International Dredging Review

International Dredging Review

Dredging schedules along the coasts have been dictated by the sea turtle nesting season and migration patterns for decades so it was discouraging to learn that all species of sea turtles in the Gulf of Mexico are at risk and are dying as a result of the Gulf of Mexico oil spill.

I called Dena Dickerson turtle expert at ERDC to ask her about a report by the operator of a vessel of opportunity working with a turtle rescue operation who said that BP was not allowing the rescuers to remove turtles from entrained oil before they burned it. Dickerson was not able to speak to that report but told me that her group was preparing to go into the Gulf and trawl for older turtles that are below the surface. She said on June 23 that the vessels were identified and ready to go but that they were getting a lot of “pushback” from BP on the project which will be an attempt to evaluate the oil impact on the turtles.

On July 6 she reported “I am just back from Grande Isle doing some recon work for the trawling study. As far as I have been told it is still moving forward but it has not been approved yet. We only saw a few tar balls and no oiled water where we were in Grande Isle.”

On June 23 I also called Blair Witherington a recognized expert on sea turtles who works for the Florida Wildlife and Conservation Commission and had been in a boat 20 to 80 miles offshore for a month – rescuing juvenile turtles from their habitat in sargassum a floating alga that collects in convergence zones in the ocean and which forms a habitat for small turtles – including Kemps Ridley Green Loggerheads and Hawksbills.

“The sea tends to organize things” he said and all floating things are eventually collected in long lines.
Unfortunately said Witherington the oil collects in convergence zones also and when booms are towed between two vessels to collect oil for it is likely to contain sargassum with its wealth of marine life including turtles. Asked about the reports of BP burning entrained oil without removing the turtles he said that before the reports communication was difficult but that after the reports “things have eased up” and communication had improved.

“Everyone has an interest in doing the job and not harming the turtles” he said. “This is a classic tragedy – a tragic set of circumstances in which there are no villains.”

All at-risk sea animals from the Gulf of Mexico go to the Audubon Aquatic Center in Algiers across the Mississippi from New Orleans and the 64 turtles Witherington collected in his first voyage were transported there. Meaghan Calhoun of the Aquatic Center said in late June that of the 109 oiled turtles they had received so far 106 had survived.
The three that died she said had ingested enough oil that all their internal organs were coated with it. Others that ingested smaller amounts of oil were able to pass it and return to health. The crew at the Audubon Center washes the
turtles then places them in individual tanks where they are observed and tested. They will all be held until the oil crisis in the Gulf is over and will then be released back into the wild.

Judith Powers