Georgia Wildlife Resources Division
2067 U.S. Hwy. 278, SE, Social Circle, GA 30025
As one of the largest freshwater catfish found in Georgia, flatheads can reach weights exceeding 120 lb, though most captured are found at smaller sizes (less than 50 pounds).
Often referred to as “mudcats,” “Appaloosa catfish,” or “shovelhead catfish,” they are easily distinguished by their flattened head and free, flap-like adipose fin. The species has yellowish pigmented skin mottled with brown and green; a lower jaw that extends beyond the upper jaw; small eyes; and a non-forked tail. Flatheads may be found throughout various habitats within the river, though they typically prefer deeper waters (e.g. bends in the river) (TPWD 2016).
An apex predator, the diet of flatheads varies and evolves as they mature. Young invertebrates (crayfish, insects, etc.) typically are their primary diet item of flatheads (<300 mm), with fish becoming more prevalent as they grow. Large flatheads (>500 mm) are almost exclusively piscivorous, hence the common use of live bait by fishermen targeting the species. In Georgia, direct predation by larger flatheads has been observed on multiple species of ictalurids (catfish), including various bullhead catfish (Ameirurus spp.), channel catfish (Ictaluris punctatus), white catfish (Ameiurus catus), and even other flatheads (Weller and Robbins 2001). Additionally, they have been noted to prey heavily on several species of centrarchids (panfish), including bluegill (Lepomis macrochirus), largemouth bass (Micropterus salmoides), redar (Lepomis microlophus), spotted sunfish (Lepomis punctatus), and most notably, redbreast. On June 9, 2010, a partially digested (but well intact) juvenile Atlantic sturgeon was recovered from the stomach of a flathead catfish from the Satilla, and while this is the first confirmed field observation of flathead catfish predation on any sturgeon species, it further solidifies the notion that flatheads may consume virtually any available fish prey (Flowers et al. 2011).
The life span of flathead catfish may exceed 30 years, though most do not live that long (Marshall et al. 2009). In Georgia, the spawning season for flatheads occurs from spring through summer. Nesting often takes place in hollow logs, caves, or areas beneath the banks, where the female deposits thousands of eggs and males guard them. Though the number of eggs deposited by a female varies greatly depending on her size, females may lay up to 100,000 eggs at a time (TPWD 2016). After a 4-6 day incubation period, the fry (very young fish) will school together at the nest for several days before eventually seeking independent shelter beneath rocks, roots, and other cover (TPWD 2016). Interestingly, in the Satilla, staff with the Georgia Department of Natural Resources (GA DNR) have noted multiple instances of female catfish responding to high exploitation rates by maturing at smaller sizes and younger ages (Bonvechio et al. 2011). Such a compensatory mechanism has been noted in some marine species, and it’s observance in Satilla flatheads is likely reflective of the population impacts associated with ongoing reduction and removal efforts by GA DNR staff.