The Biodiversity of Flying Coleoptera Associated With
Total Page：16
File Type：pdf, Size：1020Kb
THE BIODIVERSITY OF FLYING COLEOPTERA ASSOCIATED WITH INTEGRATED PEST MANAGEMENT OF THE DOUGLAS-FIR BEETLE (Dendroctonus pseudotsugae Hopkins) IN INTERIOR DOUGLAS-FIR (Pseudotsuga menziesii Franco). By Susanna Lynn Carson B. Sc., The University of Victoria, 1994 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE STUDIES (Department of Zoology) We accept this thesis as conforming To t(p^-feguired standard THE UNIVERSITY OF BRITISH COLUMBIA 2002 © Susanna Lynn Carson, 2002 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. 1 further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department The University of British Columbia Vancouver, Canada DE-6 (2/88) Abstract Increasing forest management resulting from bark beetle attack in British Columbia's forests has created a need to assess the impact of single species management on local insect biodiversity. In the Fort St James Forest District, in central British Columbia, Douglas-fir (Pseudotsuga menziesii Franco) (Fd) grows at the northern limit of its North American range. At the district level the species is rare (representing 1% of timber stands), and in the early 1990's growing populations of the Douglas-fir beetle (Dendroctonus pseudotsuage Hopkins) threatened the loss of all mature Douglas-fir habitat in the district. In response to beetle populations and increasing management needs, forest managers initiated a 5-year operational research study on the impact of pheromone trapping and harvesting on flying beetle diversity. Beetle diversity was measured from pheromone baited and unbaited Lindgren funnel traps located in mature/old growth, beetle attacked, leading Fd habitat from preharvest, through 4/5th season postharvest conditions. Pheromone traps were baited with known Douglas-fir aggregation pheromones; frontalin, MCOL, and seudenol, and all traps were collected weekly or bimonthly through the duration of the seasonal Douglas-fir beetle flight (April/May through August/September) from 1994-1997. A total of 484,000 individuals, representing 625 identified species and recognisable taxonomic units (morphospecies), from 67 families were trapped in preharvest and postharvest baited and control sites. Whittaker plots indicate logarithmic species distributions for both pheromone-baited and control trap catches, although the rank position of species varied between treatment conditions and trapping year. Between pheromone-baited and control traps, under preharvest conditions, trap catch analysis resulted in significant differences (cx = 0.05) for eight out of nine diversity indices including; Margalef's (d), Shannon-Weiner (H'10), Brillouin, Fisher's (rx), Pielou's (J), 1-Simpson's (1-D), Taxonomic diversity (6), and Taxonomic distinctness (8*) . Significant differences between baited and control data across all treatment years (preharvest, post 1, post 2, post 3, post 4/5) were observed for 6 out of 9 indices. Similarities observed in species richness (S) and Margalef's (d) measures are thought to be an artefact of low sampling effort. Changes observed in diversity and species abundance are thought to have resulted from the disproportionate trapping of an unknown number of non-target species by pheromone-baited traps relative to unbaited traps. Differences in diversity observed across harvest years occurred within the context of, and in addition to, a dynamic and changing species assemblage responding to harvesting and the resulting habitat change. The results suggest that the effect of single species management, in this circumstance, is not limited to the target organism and pheromone trapping along with harvesting as part of an IPM program can influence species composition at the community level. TABLE OF CONTENTS Abstract ii List of Tables v List of Figures vi Preface / Acknowledgements vii CHAPTER I - Introduction and Overview 1 Sampling Techniques 8 Trap design 8 Sampling Design 10 Trap placement 10 Replication 12 Site Conditions 14 Topography/Climate and weather 14 CHAPTER II - Impact of Aggregation Pheromones on Old Growth Associated Flying Beetle Diversity 17 Introduction 17 Methods 21 Results 29 Discussion 42 Semiochemical composition 56 Trapping efficacy 59 Long term considerations 61 Summary.... 63 CHAPTER III - Impact of Harvesting on Pheromone Biased Diversity Sampling... 65 Introduction 65 Methods 69 Species distribution analysis 74 Diversity analysis 75 Species abundance - baited vs. control 76 Species trends 77 Results 77 Diversity analysis / Overview 100 Species Number (S) 101 Marqalef s (d) 103 Pielou's (J') 104 Brillouin 104 Shannon-Wiener (H'ig) 105 Simpson's M-X) 106 Fisher's (a) 107 Taxonomic Diversity (5) 107 Taxonomic Distinctness (5*) 108 Species abundance-baited vs. control 108 Species trends 110 Discussion 112 Impact of harvesting 113 Surging species abundance 114 Decreasing species abundance 121 Increasing species abundance 123 Depressed species abundance. 124 Harvesting summary 125 Pheromone Effect 128 Natural variation 136 Trapping efficiency 137 Systematic bias 139 iii Semiochemical variation 140 Summary 140 CHAPTER IV - Pheromones and Integrated Pest Management 142 Introduction 142 Pheromones, Insect Ecology, and Community Development 146 Management Impact 148 Containment and mop-up 148 Monitoring 151 Pheromone bias as context 152 Sources of Variation and Experimental Limitations 155 Species variation 155 Habitat variation 157 Study limitations 158 Pheromone composition 159 Site selection and replication 160 Summary 162 BIBIOGRAPHY 166 Appendix I Taxonomic support 183 Appendix II Statistical protocols for Douglas-fir beetle abundance 185 Appendix III Species data by trend 187 Appendix IV Tabular results, Chapter 3 diversity indices 210 iv List of Tables* Table 1.1 Site replication (preharvest conditions) 14 Table 2.1 List of non-target species known to aggregate to Douglas-fir beetle pheromone components 20 Table 2.2 Site list, trapping year, and biogeoclimatic classification for preharvest pheromone baited and unbaited sites 23 Table 2.3 Summary results of mean abundance/site and total abundance of flying beetle species under preharvest conditions 30 Table 2.M Twenty most abundant flying beetle species (preharvest) 38 Table 2.5 Richness, evenness and dominance measures of flying beetle diversity (preharvest) 41 Table 2M Species of flying Coleoptera statistically more or less abundant betwee pheromone baited and control sites (preharvest) 42 Table 3.1 Site list, trapping year, and biogeoclimatic classification for preharvest and postharvest pheromone baited and unbaited sites 69 Table 3.2 Site replication of baited and control data across treatment years 74 Table 3.3 Site list for 5-replicate diversity analysis, including harvest stage, trapping year, and biogeoclimatic classification 76 Table 3.H Summary results of total abundance and species number of flying beetles (preharvest and postharvest) 79 Table 3.5 Summary results of mean abundance/site and total abundance of flying beetle species (preharvest and postharvest) 80 Table 3.6 Ten most abundant beetle species listed by rank from pheromone baited and control sites 99 Table 3.7 Flying Coleoptera species statistically more or less abundant between pheromone baited and control sites (preharvest and postharvest) 109 Table titles have been abbreviated/paraphrased for length. v List of Figures* Figure 1.1 Distribution of Douglas-fir in North America 1 Figure 1.2 Northern Distribution of mature Douglas-fir 2 Figure 1.3 Site Map 13 Figure 2.1 Site Map - preharvest conditions 22 Figure 2.2 Diagrammatic representation of sampling design 25 Figure 2.3 Venn diagram of species distribution (preharvest) 36 Figure 2M Whittaker plot of species abundance (preharvest) 37 Figure 2.5 Whittaker plot of 20 most abundant species (preharvest) 37 Figure 2.6 Results of flying beetle diversity measures (preharvest) 40 Figure 3.1 Mean abundance/site of flying beetles in pheromone baited and control sites (preharvest and postharvest) 96 Figure 3.2 Whittaker plot of species abundance (preharvest and postharvest) 98 Figure 3.3 Results of flying beetle diversity measures in pheromone baited and control sites (preharvest and postharvest) 102 Figure 3.1/ Observed trends in flying Coleoptera trapped in pheromone baited traps under preharvest and postharvest conditions 111 Figure 3.5 Observed trends in flying Coleoptera trapped in unbaited control traps under preharvest and postharvest conditions 111 Figure 3.G Successive phases in the invertebrate community exploiting dead wood 115 Figure 3.7 Phases of ecosystem development after clear-cutting of a second growth northern hardwood forest 126 *Figure titles have been abbreviated/paraphrased for length. vi Acknowledgements The project seemed simple enough: Collect some beetle samples, identify them, analyze the results, and write a thesis. Five years, a half a million insects, 12 taxonomic specialists, 10 field personnel, 15 lab personnel, 7 funding agencies and supporting corporations and 1 baby later, the project is complete. A debt of gratitude goes to everyone who worked on, and supported the task. The