Development, Evaluation, and Application of Spatio-Temporal
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DEVELOPMENT, EVALUATION, AND APPLICATION OF SPATIO-TEMPORAL WADING BIRD FORAGING MODELS TO GUIDE EVERGLADES RESTORATION by James M. Beerens A Dissertation Submitted to the Faculty of The Charles E. Schmidt College of Science in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Florida Atlantic University Boca Raton, FL May 2014 ii ACKNOWLEDGMENTS Funding for this entire research project was provided by the U.S. Army Corps of Engineers. I was also supported through a scholarship from The Everglades Foundation and the Presidential Fellowship and Newell Doctoral Fellowship from Florida Atlantic University. First and foremost, I thank my advisor, Dr. Erik Noonburg, for the countless hours he contributed to the ideas underlying this dissertation. His availability and support helped provide a platform for the project to be a success. Dr. Dale Gawlik played an early and influential role in my development as an avian ecologist in the Everglades and provided the opportunity to continue the work that is my passion. Further, his appreciation for conservation and the natural world continue to provide a model for a good mentor. I also thank Dr. Brian Benscoter and Dr. Ed Proffitt for their contribution to my dissertation as committee members. Some of the most important people in this entire process are fellow scientists that have challenged my ideas and provided valuable feedback along my journey. I especially want to thank Mark Barrett, Bryan Botson, Mark Cook, and Peter Frederick for the time and effort they contributed to improving my quality of work. I also am grateful to Doug Donalson and Andy Loschiavo at the U.S. Army Corps of Engineers for their dedication to this project and willingness to trust my vision in representing how wading birds interact with a changing world. iii I thank Thomas Bancroft, Sonny Bass, Marty Fleming, Wayne Hoffman, Dave Nelson, Jim Shortemeyer, and all the other people who spent numerous hours in small planes collecting valuable wading bird data. I also am indebted to Paul Conrads, Heather Henkel, Aaron Higer, Pamela Telis, and the Everglades Depth Estimation Network (EDEN) team for their dedication to provide a high resolution hydrology model for the Everglades. Leonard Pearlstine was instrumental in providing the appropriate hydrology data from the Regional System Model (RSM) and South Florida Water Management Model (SFWMM) that contributed to the applications in this project. I am sincerely thankful to my family for their love and the value system they instilled in me from a young age. They called me to continually look out into the world and speak for those without a voice. Under increasing pressure from human development, countless plant and animal species have precipitously declined. It is our call as environmental scientists to accurately portray this change to plan for a sustainable future. Consequently, I also thank the birds for their incredible ability to adapt to human- created challenges and hold on as we correct some of the ecological mistakes from our past. Finally, I thank my wife Maria for enduring the long hours of a graduate student, and for being a sounding board and skillful editor. She has stood by me through my hardest challenges and I am forever grateful for her inspiration in my life. This dissertation has greatly benefited from her selflessness, grace, and humor. iv ABSTRACT Author: James M. Beerens Title: Development, Evaluation, and Application of Spatio-Temporal Wading Bird Foraging Models to Guide Everglades Restoration Institution: Florida Atlantic University Degree: Doctor of Philosophy Dissertation Advisor: Dr. Erik. Noonburg Year: 2014 In south Florida, the Greater Everglades ecosystem supports sixteen species of wading birds. Wading birds serve as important indicator species because they are highly mobile, demonstrate flexible habitat selection, and respond quickly to changes in habitat quality. Models that establish habitat relationships from distribution patterns of wading birds can be used to predict changes in habitat quality that may result from restoration and climate change. I developed spatio-temporal species distribution models for the Great Egret, White Ibis, and Wood Stork over a decadal gradient of environmental conditions to identify factors that link habitat availability to habitat use (i.e., habitat selection), habitat use to species abundance, and species abundance (over multiple scales) to nesting effort and success. Hydrological variables (depth, recession rate, days since drydown, reversal, and hydroperiod) over multiple temporal scales and with existing links to wading bird responses were used as proxies for landscape processes that v influence prey availability (i.e., resources). In temporal foraging conditions (TFC) models, species demonstrated conditional preferences for resources based on resource levels at differing temporal scales. Wading bird abundance was highest when prey production from optimal periods of wetland inundation was concentrated in shallow depths. Similar responses were observed in spatial foraging conditions (SFC) models predicting spatial occurrence over time, accounting for spatial autocorrelation. The TFC index represents conditions within suitable depths that change daily and reflects patch quality, whereas the SFC index spatially represents suitability of all cells and reflects daily landscape patch abundance. I linked these indices to responses at the nest initiation and nest provisioning breeding phases from 1993-2013. The timing of increases and overall magnitude of resource pulses predicted by the TFC in March and April were strongly linked to breeding responses by all species. Great Egret nesting effort and success were higher with increases in conspecific attraction (i.e., clustering). Wood Stork nesting effort was closely related to timing of concurrently high levels of patch quality (regional scale) and abundance (400-m scale), indicating the importance of a multi-scaled approach. The models helped identify positive and negative changes to multi-annual resource pulses from hydrological restoration and climate change scenarios, respectively. vi DEVELOPMENT, EVALUATION, AND APPLICATION OF SPATIO-TEMPORAL WADING BIRD FORAGING MODELS TO GUIDE EVERGLADES RESTORATION LIST OF TABLES ...............................................................................................................x LIST OF FIGURES .......................................................................................................... xii CHAPTER 1: INTRODUCTION ........................................................................................1 INTRODUCTION ....................................................................................................... 1 LITERATURE CITED ........................................................................................................7 CHAPTER 2: ANALYSIS OF HABITAT USE ...............................................................10 METHODS ................................................................................................................ 10 RESULTS AND DISCUSSION ................................................................................ 12 Depth .................................................................................................................. 12 Recession Rate .................................................................................................... 16 Prey Production and Days since Drydown ......................................................... 20 LITERATURE CITED .............................................................................................. 21 CHAPTER 3: MODELING SPATIO-TEMPORAL RESPONSES OF WADING BIRD INDICATOR SPECIES ACROSS RESOURCE GRADIENTS FOR EVERGLADES RESTORATION.....................................................................................25 ABSTRACT .............................................................................................................. 25 INTRODUCTION ..................................................................................................... 26 METHODS ................................................................................................................ 32 Data and Variables ............................................................................................. 32 Identifying Available Habitat ............................................................................. 34 Temporal Foraging Conditions (TFC; Patch Quality) ........................................ 34 Spatial Foraging Conditions (SFC; Patch Abundance) ...................................... 36 RESULTS .................................................................................................................. 37 Identifying Available Habitat ............................................................................. 37 vii Depth Use ........................................................................................................... 38 Recession Rate Use ............................................................................................ 39 Days since Drydown Use ................................................................................... 40 Temporal Foraging Conditions (Patch Quality) ................................................. 41 Spatial Foraging Conditions (Patch Abundance) ............................................... 42 DISCUSSION ...........................................................................................................