Fauna: Moxostoma robustum

Image by Duane Raver

Moxostoma robustum
Robust redhorse

Once thought to be extinct, the robust redhorse has been rediscovered and stocked in a few waterways, including the Ogeechee River. Missing from the scientific record for 122 years, it was conclusively identified again in 1991. 

A sizable fish, they can be up to 17 pounds and live nearly 30 years. They are in the sucker family and eat bivalves, using strong teeth for crushing and grinding. This is especially helpful to natural populations as they will consume the invasive species of Asiatic clam. However, the fish will also consume aquatic insects.

via GA DNR

With such a gap in the known history of the animal, scientists are still learning about the species. They seem to require still or slow-moving areas with gravel or silty beds for spawning. Once they reach adulthood, they prefer to live in riverbanks with woody treefall or branches. The health of the population is threatened by habitat loss, primarily from sedimentation.

Since its rediscovery, there has been a current Memorandum of Understanding (MOU) recognizing the importance of the robust redhorse and its delicate situation. The MOU includes the GA Department of Natural Resources, NC Wildlife Resources Commission, SC Department of Natural Resources, US Fish and Wildlife Service, US Geological Survey, US Forest Service, Duke Power Company, Georgia Power Company, Georgia Wildlife Federation, South Carolina Aquarium, and South Carolina Electric and Gas Company. The parties agree to be actively committed to the restoration of the species.

The Ogeechee River was chosen as a site to stock because of a lack of invasive predators, some gravel spawning areas, and a lack of major impoundments. From 1997 to 2004, about 43,000 young robust redhorse, were released into the Ogeechee River at three different locations.

Followup research in 2008 and 2011 found that the stocked fish were growing and reaching maturity, but that spawning has only been successful in one location near Louisville. Work still needs to be done to make sure this rare species can thrive in the Ogeechee River and throughout the southeast.

Fauna: Lepomis auritis

Redbreast sunfish by Duane Raver, 1975

Redbreast sunfish
Lepomis auritis

The redbreast sunfish is native to eastern North America and makes its home in freshwater rivers. A relatively small fish, it is considered full grown by the time it is two inches long. The largest one on record measured just 12 inches. They primarily eat immature insects.

Usually olive colored with dark fins, the male’s breast and belly will turn bright orange when spawning. The male makes a nest in sandy material, then guards the eggs and fry after the female lays. Auritis means “big-eared” in Latin and refers to the long tabs that extend behind their eyes.

Redbreast sunfish, caught in Georgia. Shared via Wikimedia Commons.

The redbreast sunfish thrive in waters with flowing current and a stable pH. They like to live in natural structures near riverbanks, like overhanging branches which offer shade and protected habitats. Clearing bank debris, lack of current, or a change in pH levels quickly and dramatically affect the population.

Flathead catfish, an invasive species, is a predator and decimated the redbreast sunfish in other nearby watersheds. Thus far, the Ogeechee and Canoochee Rivers have not been infested with flathead catfish.

Citizens are asked to report sightings of these detrimental catfish to Ogeechee Riverkeeper or the Georgia Environmental Protection Division immediately. Snap a photo and email to info@ogeecheeriverkeeper.org with the approximate location of the sighting.

Flathead Catfish, (Pylodictis olivaris): Mississippi River @ Goose Island across from Northeast Power ramp, Marion County, Missouri.