Charles Lutz, Shirley, Mark G., Johnson, Richard
Ponds with late-planted rice for crawfish will benefit by holding a few inches of water while allowing excess water to drain out. Ponds with plenty of rice straw and or weeds should probably drain off most of the water if you can start flushing the pond next week and continue flushing for the next couple of months. In a few days, water temperatures will again reach the 90s, and decomposition will rapidly deplete the oxygen. Ponds planted with sorghum-sudangrass need to be drained completely as soon as possible to keep the plants from dying.
A few crawfish burrows have opened up since the rain. Some crawfish have actually emerged to look for some water to drop their young while others are staying inside to work the burrows. On average though, the majority of the females have yet to spawn and hatch their eggs. Typically, most of the females spawn in late September through October. Those crawfish will likely remain in the burrows a while longer unless a deep flood covers the burrow.
Low-lying areas that had flood waters back up into the ponds may also develop problems with predaceous fish. Bullhead catfish and green sunfish can eat a tremendous amount of baby crawfish during the fall. If the flood waters recede quick enough over the next few days, it would be good to drain the field to kill these pests.
Pumping capacity is a major factor in deciding when and how much to flood. For the most part, good water quality is easier, faster and cheaper to maintain if a shallow flood is maintained for the first several weeks or until cooler weather prevails. Not flushing a pond when it’s needed will either kill or slow the growth of crawfish.
These are the major concerns to consider when making to decision to hold or let go the “free” water. Each pond is different with respect to vegetation, pumping capacity and population potential. Consider all these factors when deciding when to flood and how often to flush over the coming months. Your decision will ultimately affect the survival and growth of your crawfish crop.
The Louisiana Crawfish Farmers Association has asked us to announce that the association will hold their annual membership meeting and social at the Rayne Civic Center at 6:00 p.m. on October 25, 2007. They will also host the Crawfish Expo in Rayne on November 6, 2007. Contact any LCFA board member about joining or call the association office at (337) 394-8182.
If you have any questions about your particular situation, contact one of the LSU
AgCenter crawfish specialists.
Dr Greg Lutz
State Aquaculture Specialist
SW Regional Aquaculture Specialist
SW Regional Aquaculture Assistant Agent