Black Bass Conservation
There are five species of black bass inhabiting Florida's fresh waters. Here, you can find information on the lesser known spotted, shoal, Suwannee and Choctaw basses.
The Choctaw bass, which was long mistaken for spotted bass, is found in coastal rivers along the Florida Panhandle and southern Alabama.
Sometimes organisms are so similar in appearance that members of two different species are considered to be the same species. This was the case for a newly discovered member of the black basses – the Choctaw bass, Micropterus haiaka. For decades, biologists and anglers had not realized this bass, which inhabits coastal river systems in the western Florida Panhandle and Alabama, was actually distinct from one of its relatives, the spotted bass.
If not for a Fish and Wildlife Research Institute (FWRI) genetic study involving other basses of the genus Micropterus, Florida’s newest native bass species might have eluded detection even longer. While testing specimens from northwest Florida’s Chipola River in 2007, FWRI scientists encountered a DNA profile that did not belong to any known bass species. To locate its source, they began testing archived bass tissues collected from nearby rivers.
By early 2009, scientists had discovered the same genetic profile in bass populations inhabiting the Choctawhatchee, Yellow, Blackwater, Escambia, Conecuh and Perdido rivers. After reinterpreting work done in 1940 by taxonomists Carl Hubbs and Reeve Bailey, scientists believe Choctaw bass could also occur in extreme southwest Alabama and southeast Mississippi, just west of the Mobile River Basin. Since 2012, they have been working to confirm this.
The scientific criteria for recognizing a new species are rigorous and the formal taxonomic (classification) process is ongoing. Fortunately, the genetic and morphological (regarding form and structure) evidence assembled by the FWRI research team leaves little doubt that fish with this new genetic profile constitute a valid species. Choctaw bass can usually be distinguished from other basses by counting scales, fin rays and gill rakers, which are comblike projections inside the gills that prevent particles from collecting on the gill filaments. Foolproof identification, however, requires genetic testing.
The name recommended for this new species – Choctaw bass – reflects its geographic connection to the indigenous range of the Native American Choctaw tribe. The provisional scientific designation “haiaka” comes from the Choctaw language and means “revealed” or “manifest.” Researchers believe it is a fitting label as they did not set out to discover a new bass species.
Now that this native bass is known, scientists want to ensure the population remains healthy by implementing the best possible conservation management practices. Ironically, the biggest conservation threat to the Choctaw bass may come from its cousins, spotted bass and Alabama bass. Typically, Choctaw bass have been found in the upper reaches of rivers and streams where sediment accumulates, avoiding stream headwaters and tidal zones found closer to the coast. As of late 2012, everywhere Choctaw bass had been collected, spotted bass and Alabama bass were absent. This is encouraging because these bass species are often introduced outside of their native range to expand fishing opportunities, which can displace native bass populations in other freshwater systems and, in some cases, allow introduced species to genetically overtake native basses through hybridization (interbreeding). Florida and Alabama now have regulations preventing fish introductions and relocations.
Additional information may be found in the following publications:
Hubbs C.L., Bailey R.M. 1940. A revision of the black basses (Micropterus and Huro) with descriptions of four new forms. Miscellaneous Publications Museum of Zoology University of Michigan 48: 19-22.
Tringali M.D., Barthel B.L., Seyoum S., Knight J.R. In review. Molecular and Morphological Evidence for a Novel Black bass Species Native to Rivers of the East Gulf Coastal Plain. In: Tringali MD, Allen MS, Birdsong T, Long JM (eds.). Black Bass Diversity: Multidisciplinary Science for Conservation. Proceedings of the Symposium Black Bass Diversity: Multidisciplinary Science for Conservation, Nashville, TN, February 8-10, 2013. American Fisheries Society, Bethesda, MA.
Biologists report the results of a study investigating shoal bass spawning behavior and habitat in the Chipola River.
Fish and Wildlife Research Institute (FWRI) researchers have gathered important information about shoal bass (Micropterus cataractae) spawning behavior and habitat. These observations will be useful in determining management strategies that benefit this vulnerable species, its habitat and the anglers who fish for it.
The shoal bass is one of four black bass species native to Florida, and Florida’s Wildlife Legacy Initiative lists it as a species of greatest conservation need. The Endangered Species Committee of the American Fisheries Society lists the shoal bass as a vulnerable species because of its limited range – a few rivers systems in Alabama, Florida and Georgia. The only known reproducing population in Florida is located in the Chipola River in the northwest region of the state.
To learn how to better protect the shoal bass population in Florida, scientists conducted a study in the Chipola River to evaluate spawning behaviors and environmental factors that affect spawning success. They documented and captured on film for the first time the following:
- spawning behavior
- parental guarding of eggs
- eggs hatching
- maturation of hatched fry
- predation by other fish species
Biologists collected data in 2011 and 2012, from mid-April to mid-May, by surveying 6.5-mile stretch of the river for male shoal bass guarding beds (nests). FWRI researchers recorded 97 bed locations over the course of the two-year study. Each time a bed was located, they recorded water temperature and velocity, water depth and habitat type.
Researchers found shoal bass typically lay between 300 and 2,000 eggs per bed, which is the lowest number for any black bass species. Eggs hatched into fry 5-6 days after being laid. The study showed the number of hatched fry – ranging from 15 to 1,293 – varied greatly among beds.
A group of these predators can significantly deplete the number of eggs, especially when the male shoal bass leaves the nest for even a short period of time.
The results of this study highlight the importance of shoal and shallow bedrock habitats in the Chipola River. Researchers will use the information to identify additional areas of high-quality shoal bass spawning habitat along the entire Chipola River.
Beds were located on limestone bedrock in water 1.5-6 feet deep, with temperatures ranging from 66 to 78 degrees Fahrenheit. These differences in depth and temperature were not found to have an effect on spawning success. Researchers also noticed eel grass (Vallisneria americana) and boulders were often located adjacent to shoal bass beds.
Researchers expected water velocity to be a major factor influencing spawning success, and preliminary results suggest beds located in areas with lower flow velocity contained more eggs and more hatched fry on average. Scientists think one possible reason for this is beds located in areas with faster currents may be subjected to higher densities of an unexpected predator species, blackbanded darters (Percina nigrofasciata).
FWRI biologists work to preserve the genetic purity of Florida’s premier freshwater sport fish.
Florida bass, Micropterus floridanus, have a small natural range; they are only native to peninsular Florida. This species grows larger than any other black bass, which is a big part of the reason they are the premier freshwater sport fish in Florida. Recognizing the ecological and economic value of genetically-pure Florida bass, FWRI biologists conduct research to help prevent these bass from mating and producing hybrid offspring with non-native northern largemouth bass,M. salmoides.
The taxonomy of these two bass sparked a debate amongst scientists for more than a decade. The Florida bass and the northern largemouth bass look very similar, but do they represent different species or subspecies? They were originally described as subspecies of largemouth bass in 1949 and the American Fisheries Society (AFS) has continued to use this terminology – until recently. Many scientists have become convinced that the Florida bass is a distinct species based on genetic, behavioral, and environmental preference/tolerance differences.
During a statewide genetics study, scientists analyzed bass collected from 48 lakes and rivers throughout Florida. The sampled water bodies included populations of pure Florida bass and intergrade (or crossbred) populations where Florida and northern largemouth bass mixed or hybridized. Populations of pure Florida bass were found south of the Suwannee River, while intergrade populations were located in northern and western parts of the state. This led the FWC to amend a rule to designate pure northern largemouth bass as a conditional species (dangerous to native ecosystems) south and east of the Suwannee River. This was intended to prevent this non-native species from being moved into the range of pure Florida bass in peninsular Florida by anglers, private pond owners, or fish dealers.
The FWC is dedicated to preserving the long-term well-being of fish and wildlife resources. To that end, the agency designated four geographic regions of the state as Florida bassGenetic Management Unitsafter research indicated that bass in each area had unique genetic compositions. When FWC is stocking hatchery bass or relocating wild-caught bass, fisheries managers avoid transporting bass betweenGenetic Management Unitsto avoid mixing gene pools. FWC takes this precautionary approach when moving bass because research has shown that fish have adaptations that help them survive and reproduce in the environments in which they naturally occur.
Biologists collect tissue samples from fish in the wild and at the hatchery and send them to the FWRI fisheries genetics laboratory for analysis. Geneticists at FWRI developed a set of molecular markers that are able to effectively identify each species of black bass and detect individuals that have hybrid ancestries. The geneticists work with the Richloam Fish Hatchery staff at the Florida Bass Conservation Center to conduct genetic testing that makes sure that only pure Florida bass are allowed to spawn at the hatchery. This ensures that only pure Florida bass are released into water bodies during stockings. Geneticists are also able to determine whether a bass collected by a biologist in the wild was produced at the hatchery. Resource managers can use this information to determine the survival rate and contribution of hatchery fish after stocking.
Since its creation, the bass genetics project has expanded to include research on all the black bass species that are native to Florida, including Suwannee bass, shoal bass, and the newly classified Choctaw bass. These studies will provide resource managers with information they can use to protect the genetic integrity of native species by preventing or minimizing the chance of hybridization with invasive species.
This program was designated as a high priority by fishery managers in FWC’s Florida Black Bass Management Plan. Fisheries agencies in other states also promote black bass conservation, but FWC’s Florida Bass Conservation Program is by far the most comprehensive genetic conservation and management program for black bass in the country.