Gauging health of Louisiana fisheries is a complex task

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.”

But, he added, even those numbers — how much fish, by the pound, gets brought to shore commercially — are disputed, depending on whom you ask and when.

The numbers Gaudé refers to include the landings, value and trip information collected by the National Oceanic and Atmospheric Administration and the state Department of Wildlife and Fisheries.

Comparing the pre-Deepwater Horizon seven-year 2002-09 average of blue crab, brown shrimp, white shrimp and oysters in the Barataria and Pontchartrain basins to the post-disaster, two-year 2010-12 average shows that some fisheries are up while others are down. But that’s only part of the picture.

For a number of species in the basins, the “trip” numbers — showing how many trips fishermen take for a particular fishery — are down, which would in turn could impact how much of the fish is brought to land.

A self-healing problem?

The Lake Pontchartrain Basin Foundation is trying to get a better handle on the status of blue crab in the Lake Pontchartrain area through a three-year study nearing completion from the University of New Orleans.

The blue crab population might be affected by low salinity, by periodic low-oxygen areas in the lake that could be impacting clams and other nonmoving food sources for the crabs, or by a number of other factors, Lopez said.

“There are a lot of bits and pieces of information, but we haven’t pulled it all together yet,” Lopez said. “The problem with any fisheries data it’s just really hard to say.”

There are also considerations of harvest pressure. Maybe more people aren’t going out because fuel prices are too high, or maybe the gear some fishermen are using is having an effect on the numbers, he said.

“Everything has consequence,” Gaudé said.

Chris Macaluso, director of the Center for Marine Fisheries with the Theodore Roosevelt Conservation Partnership and an avid fisherman, said there seems to be some declines in bait fish in some area, while other areas, like Lake Pontchartrain, had declining brown shrimp catches.

“Without a long-term trend, it’s hard to really get a read on what’s causing that,” Macaluso said.

In terms of landings, he said, he hasn’t heard or seen anything that would point to drastic problems at this point, although there have been reductions in catches just west of the Mississippi River from the Empire to Grand Isle area.

“My personal thought on that is it’s a dramatic loss in habitat,” Macaluso said. But this year, people are talking about rebounds in red fish and speckled trout, he said.

“It just points to how dynamic the system is,” Macaluso said.

Another factor is the continuing land loss along coastal Louisiana due in part to erosion and the natural sinking of the land.

“We’ve got multiple problems,” said Pete Gerica, president of Lake Pontchartrain Fisherman Association. The lack of crabs in Lake Pontchartrain is something they’ve been experiencing for two years now, he said.

“Last two seasons, offshore has been dead,” Gerica said. “Last winter was terrible. No one was working out there. I figured we were going to have a real bad season in Lake Pontchartrain.”

That doesn’t necessarily mean it’s a permanent problem.

“In 40 plus years I’ve been fishing, it has a way of taking care of itself,” he said.

In Lake Pontchartrain this year, there have been calm nights, which means warmer water temperatures and the formation of low-oxygen areas. All that can impact the crab fishery.

Meanwhile, the brown shrimp season at Delacroix Island has been great, probably because that area got hit hard during Hurricane Katrina and a lot of the marsh broke up.

“As an estuary erodes, it’s got more nutrients to sustain more life,” Gerica said.

But that productivity starts dropping off after too much marsh is lost and the marsh edge dissolves into open water.

Doubts about diversions

One of the big concerns now for commercial and recreational fishermen in southeast Louisiana is the state’s plans for large diversions of sediment and freshwater from the Mississippi River, said Guidry, of the Louisiana Shrimp Association.

The fishermen have formed a coalition opposing a diversion planned near Myrtle Grove in Plaquemines Parish that would have the capacity of moving 250,000 cubic feet per second.

Small diversions, if operated properly, can help alleviate coastal land loss, he said. It’s the sheer size of the planned Myrtle Grove diversion that has them concerned.

“There’s no way in the world I would trust them (the state) with a 250,000 cfs diversion,” Guidry said.

The state has maintained that with limited funding and large areas of need, reconnecting the river to coastal marshes is a necessary piece in a much larger plan to slow down and eventually stop coastal land loss. The construction is at least a few years away and the state is forming an advisory group to address concerns raised by fishermen and federal agencies.

Deepwater Horizon effect

People who went through the Exxon Valdez spill in Alaska, Gerica said, noted that oil spill impacts on fisheries should start showing up in about three years.

He said the state Department of Wildlife and Fisheries “is like mum is the word” when it comes to possible problems and solutions. “Without the BP money, wildlife and fisheries would be bankrupt. They’re not going to be too quick to admit there are problems out there.”

“I don’t think we’re going to know the full effect of the oil spill until many years from now,” said Guidry, of the Louisiana Shrimp Association.

The Deepwater Horizon impacts to natural resources in Louisiana are being documented through the Natural Resource Damage Assessment under the Oil Pollution Act of 1990. It is a legal process and information gathered for that process may not be available for years, some state officials say.

“We do continue to monitor landings data to get a sense of fisheries trends,” Randy Pausina, Department of Wildlife and Fisheries assistant secretary, wrote in an email. “While landings data can be useful management tool, that data does not provide a complete picture regarding the state of a fishery in a region like the Gulf or in the State of Louisiana, particularly in light of the Deepwater Horizon oil spill.”

Wildlife and Fisheries would not make any of its biologists available for an interview without receiving written questions in advance. However, the agency did release general statements in lieu of an interview.

“As with all landings information, there is variation in the data due to a number of causes, so landings alone should not be used to gauge the health of the resource,” Pausina wrote. “With that caveat, landings of all the major commercial species in Louisiana are dramatically reduced when prespill numbers are compared to post-spill landings data.”

Within the Pontchartrain and Barataria basins, he wrote, there were 30 percent to 38 percent reductions in blue crab in Barataria and brown shrimp in Barataria and Pontchartrain. There was a 68 percent reduction in oysters in Pontchartrain basin, he wrote.

‘We do have hope’

Gerica, of the Lake Pontchartrain Fisherman Association, is optimistic about the future of the fisheries industry.

“I really think nature is going to take care of itself,” Gerica said.

He said he’s seen hard freezes in the past that almost wiped out a species, but it came back.

With a little help, like some of the coastal restoration work underway by the state or rebuilding oyster reefs, the system should recover.

Another factor to consider: There are far fewer fishermen working along the coast than there were 10 years ago. Gerica said it’s normal for the fishing industry to go through major purges every five to six years, when people get out of the business for awhile and then return as fishing picks up.

Part of that can been seen in the number of trips fishermen are taking, although some of that also can be attributed to fuel costs.

“We’re lean and mean right now,” said Guidry.

Although there are fewer fishermen, the amount of seafood harvested has not changed dramatically.

“If you look at production levels, it’s pretty constant except for 2010,” Guidry said.

He also recognizes the troubles the shrimp industry has experienced the past 10 years: imported shrimp lowering prices, fuel prices increasing, multiple hurricanes and then the oil disaster.

“All in all it’s been rough since 2001,” Guidry said. “But we do have hope.”

Diseases and other problems with imported shrimp production have caused prices for domestic shrimp to increase, he said, and that could continue.

In addition, efforts from the Louisiana Seafood Promotion and Marketing Board and others have helped create a demand for Louisiana-caught seafood.

“If left to our own ingenuity, I think we can grow and prosper,” Guidry said. “I feel better this year than I’ve felt in the past 10.”