FALL MIGRATION ECOLOGY OF AMERICAN WOODCOCK IN THE CENTRAL REGION OF THE UNITED STATES FALL MIGRATION ECOLOGY OF AMERICAN WOODCOCK IN THE CENTRAL REGION OF THE UNITED STATES A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science By NICHOLAS ANTHONY MYATT, B.S. Northland College, 2002 August 2004 University of Arkansas This thesis is approved for Recommendation to the Graduate Council Thesis Director: ______________________ David G. Krementz Thesis Committee: ______________________ W. Fredrick Limp ______________________ Kimberly G. Smith THESIS DUPLICATION RELEASE I hereby authorize the University of Arkansas Libraries to duplicate this thesis when needed for research and/or scholarship. Agreed___________________________ Refused__________________________ ACKNOWLEDGMENTS I would like to thank everyone who made my research possible. Dr. David Krementz, my major advisor, provided advice and support throughout my project, as well as provided me with an excellent start to a career in wildlife management and ecology. Dr. Fred Limp and Dr. Kimberly Smith provided valuable help while serving on my thesis committee. This project was made possible through funding from the U.S. Fish and Wildlife Service – Region IV and the Biological Resources Division of the U.S. Geological Survey. I especially thank Dr. David Andersen, Dr. Scott Lutz, Dr. John Bruggink, Kevin Doherty, Jed Meunier, Eileen Oppelt and their field crews who captured and radio-marked woodcock, and provided information on departure dates. Housing was provided by Swan Lake National Wildlife Refuge (NWR), Two Rivers NWR, Marais de Cygnes NWR, Mingo NWR, Lower Hatchie NWR, and St. Catherine Creek NWR. I would also like to thank my pilot Jimmy Goad for his incredible abilities to withstand endless hours of aerial radio telemetry and for his flexibility to my constantly changing schedule. This project would not have been as enjoyable without the help and support from my fellow graduate students at the Arkansas Cooperative Fish and Wildlife Research Unit. I would also like to thank Alicia Korpach who conducted a pilot season before I began at the Co-op Unit. I would not have been able to complete the GIS portions of this project without the technical support of John Wilson. Lastly, I would like to thank my fiancé Jill Babski who has always provided an endless supply of support and put up with my constant absence during many field seasons. iv TABLE OF CONTENTS Page CHAPTER 1: Introduction--------------------------------------------------------------------- 1 Literature Cited-------------------------------------------------------------------------- 9 Figures------------------------------------------------------------------------------------ 14 CHAPTER 2: Fall migration of American woodcock using Central --------------------- 16 Region band recovery and wing receipt data Abstract----------------------------------------------------------------------------------- 17 Introduction------------------------------------------------------------------------------ 17 Methods ---------------------------------------------------------------------------------- 18 Migration Progression -------------------------------------------------------------- 19 Migration Direction and Destination --------------------------------------------- 19 Results------------------------------------------------------------------------------------ 20 Migration Progression -------------------------------------------------------------- 20 Migration Direction and Destination --------------------------------------------- 21 Discussion---------------------------------------------------------------------------- 21 Management Implications---------------------------------------------------------- 24 Literature Cited-------------------------------------------------------------------------- 25 Figures------------------------------------------------------------------------------------ 27 CHAPTER 3: Fall migration rates, routes, and habitat use of American --------------- 67 woodcock in the Central Region v Abstract ------------------------------------------------------------------------------------ 68 Introduction ------------------------------------------------------------------------------- 68 Study Area--------------------------------------------------------------------------------- 72 Methods------------------------------------------------------------------------------------ 73 Capture --------------------------------------------------------------------------------- 73 Telemetry ------------------------------------------------------------------------------ 74 Habitat---------------------------------------------------------------------------------- 76 Results ------------------------------------------------------------------------------------- 78 Sample Size---------------------------------------------------------------------------- 78 Telemetry ------------------------------------------------------------------------------ 79 Migration Distance ------------------------------------------------------------------- 80 Stopover Duration -------------------------------------------------------------------- 80 Migration Habitat --------------------------------------------------------------------- 80 Winter Habitat------------------------------------------------------------------------- 82 Fall Migration Routes ---------------------------------------------------------------- 82 Potential Habitat Map ---------------------------------------------------------------- 83 Discussion --------------------------------------------------------------------------------- 83 Management Implications --------------------------------------------------------------- 90 Literature Cited --------------------------------------------------------------------------- 92 Figures ------------------------------------------------------------------------------------- 97 Tables -------------------------------------------------------------------------------------- 115 vi CHAPTER 1 INTRODUCTION The American woodcock, Scolopax minor, is a popular, migratory game bird throughout the eastern half of the United States, annually providing an estimated 3.4 million days of recreational hunting (U.S. Department of Interior 1988). Woodcock population management is separated into two management units, the Eastern and Central Regions (Coon et al. 1977) (Fig. 1). The U.S. Fish and Wildlife Service monitors woodcock populations in each region using a series of singing ground surveys that exploit the courtship display of male woodcock on breeding grounds. Each randomly selected survey route is sampled annually during peak seasonal courtship activities. Population indices are calculated using average number of singing woodcock per route, weighted for land area (Tautin et al. 1983). Since annual surveys began in 1968, population indices have annually declined 2.3% in the Eastern Region and 1.8% in the Central Region (Kelley 2003). Breeding population indices were the lowest in 1997 in the Central Region and 1995 in the Eastern Region (Kelley 2003). Widespread habitat alteration and loss caused by human development and forest succession are thought to be the primary causes of woodcock population declines. In the northeastern United States, hardwood seedling-sapling stand area has decreased by 26% over the last 20 years (Desseckar and Pursglove 2000). Furthermore, the total area of aspen (Populus spp.) forest in Minnesota, Michigan and 1 Wisconsin has decreased by 21% since the mid-1960s (Desseckar and Pursglove 2000). In the U. S., the largest concentration of bottomland hardwood forest, primary woodcock wintering habitat, occurs in the Lower Mississippi Alluvial Valley (MAV). Until the 1930s, the MAV has remained largely untouched and undeveloped due to seasonal flooding. Extensive reduction and degradation has taken place since that time, largely due to water control, which was followed by land clearing (Newling 1990). From the 1950s to 1970s, bottomland hardwood forests were lost at a rate exceeding 120,000 ha per year (MacDonald et al. 1979). Of the original 10 million hectares of bottomland hardwood forest in the MAV, 7.2 million hectares have been cleared for agriculture (King and Keeland 1999). Although hunting is not considered to be a major cause of woodcock population declines, the U.S. Fish and Wildlife Service restricted hunting in the Eastern Region in 1985, with additional restrictions in the Eastern and Central Regions in 1998 (Woehr 1999). These restrictions included a reduction from a 65- day hunting season and a 5-bird limit to 45 days in the Central Region and 30 days in the Eastern Region, each with a 3-bird limit (Kelley 2003). Woodcock population indices continue to decline despite reductions in season length and daily bag limit. Little research has been conducted on the fall migration ecology of this species. Although the timing of departure from the breeding grounds and arrival on the wintering grounds has been documented, little is known about what happens during the migration period. To effectively manage woodcock, managers need to consider fall migration habitat use, timing, and routes. 2 The woodcock range is restricted to the eastern half of North America south of the Taiga (Keppie and Whitting 1994). In the Central Region, woodcock primarily breed in the states and provinces surrounding the Great Lakes, but woodcock have been documented breeding in low densities as far south as Louisiana. Woodcock primarily over-winter