OCEAN SPRINGS, Mississippi – Another massive fish kill, this time in Louisiana, has alarmed scientists, fishers and environmentalists who believe they are caused by oil and dispersants.

On Aug. 22, St. Bernard Parish authorities reported a huge fish kill at the mouth of the Mississippi River Gulf Outlet.

“By our estimates there were thousands – and I’m talking about 5,000 to 15,000 – dead fish,” St. Bernard Parish President Craig Taffaro told reporters. “Different species were found dead, including crabs, sting rays, eel, drum, speckled trout, red fish, you name it, included in that kill.”

The next day, a thick, orange substance with tar balls and a “strong diesel smell” was discovered around Grassy Island, near the fish kill, according to a news release.

Taffaro admitted that there was oil in the area, but cautioned against assuming it was the cause of the fish kill.

Dr. Ed Cake, a biological oceanographer, as well as a marine and oyster biologist, has “great concern” about this fish kill, and many others in recent weeks, which he feels are likely directly related to the BP oil disaster.

“As a scientist, my belief is that this fish kill is 75 percent likely due to hypoxic conditions, not enough oxygen in the water to sustain life,” Dr. Cake said. “Because it was both bottom dwelling fish and crab, and other fish from the middle of the water column, whatever caused this covered the entire water column. That gives me great concern. The scientist in me says there was some other triggering mechanism.”

Dr. Cake believes the “triggering mechanism” is likely oil and toxic dispersants from the BP oil disaster.

Recent weeks have seen other huge fish kills. One occurred in Mississippi from Long Beach to Pass Christian, and another at Cat Island. The kill earlier this week in East St. Bernard Parish is of note, because taken in the context of the other two, all of these areas share the same body of water – that which comprises both of the Mississippi and Chandeleur Sounds.

On Aug. 18, a team from Georgia Sea Grant and the University of Georgia released a report that estimates that 70 to 79 percent of the oil that gushed from the well “has not been recovered and remains a threat to the ecosystem”.

Nevertheless, regarding the St. Bernard Parish fish kill, the head fisheries biologist for the state of Louisiana, Randy Pausina, blamed it solely on hypoxic conditions caused by extreme heat mixed with nutrient-rich waters.

But Dr. Cake, along with commercial fishermen and Gulf Coast environmentalists, are drawing direct parallels to BP’s oil disaster and the use of toxic dispersants as the likely cause of the increased numbers of fish kills they are witnessing.

“There are several parallels to the spill,” Dr. Cake added. “We have evidence from fisherman operating in the VOO [Vessels of Opportunity] fleet and fishermen in the area who observed the spraying of dispersants by both aircraft and vessels in the immediate vicinity of the fish kills. Therein lies one triggering mechanism.”

He said another factor is that dispersed oil “provides nutrients for phytoplankton, and this may have triggered a bloom of plankton, otherwise known as a red tide, and you would then have a fish kill from the red tide organisms. I understand that the phytoplankton out there is causing fish kills, but still the triggering mechanism is the presence of the oil and dispersants.”

“A fish kill from a red tide, as I’ve observed, causes fish to come to the surface to be in distress, flopping around, and slowly they die, and new ones come up. This was not observed in any of these kills. All we had was a massive amount of dead fish coming to the surface,” he said.

Two commercial fishermen in Mississippi who worked in BP’s VOO programme, James Miller and Mark Stewart, recently told IPS they were eyewitnesses to BP spraying dispersants via airplane and from boats into areas of the Mississippi Sound, as well as outside the barrier islands.

“Right now there’s barely any shrimp out there to catch,” David Wallis, a fisherman from Biloxi, told IPS. “We should be overloaded with shrimp right now. That’s not normal. I won’t eat any seafood that comes out of these waters, because it’s not safe.”

Chasidy Hobbs, with Emerald Coastkeeper in Pensacola, Florida, is on the City of Pensacola Environmental Advisory Board and directs the environmental litigation research firm, Geography and Environment.

Hobbs recently informed IPS of a one mile-long fish kill on Aug. 20 near Pensacola, and said of the BP oil disaster and ongoing use of dispersants, “We’re poisoning the entire Gulf of Mexico food web. It’s criminal.”

“There are two theories on what is causing these fish kills,” Jonathan Henderson, with the Gulf Restoration Network, told IPS. “Hypoxia and the BP disaster. Whichever is the cause, they are both still bad.”

Henderson has logged hundreds of hours in boats and planes across the Gulf documenting the oil disaster. He has seen fish kills himself.

“A few weeks ago at Pass Christian, I saw flounder, trout, and crabs, washed up into the rock barriers in front of the marina,” he said.

The growing dead zone in the Gulf, which scientists believe will be the size of Massachusetts this year, is now already extremely close to shore.

“The fact that the dead zone is this close to shore is alarming to me,” Henderson said, “And we don’t know the effect the dispersants are having on the dead zones and it very well may be that they are making it worse.”

According to the EPA’s latest analysis of dispersant toxicity released in the document ‘Comparative Toxicity of Eight Oil Dispersant Products on Two Gulf of Mexico Aquatic Test Species’, Corexit 9500, along with 9527 – BP’s two dispersants used in the Gulf – “at a concentration of 42 parts per million, killed 50 percent of mysid shrimp tested.” Most of the remaining shrimp died shortly thereafter.

“Local fisherman in Alabama report sighting tremendous numbers of dolphins, sharks, and fish moving in towards shore as the initial waves of oil and dispersant approached in June,” Environmentalist Jerry Cope wrote recently. “Many third- and fourth-generation fishermen declared emphatically that they had never seen or heard of any similar event in the past. Scores of animals were fleeing the leading edge of toxic dispersant mixed with oil. The Gulf of Mexico from the Source into the shore is a giant kill zone.”

“I was amongst all these dead fish in St. Bernard Parish,” Dr. Cake added, “And there were off-bottom fish there as well, which was the same thing we had at the fish kills at Cat Island and Long Beach-Pass Christian, so I see a trend here. Prior to the BP oil spill and the widespread applications of dispersants in all three of these recent fish-kill areas, we have never had evidence of such widespread kills.”