Electronic bass key to fish species’ conservation

By Marc Speir
University News Service
November 29, 2007

Anglers that fish the waters of the Pedernales River near Fredericksburg and the South Llano River near Junction may be in for a unique catch.

Associate professor Tim Bonner and aquatic biology graduate student Josh Perkin from Texas State University-San Marcos are electronically equipping one dozen Guadalupe bass in each river with radio telemetry tags for conservation purposes.

Guadalupe bass undergoing surgical process to be fitted with a telemetric device.

The Department of Biology is tracking the Guadalupe bass, a species in danger of extinction from habitat modification and crossbreeding with non-native smallmouth bass, by inserting electronic devices into the underbellies of the Guadalupe bass and recording their habitat and migration patterns.

Guadalupe bass that are used for the study will pull a small eight-inch antenna underneath their pelvic fins that will be used as a beacon to locate the fish and track behavior. The research will begin in late December and is expected to end in June, when devices will be removed from the bass.

Those catching “wired” fish are asked to return them to the water so the study can be completed with the most accurate information.

Perkin and Bonner will use data on the depth of the water, velocity of river current, temperature and other critical habitat conditions to help understand habitat needs. The information will guide the Texas Parks and Wildlife Department, among other organizations, in protecting the bass in areas where the Guadalupe bass are expected to thrive.

“We chose the South Llano and the Pedernales because a high abundance of genetically pure Guadalupe bass still exist,” Perkin, from Abilene , said. “We can collect information there that can be used in efforts to manage the fish in other rivers.”

Guadalupe bass after being fitted with a telemetric device.

Known as the state fish of Texas , Guadalupe bass are native and found only in Texas on the Guadalupe, Brazos , Colorado , Nueces and San Antonio rivers and their tributaries.

Texas Parks and Wildlife allocated funds for the research to conserve the bass and promote a diversity of species for anglers.

“These fish aren’t found anywhere else in the world but central Texas ,” said Perkin. “Fishermen find them to be a great sport fish because even though they’re small, they’re tough and aggressive.”

Bonner will also be working with Ph.D. student Preston Bean or Aledo in an area-wide genetic survey to reveal the level of introgression and crossbreeding within the Guadalupe bass population.

“We are testing the genetic diversity among all black basses within the historical range of Guadalupe bass to determine the status of genetically pure and introgressed populations,” said Bonner. “This way, we can see the extent of crossbreeding.”

Anglers from the Texas State community are concerned about the conservation efforts to support the state fish.

“What I’ve thought was a Guadalupe bass might not be a true one,” said Jerrett Kramer, geography-natural resource management graduate from Austin . “Since it is a native bass, it would be shame to see it gone.”