Fish Kills and Dead Zones Create Confusion in the Gulf
Friday 24 September 2010
by: Mike Ludwig, t r u t h o u t | Report
In Grand Isle, Louisiana, the carcass of a fish leaks oil when poked. (Photo: Jeff Warren / Flickr)
Earlier this week, thousands of fish died and floated to the surface of Bayou Robinson in the Plaquemines Parish area of southern Louisiana. The massive die-off was the third found near the parish in a week, prompting outrage from local leaders who want to know if leftover oil and toxic dispersants from the massive BP oil spill are to blame.
"We've never seen so many species floating in so many different areas," Plaquemines Parish President Billy Nungesser told local reporters.
The fish kills occurred in areas contaminated by oil from the BP spill, and tar balls and oil sightings have been reported nearby as recently as September 16.
State officials responding to the fish kills, however, could not initially put the blame on BP.
Randy Pausina, assistant secretary of Louisiana Department of Wildlife and Fisheries (LDWF) told Truthout that his department acts as a "first responder" to fish kills, and its initial assessment concluded that the fish near Plaquemines Parish died from depleted oxygen levels.
Depleted oxygen levels, also known as "hypoxia," are common in the northern Gulf of Mexico in the late summer months and cause fish kills on an annual basis, but the LDWF's initial assessment was quickly scrutinized by local politicians and media.
"I hope the state wildlife is right, I hope the dead fish is just oxygen," said Nungesser. "I got 100 fishermen here say no way Jose, they been here their whole life and never seen so many species [of fish] in so many different areas, and is it a coincidence that all of those areas happen to have heavy oil."
Pausina explained that the fish were trapped in shallow water during a low tide. Oxygen-consuming algae and bacteria thrive in warm, shallow water, contributing the annual fish kills of late summer. The LDWF is waiting to collect fresher fish kill samples and receive laboratory results, and officials could not make a direct correlation to the BP spill, Pausina said.
Martin T. O'Connell, director of Nekton Research Laboratory at the University of New Orleans, told Truthout that he trusts the LDWF to do a thorough job examining the fish kills.
"... if I had to guess whether these fish kills are 'natural' or a result of direct toxicity from [oil], I would bet these are natural kills," O'Connell said. "We've had a very hot summer and the last few weeks have been especially dry and calm, with few fronts moving though to stir up the water and add oxygen."
"Now it is possible that we're seeing more kills because more fishes moved inshore this summer to avoid the oil-impacted area and now they are being exposed to more hypoxic and anoxic habitats, but it would be very hard to test that," O'Connell said.
The LDWF is not shying away from testing as the state scrambles to document the damages wreaked on its communities and ecosystems by the BP spill.
Last week, LDWF Secretary Robert Barham sent a letter to BP once again urging the company to fund a $173 million, multi-year, testing program to assure the public of the safety of Louisiana seafood. BP has refused two proposals to pay for testing programs in the past, even though the company spent more than $100 million on "advertising, image promotion and damage control" for its own benefit, as Barham points out.
"BP representatives made it clear that, in their opinion, there is no negative public perception of Louisiana seafood as a result of the oil spill ... That 'opinion' of BP's is fundamentally disconnected from reality," Barham wrote in his September 15 letter to BP. "The Louisiana Department of Culture, Recreation and Tourism reports that approximately 50 percent of those surveyed nationwide believe that Louisiana restaurants may be putting their customers at risk due to contaminated product."
While Louisiana fisherman are left to wonder if this crisis of consumer confidence will do further damage to their industry, they are ready to blame BP for the severity of this year's fish kills, according to Rocky Kistner, a journalist and blogger with the Natural Resource Defense Council.
Kistner writes that a "crisis of communication" about the effects of the oil spill is not making the recovery effort any easier on local fisherman and their communities.
"I have talked to countless people here complaining about poor information from EPA scientists and fish and wildlife experts," Kistner writes. "I watched people here in Plaquemines Parish roll their eyes in disbelief as federal and state health officials tell them there are no contaminated fish here. How can you say nothing is contaminated when this much oil is in the water, they ask?"
Whether or not oil from the spill is killing more fish, the hypoxic "dead zone" in the northern Gulf does not help, according to Pausina.
The northern Gulf of Mexico has the largest hypoxic area of any coastal water of the United States and the second-largest in the world, according to a report released earlier this month by the National Oceanic and Atmospheric Administration (NOAA).
The Gulf dead zone is largely caused by fertilizer and organic compounds in agricultural runoff carried down the Mississippi and other rivers. These nutrient-rich runoffs support oxygen-depleting plumes of algae and bacteria in warm summer waters.
Scientists have known about the problem for years, and the report shows that the percentage of hypoxic dead zones in US coastal areas has increased dramatically since the 1960s.
The NOAA announced with the report that oxygen levels in the deep waters within 60 miles of BP's leaking wellhead dropped 20 percent following the oil spill as microorganisms consumed the carbons in the water column.
While significant, the 20 percent decrease is not enough to create dead zones in deep ocean water, according to the NOAA. The oxygen levels have stabilized and dead zones are not expected in the future.
The release does not include any information on how oil in shallow water may have made the pre-existing dead zones worse, and the report "does not discuss the broad ecosystem consequences of hydrocarbons released into the environment," according to the NOAA.
This statement exemplifies the crisis of communication in the Gulf, where conflicting data propelled by conflicting interests continues to confuse and frustrate an exhausted public.
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