aspects of field work, species identification, and construction of collection devices (Daryl Williams, Colin Myrholm, Greg Pohl). In particular, thanks to Jim Hammond for guidance in the early stages of my project and ‘showing me the ropes’ with saproxylic beetles. I would also like to thank Daishowa Marubeni International Limited (DMI) for allowing sampling on their forest management area and Jim Witiw and Florence Niemi (DMI) for helpful discussion. Amy Jimmo, Emily Turton, Melanie von Engelhardt, Philip Hoffman, Kimberly Stang, and Tory Cullen assisted with fieldwork and/or sample processing. Additional thanks to Dustin Hartley and Stéphane for help with rove beetle and ground beetle identifications as well as Danny Shpeley, Dr. Ball, and the UASM collection. I would like to acknowledge the many editors and contributors to the online taxonomic website ‘BugGuide’, through which I was able to ask advice of many experts in various groups. Particular thanks go to Wolfgang Rücker, Andreas Herrmann, Yves Bousquet, Colin Johnson, Donald Chandler, Paul Johnson, Andrew Cline, and Vasilli Belov. Brewing support and general merriment were provided by Stéphane and Colin Bergeron. Financial support was given by a Natural Sciences and Engineering Research Council of Canada (NSERC) Postgraduate Scholarship and Queen Elizabeth II Scholarship, Alberta Conservation Association (ACA) Grants in Biodiversity, Natural Resources Canada (NRCan), Alberta Sustainable Resource Development (SRD), the Forest Resource Improvement Association of Alberta (FRIAA) through DMI and Canadian Forest Products (CANFOR), the Manning Forestry Research Fund, the Sustainable Forest Management Network, and the DMI grant held by David Langor (NRCan) for downed woody debris management and measurement research. Table of Contents 1. INTRODUCTION ........................................................................................... 1 1.1. Boreal Forest Landscapes .......................................................... 2 1.1.1. The Boreal Mixedwood Forest ......................................... 2 1.1.2. Broad-leaved Stands ....................................................... 3 1.2. Deadwood as Critical Habitat ...................................................... 5 1.2.1. Definition of Deadwood ................................................... 5 1.2.2. Deadwood Habitats ......................................................... 5 1.3. Study organisms in focus ............................................................ 8 1.3.1. Definition of ‘Saproxylic’ .................................................. 8 1.3.2. Saproxylic Beetles ......................................................... 11 1.4. Thesis structure ........................................................................ 14 1.4.1. Overall Objectives ......................................................... 14 1.4.2. Thesis Chapters ............................................................ 16 1.5. Literature Cited ......................................................................... 19 2. A COMPARISON OF COLLECTION METHODS FOR MEASUREMENT OF SAPROXYLIC BEETLE SPECIES RICHNESS AND ASSEMBLAGE COMPOSITION ........................................................................................... 30 2.1. Introduction ............................................................................... 30 2.2. Methods .................................................................................... 33 2.2.1. Study Area .................................................................... 33 2.2.2. Substrate Variables ....................................................... 35 2.2.3. Collection Methods ........................................................ 35 2.3. Analyses ................................................................................... 42 2.3.1. Beetle Determination and Classification ........................ 42 2.3.2. Data Manipulation and Analyses ................................... 45 2.4. Results ..................................................................................... 49 2.4.1. Species Richness .......................................................... 50 2.4.2. Assemblage Structure ................................................... 52 2.4.3. Species Associations .................................................... 57 2.4.4. Collection Method Performance .................................... 59 2.5. Discussion ................................................................................ 62 2.5.1. Window Traps ............................................................... 63 2.5.2. Rearing Methods: Funnels, Drums, and Emergence Traps ...................................................................................... 65 2.5.3. Hand-collecting ............................................................. 69 2.5.4. Conclusions .................................................................. 71 2.6. Literature Cited ......................................................................... 74 3. INFLUENCE OF ASPEN DEADWOOD DIAMETER ON SAPROXYLIC BEETLE ASSEMBLAGES IN BROAD-LEAVED BOREAL STANDS ........... 82 3.1. Introduction ............................................................................... 82 3.2. Methods .................................................................................... 84 3.2.1. Study Area .................................................................... 84 3.2.2. Deadwood Selection and Measurement ........................ 85 3.2.3. Beetle Samples ............................................................. 86 3.3. Analyses ................................................................................... 88 3.3.1. Species Richness