Researchers at the University of Georgia have identified and formally described two previously unrecognized species of black bass, known as Bertram bass and Altamaha bass, in a recently published study.
Although this species has only recently been officially classified, it has been observed before. Ecologist Bud Freeman first met Micropterus pupuginow called Bertram’s Bass, dates back to the 1980s. A couple visiting the Broad River showed him an unusual fish they had caught and kept in a cooler. Freeman immediately realized it was something different and offered them $5 to pick it up. They refused, saying, “No, we’re going to take it home and eat it.”
“It would have been an important specimen,” said Freeman, the study’s lead author and senior public servant emeritus associate professor emeritus at UGA’s Odum School of Ecology.
Over the next several decades, Freeman and his team collected samples from across the region. Bertram bass were collected from 14 locations in the Savannah and Saluda River watersheds, and Altamaha bass were collected from 14 locations in the Altamaha and Ogeechee River systems.
Unique physical characteristics and DNA evidence
Both species were once classified in the same group as the red bass, but closer inspection reveals distinct differences in appearance. Bertram bass exhibits a bright golden color with dark brown spots along the sides, a mottled abdomen, and a rosy tinge to the fins. They also have oval tooth patches and striking red eyes with black pupils framed by thin gold rings. These fish can reach 15 inches in length.
Altamaha bus, or Micropterus cariurusthe scales are also golden, but the edges are olive-colored and the markings on the sides are darker. Their fins have orange accents and small oval tooth patches. Like Bertram’s basses, they have red eyes with gold rings around the pupils and can grow to about 14 inches in length.
Beyond the visible characteristics, the research team conducted detailed genetic analysis to confirm the identity of the species.
“It used to be that you could go out and catch a fish, bring it in, count the scales, measure the tail, measure this and that, write a description, and that was it,” said study co-author Mary Freeman, an adjunct faculty member at the Odum School. “Now genetic characterization is also being done, in this case genetic characterization of all the individuals used to describe the fish to prevent the contamination of hybrid specimens.”
To ensure accuracy, the scientists analyzed mitochondrial DNA and used advanced bioinformatics tools to compare small segments of nuclear DNA. While the study references more than 100 specimens used to define the two new species, the broader dataset includes 570 fish across multiple bass species, including smallmouth, largemouth bass, northern spotted bass, shallow water, Tallapoosa, redeye, and Alabama bass.
“You’re laying the foundation for your future,” Mary Freeman said. “With hybridization, Bertram’s base may not exist as much as it used to, but we know what it was.”
Habitat change and hybridization risks
Bertram bass and Altamaha bass live in flowing river systems, usually in fast-moving areas near brinks and rocky areas. However, these environments have changed significantly over time due to the accumulation of sediment and the construction of dams that divide waterways.
Other introductions Micropterus Species living outside their natural ranges increase the risk of interbreeding. This species mixing could threaten the genetic integrity and long-term survival of these newly recognized basses.
“It’s important to name these evolutionarily distinct lineages,” says Bud Freeman. “By recognizing these species, we are recognizing how extrinsic barriers are being breached by human activities and how rapidly they are being lost.”
Origin of name and scientific publications
Freeman first proposed the name Bertram’s Bass in the 1990s. scientific name M. Pupagi This monument honors the Seminole Creek Tribe of Florida, whose chief gave William Bartram the name “Puck Puggy,” meaning “flower hunter.” During his travels from 1773 to 1776, Bertram explored areas inhabited by this species and recorded flora and fauna that were unfamiliar to early North American settlers.
Altamaha bus, or M. cariuruslater given its name. The term cariurus comes from the words meaning beautiful and tail.
This study zoo animalsincludes contributions from Kelly N. Petersen, Bryson G. Hilburn, and Mary C. Freeman of the Odum School of Ecology. John P. Wares of the Odum School and UGA Department of Genetics; Mark C. Scott of the South Carolina Department of Natural Resources. Natalia J. Bayona Vazquez, Oxford College of Emory University; Andrew T. Taylor of the University of North Georgia.
Funding for this research was provided through state wildlife competition grants awarded to the South Carolina Department of Natural Resources and the Georgia Department of Natural Resources.
