ABSTRACT RABON, DAVID REID, JR. Factors Affecting Reproduction in the Red Wolf ( Canis rufus ). (Under the direction of Dr. Harold F. Heatwole). The endangered red wolf ( Canis rufus ) was preserved in captivity with just 14 founders following its planned extirpation in the wild. Longitudinal reproductive events were investigated to determine whether inbreeding, parental age, and breeding experience were factors in reproductive performance and fitness. A behavioral preference study using olfactory presentations of conspecific and congeneric social odors also was conducted to determine those factors that are important in the selection of mates. Over 30 years of managed breeding, the level of inbreeding in the captive population has increased, and litter size has declined. Inbreeding levels were lower in sires and dams that reproduced than in those that did not reproduce, but there was no difference in the level of inbreeding of actual and predicted litters. Litter size was negatively affected by offspring and paternal levels of inbreeding, but the effect of inbreeding on offspring survival was restricted to a positive influence. Younger wolves were more likely to reproduce, and were more likely to produce larger litters, than were older individuals. The age of the dam, but not the sire, had a significant negative effect on pup survival. Sires and dams that had prior experience in the production of offspring were more likely to reproduce again than were individuals without prior reproductive success, but prior sexual experience alone was not a factor in the production of offspring. Parental breeding experience had a significant negative effect on pup survival, but no apparent relationships with size or sex ratio of the litter. In general, females responded to the presentation of social odors of conspecific males more quickly than did males, and males responded more quickly to social odors of conspecific females than did females. There were no differences in the proportion of time males and females spent proximal to conspecific social odors. Males and females typically responded more quickly to and spent more time investigating social odors during the non- breeding season than during the breeding season. Species-specific responses to social odors were indeterminate. Factors Affecting Reproduction in the Red Wolf ( Canis rufus ) by David Reid Rabon, Jr. A dissertation submitted to the Graduate Faculty of North Carolina State University in partial fulfillment of the requirements for the Degree of Doctor of Philosophy Zoology Raleigh, North Carolina 2009 APPROVED BY: __________________________________ __________________________________ Dr. Harold F. Heatwole Dr. Phillip D. Doerr Committee Chair __________________________________ __________________________________ Dr. Nicholas M. Haddad Dr. Kenneth H. Pollock DEDICATION To Tracy. ii BIOGRAPHY David Reid Rabon, Jr. was born in Charlotte, North Carolina, to David and Dianne. In his youth, David spent numerous hours exploring urban streams and riparian corridors. After graduating from Independence High School, David started ascending the “corporate ladder,” completing an Associate of Arts degree from Central Piedmont Community College along the way. Although he enjoyed the benefits of a steady paycheck, the corporate life could not satisfy David’s interest in animal behavior and wildlife conservation. David entered the University of North Carolina at Wilmington to “formally” study the natural world, and graduated with Bachelor of Arts degrees in Biology and Psychology, and a Master of Science degree in Biology. Upon completion, David continued his graduate studies in Ontario Veterinary College’s Department of Biomedical Sciences at the University of Guelph before entering the doctoral program in the Department of Biology at North Carolina State University. David began his career in federal service with the U.S. Army Corps of Engineers, where he worked as a field biologist in the Regulatory Division. In 1999, David transferred to the U.S. Fish and Wildlife Service where he works as an endangered species biologist in the Division of Ecological Services. David’s current position has allowed him to work with a variety of endangered wildlife, including sea turtles, the piping plover, the Cape Fear shiner, and, of course, the red wolf. David currently holds memberships in several professional societies, including American Society of Mammalogists and Animal Behavior Society. He also was appointed iii membership in PSI CHI, the National Honor Society in Psychology, and Sigma Xi, the International Honor Society for Science and Engineering. iv ACKNOWLEDGMENTS It goes without saying that this research would not have been possible without the assistance, guidance, and support of many people. I cannot possibly name them all, for which I apologize, but I must recognize a few for the crucial role that they played in my completion of the doctoral program. I am deeply grateful to my committee – Drs. Hal Heatwole, Phil Doerr, Nick Haddad, and Ken Pollock – for their instruction, guidance, and support of this project. I am especially thankful for their patience and understanding of a student trying to complete a doctoral degree while maintaining a (sometimes) demanding full-time job. Special thanks to Dr. Heatwole for accepting me as a student and letting me pursue a project that may appear peripheral to his many areas of interest and expertise. Will Waddell, Red Wolf SSP Coordinator (Point Defiance Zoo & Aquarium) and member of the Red Wolf Recovery Implementation Team, provided direction, advice, and friendship during the course of my project. Simply, it was a privilege to work with Will. His contribution to this research and the red wolf recovery program was, and continues to be, immeasurable. To the entire staff of the Red Wolf Recovery Program, and especially Bud Fazio (former Team Leader), Art Beyer, and Diane Hendry, I give a mighty heartfelt “thank you.” This project would never have materialized without Bud’s support. Art tolerantly accepted and kindly responded to all of my inquiries for data, logistical support, and his professional opinion. Diane provided assistance and encouragement throughout my study. To Chris v Lucash, Ford Mauney, Michael Morse, Ryan Nordsven, and Kathy Whidbee, I thank you for your service and assistance. However, I am most thankful for the friendship you have given me. I greatly appreciate the assistance provided by the curatorial and management staff at the North Carolina Zoological Park. Specifically, Randy Fulk, Curator of Education (former Curator of Conservation and Research and former Red Wolf SSP Small Populations Manager), provided substantial guidance and advice, and Tim Mengel, retired Animal Management Supervisor, and Chris Lasher, Animal Management Supervisor, accommodated my every request to access the wolves. I also thank keepers Bob Blohme; Hannah Decker; Holly Payne; Amy Polanecki; Matt Randles; and, Kelly Wright, as well as Lorraine Smith, Mammal Curator (former), for their assistance. I devised and initiated this project under the direction of Dr. Karen Goodrowe (Curator, Point Defiance Zoo & Aquarium). I am grateful for the opportunity to have studied under her at the University of Guelph, however brief the time, but I am especially appreciative of the comments and advice that she provided once I was no longer her student. Appreciation is extended to Dr. Fred Knowlton (Red Wolf Recovery Implementation Team member; USDA, National Wildlife Research Center research biologist; and Utah State University emeritus professor) for providing coyote urine. Dr. Knowlton, as well as Drs. Michael Stoskopf, Karen Beck, Todd Fuller, Dennis Murray, and Lisette Waits of the Red Wolf Recovery Implementation Team, provided valuable feedback during the early stages of my project. vi Bob Pendergrass, Nature Center Supervisor (Dan Nicholas Park, Salisbury, NC), David Jones, Naturalist (Dan Nicholas Park, Salisbury, NC), Lisa New, Animal Collections Director/Mammals and Birds (Knoxville Zoological Gardens, Knoxville, TN), and Jennifer Manrod, Intern Coordinator/Conservation Biologist (Knoxville Zoological Gardens, Knoxville, TN), kindly accommodated my requests for access to wolves within their respective facilities. I am grateful for the administrative assistance provided by Meredith Henry and Susan Marschalk. Although I was not a physically located in David Clark Labs during my study, they always kept me informed. I also thank my (former) fellow graduate students, Drs. Becky Bartel and Allison Leidner, for their general advice and guidance on navigating the Department. This research was made possible by funding from the U.S. Fish and Wildlife Service and grants from the Point Defiance Zoo & Aquarium and the North Carolina Zoological Society. I am immensely grateful for their financial contributions. I also am indebted to my employer (U.S. Fish and Wildlife Service), and specifically my current (Pete Benjamin) and former (Dr. Garland Pardue) supervisors, for accommodating my desire to pursue a doctoral degree. Special thanks to all of my co-workers, and specifically Dale Suiter, Patty Matteson, and Dr. Tom Augspurger, for their assistance. I am thankful to my parents for their love and encouragement. Their belief in me and what they think I am capable of accomplishing is motivating. Lastly, but certainly not least, I thank my wife, Tracy. Her contribution to this dissertation is untold; she provided infinite support, unwavering devotion, and incalculable patience