September 22, 2017 — Even in trace amounts, oil can warp the spines, disfigure the faces and weaken the hearts of redfish larvae. That makes it difficult for young fish to swim, eat and grow into the 40-pounders that excite anglers.
The first comprehensive study of oil spill effects on the popular sport fish found that “micro-droplets” of oil, such as those that disperse after larger spills, cause skull and jaw deformities and can twist backbones upward, producing fish with awkward J-shaped bodies. Exposure to small amounts of oil reduced the cardiac functions of redfish by 70 percent, according to the study published this month in the journal Science of the Total Environment.
“Certainly, oil spills kill,” said Alexis Khursigara, a marine scientist with the University of Texas and the study’s lead author. “But sometimes those that survive can have complex deformities that can result in a delayed death because they’re not swimming well or fast enough, or they have a hard time capturing prey.”
More than 1 million of the fish, known as red drum, were caught in Louisiana waters last year, making it the second largest recreational catch after spotted seatrout, commonly called speckled trout. Commercial fishing for redfish was banned in Louisiana in the late 1980s to keep the species from becoming extinct, amid the Cajun food craze that was popularized nationally by legendary New Orleans chef Paul Prudhomme’s blackened redfish dish. By 1988, only 2 percent of the fish were escaping capture to spawn offshore.