Will the Gulf Oil Disaster Result in Redistribution of Species? [w/Video]

“Scientists are concerned that the disruptions to the food chain and redistribution of animals could restructure the ecosystem for years.”

01-12-2011 // Jon Brett

An important question has surfaced following the Gulf oil disaster:

What impact will the toxic combination of oil and dispersant have on the geographic distribution of species in the Gulf of Mexico, and, if there is an impact, what kind of cascading effect will it have on species in the food web ?

The notion stems from the idea that apex animals may be able to sense, and avoid, the deadly toxins. In short, will certain species relocate from traditional areas to find habitable ecosystems, and if they do, how will that impact interconnected species?

“Scientists are concerned that the disruptions to the food chain and redistribution of animals could restructure the ecosystem for years,” said Dr. Doug Inkley , senior scientist at NWF. “The Exxon Valdez oil spill in 1989 had this effect in Prince William Sound where the once-abundant herring population still has not recovered, likely forcing species once dependent on herring to seek other food sources.”

Dr. Aaron Adams, senior scientist at MOTE Marine Laboratory and director of Bonefish and Tarpon Trust (BTT), has worked with recreational and professional fisherman for years on a number of vital fisheries projects.

Over the past few months, Dr. Adams has received a number of reports from tarpon fisherman that challenges traditional migratory models for the majestic and economically potent game fish.

“Anglers and guides have already been telling us about changes in tarpon behavior. For example, instead of moving from East to West, they’re moving from West to East. Instead of going to Louisiana or the Florida panhandle, they might instead go to Mexico, or Honduras, where they get harvested in high numbers.”

Additionally, there is a great deal of concern regarding the Gulf oil disaster’s impact on whale sharks. This concern appears to be valid for a number of reasons.

According to Dr. Erik Hoffmayer, Gulf Coast Research Lab, “the area where the oil spill hit was a prime feeding area for whale sharks and because they’re filter feeders, they spend much of their time at the surface, which is where the oil had accumulated.”

Whale Shark

Taking into account the feeding patterns of the species, the primary concern wasn’t focused on the toxicity of the oil and dispersants, but rather the high level of susceptibility to the physical properties of oil coating their gills.

A big fear was that whale sharks would have their gills covered, suffocate, and sink to the bottom.” said Dr. Hoffmayer.

At the height of the Gulf oil disaster, Dr. Hoffmayer’s team made a startling discovery on a research expedition that would call into question whether or not certain species were able to detect, and avoid, the deadly toxins.

“The hope was that maybe they’d redistribute because of the oil, but the evidence revealed our worst fears: that these animals weren’t detecting oil. In fact, we witnessed three whale sharks swimming directly into the oil,” Hoffmayer said.

While it would appear that whale sharks weren’t able to detect the presence of oil, that doesn’t mean all species were unable to do so. Unfortunately, the state of affairs for the whale shark is very much up in the air for now.

“The three animals that we observed swimming in the oil were never seen sinking, but this probably occurred, and it’s going to take years of population’s data to really get an understanding of what this means,” Hoffmayer said.

In the end, the only thing that’s clear is there are a lot more questions than answers, and it appears as though it will take years, and billions of dollars, before we’ll really know what’s going on in the Gulf. While this may not be the most promising news, it should provide a much needed stimulus to ensure all responsible parties feet are held to the fire, and that proper funding channels are established for the long haul.

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