July 29, 2013
A few months ago, John Lopez was looking for blue crabs for a boil he was planning at the New Canal Lighthouse in New Orleans, but the pickings were scarce.
When he finally found some, he cleared out the last the store had and then bought some crawfish to make up the difference.
It was an indication of what he’d been hearing. The number of crabs being caught in Lake Pontchartrain seemed to be down this year, said Lopez, executive director of the Lake Pontchartrain Basin Foundation.
It’s unclear whether the 2010 BP/Deepwater Horizon oil disaster has had any effect on Gulf fisheries. Commercial harvest records in the Barataria and Pontchartrain basins show no clear effects yet, but most scientists and fishermen warn that making any conclusions about ecosystem health based on these records is problematic at best and misleading at worst.
Lopez notes the scarcity of blue crabs could be due to the high levels of freshwater in Lake Pontchartrain and Lake Borgne the last three or four months, probably from higher-than-normal river flows from the Pearl River. But he doesn’t rule out possible long-term impacts from the Deepwater Horizon disaster.
There are many variables, beyond the Deepwater Horizon, that play a part in the health of fisheries: a series of tropical storms, fishery population variations, opening of freshwater diversions to combat the oil leak, high water levels, cooler than normal spring, and both higher-than-normal and lower-than-normal salinities, just to cite a few.
“It’s so nebulous,” said Rusty Gaudé, Louisiana Sea Grant marine extension agent for Jefferson, Orleans, St. Charles and St. John parishes. “The only thing you can say definitively is the numbers.”