Evaluation of Sampling Gear for Predicting Harvest Size, Yield and Incidence of Stunting in Crawfish Ponds.

Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1997 Evaluation of Sampling Gear for Predicting Harvest Size, Yield and Incidence of Stunting in Crawfish Ponds Jimmy Lee Avery Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Avery, Jimmy Lee, "Evaluation of Sampling Gear for Predicting Harvest Size, Yield and Incidence of Stunting in Crawfish Ponds." (1997) LSU Historical Dissertations and Theses 6536 https://digitalcommons.lsu.edu/gradschool_disstheses/6536 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons For more information, please contact gradetd@lsu.edu INFORMATION TO USERS This manuscript has been reproduced from the microfilm master UMI fifans the text directty from the original or copy submitted Thus, some thesis and dissertation copies are in typewriter c^ while others may be from aity type o f computer printer The quality o f this reproduction is dependent upon the quality o f the copy subm itted Broken or indistinct print, colored or poor quality illustrations and photogr^hs, print bleedthrough, substandard margins, and improper alignment can adversely afreet reproduction In the unlikdy evoit that the author did not send UMI a complete manuscript and there are missing pages, these will be noted Also, if unauthorized copyright material had to be removed, a note will indicate the deletion Oversize materials (e g., maps, drawings, charts) are reproduced by sectionmg the original, b^inning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps Each original is also photogrqrhed in one exposure and is included in reduced form at the back o f the book Photographs included in the orignal manuscript have been reproduced xerographically in this copy Higher quality 6” x 9” black and white photographic prints are available ft)r any photographs or illustrations appearing in this copy fi>r an additional charge Contact UMI directly to order UMI A BeU & HoweD InfbiinatkHi Omqiany 300 North Zeeb Road, Ann Arbor MI 48106-1346 USA 313/761-4700 800/321-0600 R ep ro d u ced with p erm ission o f th e copyright ow ner Further reproduction prohibited w ithout perm ission Reproduced with permission of the copyright owner Further reproduction prohibited without permission EVALUATION OF SAMPLING GEAR FOR PREDICTING HARVEST SIZE, YIELD AND INCIDENCE OF STUNTING IN CRAWFISH PONDS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor o f Philosophy m The School o f Forestry, Wildlife, and Fisheries by Jimmy L Avery B.A., University o f Mississippi, 1980 M S., Delta State University, 1982 December 1997 R ep ro d u ced with p erm ission o f th e copyright ow ner Further reproduction prohibited w ithout perm ission UMI Number: 9810824 UMI Micrororm 9810824 Copyright 1997, by UMI Company All rights reserved This microform edition Is protected against unauthorized copying under Title 17, United States Code UMI 300 North Zeeb Road Ann Arbor, MI 48103 R ep ro d u ced with p erm ission o f the copyright ow ner Further reproduction prohibited w ithout p erm ission ACKNOWLEDGMENTS I wish to express my sincere gratitude to Dr Robert P Romaire, Professor o f Fisheries, for serving as my major professor during the preparation o f this dissertation and advancing my knowledge o f crawfish research and production I would also like to thank Dr Robert C Reigh, Professor o f Fisheries, fi>r his guidance and patience during my graduate studies and early research efforts I am especially grateful to Dr W Ray McClain, Adjunct Associate Professor o f Fisheries, for his collaboration and providing the data for analysis I also wish to express my appreciation to the other members of my graduate committee; Drs James W Avault, Jr., Professor Emeritus o f Fisheries, Terrence R Tiersch, Associate Professor of Fisheries, and William B Stickle, Jr., Professor o f Zoology and Physiology, for reviewing this manuscript and supporting its completion I would gratefully like to acknowledge the support o f my administration; especially Drs Jack L Bagent, Director of the Louisiana Cooperative Extension Service, Albert J Ortego, Division Leader, and Kenneth J Roberts, Project Leader, without which I could not have reached this goal I also would like to thank research associates; Mrs Sandra Malone, Vernon Pfister, and Jay Stander, and graduate student, Ken Couch, for their assistance during this and earlier research efforts This dissertation is the culmination of seven years of graduate studies and various research efforts I could not have continued through the various set-backs without the patience and support o f my family Part o f this accomplishment belongs to my loving parents Sue and Bob Avery, who have always encouraged and inspired me to succeed To my loving wife Bethe, I will never be able to fully express my R ep ro d u ced with p erm ission o f the copyright ow ner Further reproduction prohibited w ithout perm ission appreciation for your sacrifices and willingness to assume most o f the responsibilities of maintaining our family To my daughters, Lauren and Elizabeth, thank you for allowing me to trade some o f our time together for this accomplishment in R ep ro d u ced with p erm ission o f the copyright ow ner Further reproduction prohibited w ithout p erm ission TABLE O F CONTENTS Acknowledgments ii List o f Tables vi List o f Figures .ix Abstract xi Introduction I Literature Review Materials and Methods 12 Study Site and Pond Management 12 Sampling Protocol 14 Harvesting Protocol 20 Relative Density, Standing Crop, and Biomass Estimates .20 Regression Models 23 Predictive Models 28 Results 31 Range o f Observed Values 31 Relative Density, Standing Crop,and Biomass Estimates 31 Regression Models 48 Predictive Models 66 Discussion 85 Relative Density, Standing Crop,and Biomass Estimates 85 Predictive Models 89 Limitations of Sampling Gear 98 Limitations of Model 102 Conclusions and Recommendations 104 Conclusions 104 Recommendations 107 Literature Cited 110 Appendix A: Cross validation iterations for the dip-net prediction m odel 116 Appendix B: Cross validation iterations for the test trap prediction model .119 Appendix C: Estimated costs and returns per hectare, rice-crawfish double crop, owner operators, southwest Louisiana, 1997 122 IV R ep ro d u ced with p erm ission o f the copyright ow ner Further reproduction prohibited w ithout perm ission Appendix D; Linear regression coefficients o f the dip-net sweep, test trap catch, and drop sampler catch prediction models 124 V ita .127 R ep ro d u ced with p erm ission o f the copyright ow ner Further reproduction prohibited w ithout p erm ission LIST OF TABLES Annual experimental conditions for crawfish production studies (1991 to 1996) Rice Research Station, Louisiana Agricultural Experiment Station, LSU Agricultural Center, Crowley, Louisiana 15 Yield and size distribution at harvest information for crawfish production studies (1991 to 1996) Rice Research Station, Louisiana Agricultural Experiment Station, LSU Agricultural Center, Crowley, Louisiana 32 Monthly means (± SD) and minimum and maximum values (in parentheses) o f monthly observations for dip-net sweep catch, test trap catch, and drop sampler catch for Rice Research Station crawfish studies (1991 to 1996) 37 Mean (± SD) relative density estimates (crawfish/dip-net sweep) fiom dipnet sweep sampling gear for Rice Research Station crawfish studies (1991 to 1996) grouped by original treatment or year .39 Mean (± SD) relative density estimates (crawfish/trapset) firom test trap sampling gear for Rice Research Station crawfish studies (1991 to 1996) grouped by original treatment or year .41 Economic implications o f different populations o f crawfish based on size distribution at harvest for crawfish production studies (1991 to 1996) Rice Research Station, Louisiana Agricultural Experiment Station, LSU Agricultural Center, Crowley, Louisiana .43 Mean (± SD) relative density estimates (crawfish/dip-net sweep) for Rice Research Station crawfish ponds grouped by % o f total yield (kg/ha) >21 g 44 Mean (± SD) relative density estimates (crawfisb/trapset) estimates for Rice Research Station crawfish ponds grouped by % o f total yield (kg/ha) >21 g 46 Summary o f selected mean environmental conditions after fiood-up for crawfish studies (1991 to 1996) Rice Research Station, Louisiana Agricultural Experiment Station, LSU Agricultural Center, Crowley, Louisiana 47 10 Comparison o f forage biomass values (g/m^ dry weight) over time for 1994 and 1995 crawfish production seasons Rice Research Station, Louisiana Agricultural Experiment Station, LSU Agricultural Center, Crowley, Louisiana 47 VI R ep ro d u ced with p erm ission o f th e copyright ow ner Further reproduction prohibited w ithout perm ission ... with permission of the copyright owner Further reproduction prohibited without permission EVALUATION OF SAMPLING GEAR FOR PREDICTING HARVEST SIZE, YIELD AND INCIDENCE OF STUNTING IN CRAWFISH PONDS.. . to determine the relationship among catch-per-unit-effort (CPUE) o f sampling gear (alone and in combination) with respect to yield in weight (kg/ha), yield in number (crawfish/ ha) and size distribution... original, b^inning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps Each original is also photogrqrhed in one exposure and is included in reduced