programs Natural Resources

Eastern Black Rail

(Laterallus jamaicensis jamaicensis)

Background

The eastern black rail is listed as endangered by six eastern states, and the U.S. Fish and Wildlife Service (FWS) has proposed to list it as threatened with a Section 4(d) rule under the Endangered Species Act (ESA). The 4(d) rule would exempt some activities from take prohibitions in the ESA, including mowing and maintenance activities. The red-eyed, sparrow-sized bird lives in remote wetlands of the Midwest and along the coasts of the Atlantic and Pacific oceans and the Gulf of Mexico. Because it only comes out at night, prefers to walk hidden in tall grasses instead of fly and rarely makes a call, very little is known about its behavior and habitat needs.

Research Description

In 2014, the Texas Comptroller of Public Accounts (CPA) contracted with Texas State University to explore new ways to find black rails and determine influences on where it lives and abundance across the species’ range in Texas.

From east of Galveston Bay to west of Matagorda Bay, researchers conducted research to identify black rail individuals by playing recorded calls and determining the types of areas where the birds were found. They attached radio collars to adult black rails in the San Bernard National Wildlife Refuge to estimate home ranges and habitat selection of individual birds. Researchers also examined potential competition with other rail species by studying the abundance of various species over time and the different effects that various land management practices, such as the use of prescribed fire for controlling brush in grasslands, had on each species.

Because marsh habitat is extensive along the Texas coast, researchers surveyed six sites where eastern black rails may exist to model other suitable habitat along the coast. This model was created using data from call-playback surveys. The study will help inform interested parties where the bird is likely to be found or could potentially be reintroduced.

The researchers determined that eastern black rails prefer marsh habitats with large amounts of herbaceous vegetative cover but sparse woody cover.

Deliverables Received at Contract End, Oct. 31, 2018

  • Gather data from all surveys
  • Report and analyze survey results to estimate:
    • presence and persistence of populations surveyed
    • home ranges of the Texas populations
    • habitat selections within home ranges for Texas coastal populations

Why This Research Matters

Texas State University’s model and survey work addressed vital data gaps to inform the species status assessment and potential voluntary conservation measures. The results show a large enough amount of suitable eastern black rail habitat along the Texas coast to support a stable population. This finding helps establish Texas’ role in preserving the species and provides valuable information for the development of long-term planning for the coast for everything from storm water barriers to the expansion of cities. In partnership with Texas Parks and Wildlife Department, CPA helped organize meetings with stakeholders and agencies from multiple states to share research findings, help with the FWS Species Status Assessment and encourage discussions about developing a conservation strategy for the species.