Flathead catfish
Pylodictis olivaris
Also known asYellow cat · Mud cat · Shovelhead cat
Water parameters
Minimum tank: 1500 L per individual at harvest size.
Feed and growth
- Feed protein
- 40% target
- Daily feed (warm)
- 2.00% of body weight
- Daily feed (cool)
- 0.80% of body weight
- Max density
- 30 g per litre
A 8000 g adult eats about 160.0 g of feed per day at optimum. 10 fish at adult size: ~1600 g daily.
Legality
Rules vary by jurisdiction and change over time. Verify with your local fisheries or wildlife authority before stocking.
| Jurisdiction | Status | Notes |
|---|---|---|
| us-general | check local regulations | Native range: legal. Outside native range: several Atlantic-coast states restrict or prohibit live transport to prevent further spread verified 2026-05-14 |
Unlisted jurisdictions default to "check local regulations".
Origin and habitat
Pylodictis olivaris is the second-largest catfish in North America, behind only the blue catfish, reaching about 155 cm and 56 kg; the angling record is a 123-pound fish from Elk City Reservoir, Kansas, in 1998. It is native to a broad area west of the Appalachians, through the Mississippi, Missouri, and Ohio basins and Gulf drainages, north into Canada, west to Texas, and south into northeastern Mexico. Flathead catfish are solitary ambush predators that hold in deep pools, undercut banks, and log jams in big rivers. Unlike the omnivorous, scavenging channel and blue catfish, flatheads are almost purely piscivorous, taking live fish and crayfish, and they resist switching to dead or pelleted food. The flesh is white, firm, and often rated the best of any North American catfish. Stocked outside its range for sport, the flathead has become a damaging invader of several eastern river systems, where its introductions rank among the most ecologically harmful of any North American fish.
Climate and outdoor ponds
- Climate
- temperate (handles seasonal swings)
- USDA zones
- 5–11 (winter low around -29°C or warmer)
- Heating needed
- no
- Cooling needed
- no
Care notes
A difficult species, not recommended for most aquaponics. The sticking point is feeding: flathead catfish are live-prey hunters that strongly prefer to catch and eat live fish, and training them onto pellets is very hard, with most fish refusing dry feed even after long conditioning. Raising them usually means keeping a supply of live feeder fish, which is costly, labor-heavy, and undoes the efficiency of pellet-based aquaponics. On live feed, growth is moderate, around 500–1 g in eighteen to twenty-four months; pellet FCR data are thin because so few fish take pellets. The temperature range is about 10–32°C, best near 24–28°C. Anyone set on trying should start with small fingerlings under 5 cm, which have the best shot at pellet training, since larger fish are nearly hopeless, and keep single-size groups in separate compartments because young flatheads are fiercely cannibalistic. Density must stay low, 5 to 10 g/L, as the fish is solitary and territorial. Fingerlings come from a few southern US hatcheries. The eating quality is exceptional, but the culture difficulty makes this an impractical aquaponics fish.