(Laterallus Jamaicensis) Prepared By: Am
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Final Report to: Texas Comptroller Texas Species Research IAC # 15-5545RR Black Rail (Laterallus jamaicensis) Photo: Black Rail at San Bernard NWR, 2017 (Credit: A. A. Moore) Prepared by: Amanda A. Moore Texas State University, San Marcos Department of Biology November 2018 Primary respondent: Dr. Floyd Weckerly Department of Biology, 601 University Drive, Texas State University, San Marcos, Texas 78666. E-mail: [email protected]; Phone: 512-245-3353 Co-respondent: Dr. M. Clay Green Department of Biology, 601 University Drive, Texas State University, San Marcos, Texas 78666. E-mail: [email protected]; Phone: 512-245-8037 Research Collaborator: James D. M. Tolliver Table of Contents Acknowledgements ......................................................................................................................... iv Summary.......................................................................................................................................... iv Introduction ..................................................................................................................................... 1 Chapter 1: Species distribution models for the Eastern Black Rail ................................................. 2 Introduction ................................................................................................................................. 2 Methods ...................................................................................................................................... 4 Study Area ............................................................................................................................... 4 Species occurrence data .......................................................................................................... 5 Modeling detectability and occupancy ................................................................................... 6 Results ......................................................................................................................................... 8 Discussion .................................................................................................................................. 11 Chapter 2: Radio Telemetry .......................................................................................................... 13 Introduction ............................................................................................................................... 13 Methods .................................................................................................................................... 14 Capture and Radio Marking ................................................................................................... 14 Radio Tracking ....................................................................................................................... 16 Statistical analyses ................................................................................................................. 17 Results ....................................................................................................................................... 18 Home Range .......................................................................................................................... 18 Habitat Selection ................................................................................................................... 19 Discussion .................................................................................................................................. 20 Chapter 3: Habitat selection of Black Rails and Yellow Rails in the context of fire ....................... 22 Introduction ............................................................................................................................... 22 Methods .................................................................................................................................... 24 Survey Methods ..................................................................................................................... 24 Vegetation Assessment ......................................................................................................... 25 Statistical analysis .................................................................................................................. 25 Results ....................................................................................................................................... 26 Discussion .................................................................................................................................. 30 Conclusion and recommendations ................................................................................................ 31 Literature Cited .............................................................................................................................. 32 i List of Figures Figure 1. Location of 6 study sites along the Texas coast where Black Rail call-playback surveys were conducted in 2015 and 2016 ...................................................................... 5 Figure 2. Predicted probabilities of occupancy (ѱ) for Black Rails in the coastal region of Texas as described by habitat covariates. ...................................................................... 10 Figure 3. Predicted probability of occurrence for the Black Rail in coastal Texas ........... 12 Figure 4. Location of areas at San Bernard NWR, Texas, where Black Rail radio telemetry study took place (2017-18) ............................................................................................. 16 Figure 5. Elevation at 243 relocations of radio-marked Black Rails captured at San Bernard NWR, Texas, winter and spring 2017 and 2018 ............................................... 20 Figure 6. Location of burn plots at San Bernard NWR, Texas, where Black Rails and Yellow Rails were captured and banded (2017-18) ....................................................... 24 Figure 7. Number of Black Rails and Yellow Rails captured in 2017 in 6 plots at San Bernard NWR, Texas, that differed in number of years since last burned .................... 26 Figure 8. Number of Black Rails and Yellow Rails captured in 2018 in 6 plots at San Bernard NWR, Texas, that differed in number of years since last burned .................... 26 Figure 9. Overhead cover measured in burn plots at locations were Black Rails and Yellow Rails were captured in 2017 and 2018 at San Bernard NWR, Texas .................. 28 ii List of Tables Table 1. Descriptionsfrom Elliott (2014) of ecotypes used as habitat covariates in occupancy models ............................................................................................................ 8 Table 2. Candidate models explaining Black Rail occurrence in the coastal region of Texas from 2015 to 2016 .................................................................................................. 9 Table 3. Predicted probability of occurrence of Black Rails within coastal Texas study region .............................................................................................................................. 12 Table 4. Untransformed regression coefficients for the covariates potentially affecting site occupancy (ѱ) and detection probabilities (푝) of Black Rails in coastal Texas in 20115 and 2016 .............................................................................................................. 13 Table 5. Means (±SD) of home range (95%) and core use area (50% kernel) of 14 radio- marked Black Rails captured at San Bernard NWR, Texas, winter and spring 2017 and 2018 ................................................................................................................................ 19 Table 6. Ecotypes within 95% MCP home ranges of 14 radio-marked Black Rails captured at San Bernard NWR, Texas, winter and spring 2017 and 2018. ................................... 20 Table 7. Dominant plant species in burn plots where Black Rails and Yellow Rails were captured in 2017 and 2018, San Bernard NWR, Texas................................................... 27 Table 8. Candidate models examining relative abundance of Black Rails and Yellow Rails in relation to average habitat covariates in burn-plots located at San Bernard NWR, Texas, winter 2017 and 2018 ......................................................................................... 29 iii Acknowledgements Many thanks to the U.S. Fish and Wildlife Service (especially Jennifer Wilson and Woody Woodrow), Texas Parks and Wildlife Department, and The Nature Conservancy biologists and refuge managers who facilitated our research. Data collection was made possible due to excellent field technicians: Tara Hohman, Christina Farrell, Jacob Rogers, Matthew Boone, Shelby Stanley, Bryan Baird, Madison Torres, Cameron Caldwell, Rebekah Rylander, Sara Durham, Joe Hohman, Heather Erickson, Joey Martinez, Matt Milholland, Bradford Westrich, Rebecca Bracken, and Ali Cappadonna. Funding for this research was provided by the Texas Comptroller and Texas Parks and Wildlife Department. Summary The enigmatic Black Rail (Laterallus jamaicensis) is often regarded as the most secretive marsh bird in North America. The Eastern Black Rail (L. j. jamaicensis) may be the most endangered bird species along the Atlantic and Gulf coasts of North America, as it is listed as endangered in six eastern states and is proposed