The rains from Hurricane Isaac look like a free and convenient way for crawfish farmers to flood their ponds, but trying to hold the water through four to six more weeks of hot weather will probably end up killing the crawfish, according to LSU AgCenter aquaculture specialist Greg Lutz.
Farmers should drain the storm water and wait to flood their ponds until late September, Lutz said, although early October would be better.
Isaac’s heavy rains will cause some, but not all, brood females to emerge from their burrows, Lutz said. But it’s too early in the season to keep the ponds flooded just to save the early emerging crawfish.
“The temperature of the water will get too hot, and the rotting vegetation will deplete the dissolved oxygen in the water resulting in extremely high mortality,” Lutz said in the news release.
Unless the ponds are flooded over for several days, only a portion of the brood stock will actually emerge, Lutz said. Most crawfish will remain in the burrows, protected from these lethal conditions.
“The bottom line is that it is better to lose a few early emerging crawfish than to risk losing most of the holdover crawfish and all of their babies,” Lutz said.