Genetic survey could determine status of endangered songbird

A Texas A&M scientist’s two-year genetic survey of a Texas songbird—the golden-cheeked warbler—could determine its status on a federal endangered species list.

Giri Athrey, an AgriLife Research avian geneticist in College Station, worked on the previous golden-cheeked warbler study in 2006-09 and is conducting the survey, which began May 24. He is an assistant professor in the Department of Poultry Science, College of Agriculture and Life Sciences.

The golden-cheeked warbler has been a species of conservation interest in Texas for a very long time, Athrey said. They are the only neotropical warblers that breed and nest exclusively in Texas.

The U.S. Fish and Wildlife Service periodically reviews evidence supporting the continued listing or delisting of the species since its classification as endangered in 1990. Athrey was selected to generate data necessary for the next review of the golden-cheeked warbler throughout its habitat in Central Texas.

The two-year project is funded by the Department of Defense via the Army Corps of Engineers. To conduct the study, Athrey and collaborators with the city of Austin will undertake a broad-scaled genetic survey of the species using the latest genomics and bioinformatics approaches.

“Along the way, we will also assemble the genome of this species, which will be the first endangered songbird in the mainland United States whose genome will be assembled,” he said. “We will be conducting the analysis using the latest genomics approaches to assess the species’ recovery and generate knowledge that will inform the listing and management decisions in the near future.

“We will be using whole-genome data for this study,” he continued. “The advantage in this case would be that we can assess if and how genetic diversity in functionally important genes, such as genes related to immunity, are impacted. With that data, we can make inferences regarding what the recovery means for survival and long-term viability.”

The Fish and Wildlife Service did not find sufficient evidence to support delisting the last time a review was performed, Athrey said. Genetic data is a critical component for conservation and management decision-making, and these approaches have become ubiquitous around the world, he said.

The last genetic study on golden-cheeked warblers, published in 2012, showed there had been a steep decline in genetic diversity of the golden-cheeked warbler due to habitat loss experienced over the last century.

“We’ll be looking at the genetic diversity and structure of the species because Fish and Wildlife wants to determine whether to look at the species as one large contiguous population or independent units, from a management perspective,” Athrey said. “Recovery of the species is the goal everyone is working towards. Various approaches are used to assess progress on recovery goals, and genetics is one of them.

“This study is likely to be crucial in determining how the golden-cheeked warbler may be managed in the future and what protections need to be afforded it.”