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October 2011 Issue

Protected Mexican Marine Park Experiences Major Recovery
A protected undersea wildlife park near the southern tip of Mexico's Baja peninsula saw a 460 percent increase in biomass over a 10-year period, showing that depleted sites can recover up to a level comparable to remote sites that have never been fished by humans, said a study led by Scripps Institution of Oceanography researchers.

The analysis of the 71-square-kilometer Cabo Pulmo National Park, published in PLoS ONE in August, was conducted from 1999 to 2009. Citizens living around Cabo Pulmo, Mexico, established the park in 1995 and strictly enforced its "no take" restrictions after their waters had been depleted by fishing.

The authors note that factors such as the protection of spawning areas for large predators have been key to the reserve's robustness. Local enforcement has also been a major factor in the park's success.

"The study's results are surprising in several ways," said Octavio Aburto-Oropeza, a Scripps postdoctoral researcher and lead author of the study. "A biomass increase of 463 percent in a reserve as large as Cabo Pulmo represents tons of new fish produced every year. No other marine reserve in the world has shown such a fish recovery."

Strictly enforced marine reserves have been proven to help reduce local poverty and increase economic benefits, the researchers said. Cabo Pulmo's marine life recovery has spawned eco-tourism businesses, including coral reef diving and kayaking, making it a model for areas depleted by fishing in the Gulf of California and elsewhere. For more information, visit http://scrippsnews.ucsd.edu.

Scientists Find Most Deep-Sea Fisheries Are Unsustainable
A team of marine scientists have recommended an end to most commercial fishing in the deep sea, suggesting instead that fishing should be carried in more productive waters nearer to consumers.

The study was published online in Marine Policy, just before the United Nation's mid-September meeting to decide whether to continue allowing deep-sea fishing in international waters.

Funded by the Lenfest Ocean Program, the team's report states that with some rare exceptions, deep-sea fisheries are unsustainable.

"The deep sea is the world's worst place to catch fish," says marine ecologist Elliott Norse, the study's lead author and president of the Marine Conservation Institute. "Deep-sea fishes are especially vulnerable because they can't repopulate quickly after being overfished."

The deep sea provides less than 1 percent of the world's seafood. Since the 1970s, when coastal fisheries were overexploited, commercial fishing fleets have moved further offshore. Some now fish more than a mile deep.

"Deep-sea fisheries can be sustainable only where the fish population grows quickly and fisheries are small-scale and use gear that don't destroy fish habitat," Norse said. "Killing off life in the deep sea one place after another isn't good for our oceans or economies."

The authors suggested redirecting subsidies from high-seas trawlers to displaced fishermen. According to the study, high-seas trawlers receive $162 million each year in government handouts, amounting to a quarter of the value of the fleet's catch. For more information, visit www.sciencedaily.com.

Shrimp Species, Tubeworms Seen Together at Hydrothermal Vent
Ocean scientists on the NOAA Ship Okeanos Explorer in August observed two species thought to have never before been seen together at a hydrothermal vent—chemosynthetic shrimp and tubeworms. They also observed the first known live tubeworms ever seen at a hydrothermal vent in Atlantic waters.

The discoveries were made during an expedition to the Mid-Cayman Rise, an ultraslow spreading ridge south of Grand Cayman Island in the Caribbean. The crew's findings could provide clues to questions about biodiversity and the global distribution of vent organisms and the origins of life.

"To find both [shrimp and tubeworms] together has important implications for the evolution of vent communities in the Caribbean as the Atlantic became separated from the Pacific some five million years ago," said Paul Tyler, a marine biologist from the University of Southampton.

A number of technicians aboard the ship operated an ROV at depths of up to 3,500 meters below the surface. Using a new model of telepresence-enabled ocean exploration, the Okeanos Explorer team conferred with onshore scientists at a network of Exploration Command Centers, connected to the ship's sensors, systems and people in near-real time by satellite and high-speed Internet.

While chemosynthetic animals live at vent sites around the globe, over the past three decades scientists have learned that distinct species of animals inhabit vent sites in different oceans. They have theorized that different geologic and oceanographic features may control biodiversity at these sites.

Vent sites in the Atlantic are dominated by shrimp; those in the Pacific by giant tubeworms. Smaller tubeworms have been found at seafloor cold seeps in the Gulf of Mexico and off the West Coast of Africa, but until this discovery, no tubeworms had been observed at hydrothermal vents in the Atlantic. For more information, visit http://www.noaanews.noaa.gov.

Most Ocean Species Have Yet to be Discovered, Study Finds
A new calculation from the Census of Marine Life estimates that Earth contains a total of 8.7 million species, 2.2 million of which are ocean-dwelling. Of marine species, however, 91 percent have yet to be discovered, described or catalogued, the study found.

This calculation, announced in August, is the most precise ever, researchers said. Previous estimates ranged between 3 million to 100 million species on Earth.

Researchers refined the estimated species total by identifying numerical patterns within the taxonomic classification system. By analyzing the taxonomic clustering of the 1.2 million species today in the Catalogue of Life and the World Register of Marine Species, they discovered numerical relationships between the more complete higher taxonomic levels and the species level. New techniques such as DNA barcoding are radically reducing the cost and time involved in new species identification. For more information, visit www.coml.org.


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