Oceana Magazine Summer 2014: Tuna in Trouble
Tuna in Trouble
Picture an ocean super-predator. It’s one of the largest and fastest fish in the entire ocean — growing up to 8.5 feet long and nearly 900 pounds, but still capable of charging through the water at more than 45 miles per hour in short bursts. This fish has glistening, silver-blue scales, sickle-like fins, a row of wicked-looking yellow spines along its back, and rows of sharp teeth. But this beautiful and formidable predator is not a shark — it’s a tuna.
The Atlantic bluefin tuna is deceptively fearsome — most culinary fans of tuna don’t realize that the fish on their plate, Thunnus thynnus, is a highly evolved ocean predator. But unfortunately for bluefin tuna, their size and muscle power make them a highly valuable commercial species. During the past three decades, the Atlantic bluefins population fell dramatically due to overfishing, but Oceana and our allies were successful in halting the decline. Now, just as the tuna are starting to recover, oil and gas exploration in the Mediterranean could jeopardize their recovery.
“If we allow oil and gas exploration in the Spanish Mediterranean, it could undo all of our hard work to help this species recover,” says Xavier Pastor, Oceana senior vice president and executive director for Europe.
Atlantic bluefin tuna are loosely divided into eastern and western populations: the two stocks mingle in the open ocean, but they return to opposite ends of the compass to breed. Eastern bluefins breed in the Mediterranean Sea, while the westerns breed in the Gulf of Mexico.
Both populations collapsed by the early 1980s, after an explosion in the industrial fishing fleet and better gear allowed fishermen to travel farther into the ocean in search of tuna. In 1998 the International Commission for the Conservation of Atlantic Tunas (ICCAT) set quotas to attempt to halt the decline, but the numbers were still far higher than scientists advised. Scientists estimate that between 2005 and 2011, the actual bluefin tuna catch exceeded the total allowable quota by 44 percent, according to a 2013 study in PLOS ONE.
Then in October of 2012, an ICCAT assessment revealed the first signs of recovery for both eastern and western bluefin. The commercial fishing industry clamored to raise the quotas, says Pastor, but Oceana and our allies insisted that doing so would completely undermine further recovery. Since then, Oceana has campaigned to keep bluefin tuna quotas steady in the face of constant pressure from the fishing industry. Yet overfishing isn’t the only thing threatening eastern bluefins.
Spain’s Balearic Islands are known for their tourist-filled beaches and blue waters, but they are also the most critical breeding ground for eastern bluefin. Each summer, tens of thousands of tuna migrate to the area’s warm waters to spawn. Yet these breeding grounds could soon be inundated with the deafening blasts of seismic airguns.
The Spanish government is planning to open 45 percent of the Spanish Mediterranean to offshore oil development, putting the Balearic ecosystem at risk and jeopardizing the bluefin tuna’s recovery. Two energy companies, Spectrum and Cairn, want to use seismic airguns to map 11.3 million marine hectares of ocean in Andalusia’s Alboran Sea, Catalonia, Valencia, and the Balearic Islands.
Seismic airguns shoot deafening blasts of compressed air through the water, and the resulting sound waves create a map of oil and gas deposits deep beneath the ocean floor. The resulting underwater noise is immensely harmful to marine life. Pastor says that airguns can kill fish eggs and larvae, as well as disrupt fish hearing capacity, schooling structure, swimming behavior, and possibly migration.
Oceana estimates that the noise will actually extend far beyond the 11.3-million-hectare survey area, says Pastor, disturbing more than 17 million marine hectares of ocean, including 82 protected areas. Under the current plans, seismic blasting would occur a mere 40 kilometers away from the Balearic Islands and the tuna’s spawning grounds.
“Energy exploration will undoubtedly hinder this fishery’s recovery,” says Pastor.
Seismic airguns will harm both the tuna, and the very fishermen that depend upon them and other commercial fish species in the Mediterranean. After seismic surveys in the North Atlantic, fishermen’s catches of cod and haddock declined by 40 to 80 for at least five days over thousands of square miles, according to a 1996 study in the Canadian Journal of Fisheries and Aquatic Science. And some of these potential drilling projects are located near the boundary of Spain’s Exclusive Economic Zone, where a future spill could seep into the waters of other countries.
“We must not forget that this work will simply be a precursor to other work with a more serious environmental impact, such as drilling and the transportation of crude oil,” said Ricardo Aguilar, director of research of Oceana in Europe, in a press release. “It is only a question of time before there are accidents and spills.” Oceana raised the alarm about the dangers of offshore drilling more than five years ago. Since then, Pastor and his team have worked with the Balearic Islands and regional governments to oppose seismic surveys, and urged the Spanish government to halt offshore drilling.
“We are mobilizing everyone — actors, politicians, local authorities, businesses, nonprofits, and citizens — in order to voice our opposition to seismic testing to the national authorities,” says Pastor. “We have also developed scientific papers to publicize the ecological impacts of seismic testing, particularly stressing the damages to iconic protected species,” he says “as well as the indirect socioeconomic consequences for fisheries and tourism.”
Recently, more than 50 organizations from the Balearic Islands, including town halls, governments, and tourism groups formed a lobbying group to fight back, called the Mar Blava Alliance. Their petition against exploration and drilling have already exceeded 40,000 signatures. Meanwhile, residents of Ibiza and other Balearic islands have gathered in crowds of nearly 20,000 to protest the government’s plans.
Pastor says that progress is being made on a new technology, called marine vibreoseis, which create sounds through vibrations, reducing harm to marine mammals and fish. “Such alternative should be encouraged and required by strong policy developments,” he says.
Oceana is also pushing increased bluefin protections outside of the Balearic Islands, by advocating for the continued use of science-based fishing quotas to ensure that overfishing does not occur.
“The bluefin tuna fishery is a very important and historic fishery,” says Pastor, “and we are going to make sure that the population is allowed to rebuild and recover.”