Neighborhood surveys
Dropping a bunch of fish condos into a lake sounds like a good idea — and it generally does amount to such. But determining which types of structures work best in particular areas requires analysis. This is where Clemson University’s efforts enter the picture.
Starting in 2016, Farmer’s team embarked on a mark and recapture study, which evaluates population estimates for largemouth bass in coves with and without habitat. This involves tagging bass with Passive Integrated Transponder (PIT) tags — RFID technology, which identifies a specific tagged fish by its unique 16-digit PIT tag number when scanned after recapture.
Basically, Clemson students tag a bunch of fish captured through electrofishing, revisit the same spots multiple times to resample and use the recapture data to build population estimates through individual capture histories.
“This is a joint project with the South Carolina DNR; they had one of their electrofishing boats out and we had our Clemson University electrofisher out with students,” Farmer said. “It was a great collaborative effort, because students (like Kerr) got to work side by side with state biologists, and we generated some data that was informative for management as well.”
Farmer said the mark and recapture study also uses surgically implanted acoustic telemetry tags. Emitting signals detectable by a portable listening device called a hydrophone, the tags allow his team to also track fish in deeper areas.
“A subset of the fish (captured through electrofishing) also has the telemetry tags, which allow us to understand if they were within 8 feet of the shoreline, or they were in deeper water,” Farmer said. “That told us the fraction of the population that was vulnerable to our electrofishing, and allowed us to generate more precise population estimates.”
More recently, 2021 saw Kerr launch a black bass habitat use and habitat selection project, which also uses telemetry tags. This effort includes largemouth and Alabama spotted bass.
Data driven
“Deon is doing some fine-scale tracking of (both species),” Farmer said. “When we tag them, we know what species it is and each tag is unique, so you can follow the fish around.
“He’s generating habitat use and habitat selection metrics, so he’ll have data on what depths, what habitats, what structures and what substrates both species are using. That data will then inform habitat enhancement efforts by the South Carolina DNR for optimal placement to benefit certain species.”
Complementing Clemson’s work, Chastain said the SCDNR conducts some of its own studies, mostly with the easily accessible cut-and-cable trees. Here, the agency assists Clemson with electrofishing, as these shallow lying structures make ideal targets for sampling bass, crappie and bluegill populations.
“When we’re electrofishing, they’re within our reach to see what’s there,” Chastain said. “On some of the deeper stuff, 10-15 feet deep, we can’t shock anything, so we have to look at different avenues to see what fish are there. That’s what Clemson helps us with — seeing if fish are on our structures or not.”
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