Appearance:
Elongated, gray, and scaleless catfish-type body with a large mouth, sharp pectoral spines, and four pairs of barbels; light to dark gray in color, but albinos occur; noted for the ability to breathe air and make short overland movements by pulling themselves along with their pectoral fins much like an infantry-man scooting under the barbed wire; early accounts that this fish would eliminate native fishes were erroneous, and it has not had significant detrimental effects; species occasionally abundant and still considered undesirable.
Range:
Most commonly encountered in the Everglades and associated canals, but also occurs throughout central and southern Florida. First reported in 1967 in Broward County and later in Hillsborough County, these two populations have now merged. Abundance has decreased since 1970, with a native range in Southeast Asia.
Habitat:
Prefers shallow and highly vegetated water bodies; sometimes abundant in small, deeper ponds without the usual complement of native fishes. They sometimes dominate small Everglades pools during the dry season, but not necessarily to the exclusion of native fishes. They are much less abundant in large lakes and canals, and then usually only found in shallow vegetated areas; can live and even thrive in water with little to no oxygen since can breathe air; well-adapted to transient water bodies with muddy bottoms that partially dry up seasonally; occasionally found in road storm drainage systems from which they emerge during flooding events; habitat preferences tend to segregate this fish thereby reducing its overall effect on native species.
Behavior:
Spawning Habitats: Little known, but reports from India indicate spawn early in the rainy season when they build nests in submerged vegetation; adhesive eggs are laid on vegetation, and guarded by the male.
Feeding Habits: Opportunistic, consuming a wide variety of food items, including small fish, aquatic insects, plant material, and detritus; also scavenges on dead fish, etc.
Age and Growth:
Fairly rapid, with sizes up to about 12 inches; the maximum size is about 20 inches and three pounds.
Sporting Quality:
None
Edibility
Not commonly eaten in western societies, but prized in native range (possibly in part because they can be kept alive in moist bags for transport); no bag or size limits.
State Record:
N/A
Fishing Tips and Facts:
Special Note: Possession and transportation of live walking catfish is illegal without special state and federal permits;they can only be possessed dead, so anglers who want to try eating them should immediately put them on ice.
Additional Information:
Within Asia, this species has been introduced widely. In the United States, it is established in Florida and reported in California, Connecticut, Georgia, Massachusetts, and Nevada, and is regarded as an invasive species.
The walking catfish was reportedly imported to Florida from Thailand in the early 1960s for the aquarium trade. The first introductions apparently occurred in the mid-1960s when adult fish imported as brood stock escaped, either from a fish farm in northeastern Broward County or from a truck transporting brood fish between Dade and Broward Counties. Additional introductions in Florida, supposedly purposeful releases, were made by fish farmers in the Tampa Bay area, Hillsborough County in late 1967 or early 1968, after the state banned the importation and possession of walking catfish. Aquarium releases are likely responsible for introductions in other states. Dill and Cordone (1997) reported that this species has been sold by tropical fish dealers in California for some time. They have also been spotted occasionally in the Midwest.
In Florida, walking catfish are known to have invaded aquaculture farms, entering ponds where these predators prey on fish stocks. In response, fish farmers have had to erect fences to protect ponds. Authorities have also created laws that ban possession of walking catfish.
