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Help for Kelp—Seaweed Slashers See Harvesting Cuts Coming

A new global certification program aims to protect from overfishing wild seaweeds, which serve not only as a crop but a habitat for hundreds of other ocean species
seaweeds


Seaweeds are a harvestable marine resource, and therefore a fishery, but they also serve as habitat for other sea life.


Credit: Arneoste via Wikimedia Commons

Think of overfishing and sea creatures like majestic bluefin tuna, steely sharks or New England’s treasured cod come to mind. For most of us, seaweed isn’t part of the overfishing conversation. But the Marine Stewardship Council, best known for its ecolabeling and certification program for wild seafood, says seaweeds are an important component of the marine ecosystem that deserve more attention and protection. Last month the MSC announced its plan to develop the first global standard for sustainable seaweed. The organization hopes to begin certifying seaweed fisheries by the end of 2014.

We use seaweeds to wrap sushi and to thicken ice cream and yogurt. They’re also found in products ranging from cosmetics and pharmaceuticals to fertilizers and animal feed. What makes seaweed unique is its dual function. Seaweeds are a harvestable marine resource, and therefore a fishery, but they also serve as habitat for other sea life.

More than 95 percent of global seaweed production (which totals approximately 21 million metric tons a year) is farmed. China, Indonesia and the Philippines lead global production. Only a small fraction of the total seaweed harvest is cut from the wild, according to the most recent fisheries data gathered by the United Nations Food and Agriculture Organization.

Yet concerns over wild seaweed harvest have been building. In late April the Philippines Department of Agriculture imposed a ban on the collection, sale and export of brown seaweed and sea grass. High demand for the sea vegetable brought uncontrolled harvesting and with it worries over lost habitat for diverse marine life, including juvenile fish and crustaceans that depend on the wild plants for shelter and food.

In British Columbia a 2012 pilot project that allowed licensed harvesters to collect wild seaweed from beaches became controversial after researchers published a study warning the practice “causes direct and indirect harm to fish, fish habitat, commercial fisheries and ecosystems.”

Perhaps no place better than Maine can illustrate why a certification program, like the one MSC is proposing, could be valuable. The state has never had a management plan in place for its $20-million rockweed (a brown algae or seaweed) industry. For most of the 1990s harvesters brought in just over 450 metric tons of seaweed a year. By 2013, seaweed landings exceeded 7,700 metric tons, much of it destined to become fertilizer or livestock feed. Whereas that haul represents only 1 percent of the state’s total rockweed biomass, some scientists, including Robin Hadlock Seeley, a senior research associate at Cornell University Shoals Marine Laboratory in Maine, are worried an expansion of Maine’s harvest areas may have unintended long-term impacts. “Rockweeds are long-lived and habitat forming,” Seeley says. “These plants persist for centuries. They’re the underwater old-growth forest.” And she adds that officials cannot apply typical fisheries management techniques to wild seaweed fisheries and expect the same outcome. “When you think about managing fisheries, you’re thinking about maximum sustainable yields,” she notes. But this equation ignores all the other sea life that depends on the rockweed for food and shelter. “Rockweed is the habitat, and it’s used by 150 other species,” she says.

To address the problem Maine put together a team of scientists, environmentalists and business representatives and asked them to develop a fishery management plan for rockweed. Linda Mercer, director of the Bureau of Marine Science for the Maine Department of Marine Resources, says with the development of the new fishery management plan the state is a step ahead of any overharvesting problems. “We didn’t develop the plan because there’s a threat to the resource,” she says. And implementation of the plan recommendations will have to wait until at least January 2015, when the state’s legislature returns to session.

By then, the MSC hopes to begin certifying seaweed fisheries all over the world. Yet many environmentalists worry that the standards the MSC comes up with will not be strict enough. Part of the concern is that scientists have not established how much seaweed can be safely harvested. “Sustainability depends on the area and how much is being taken—but right now, we don’t know where that is,” Seeley says. “We need to find out the long-term impacts.”

In addition, many environmental advocates say the MSC’s standards for other fisheries have grown weak over the years, and that the organization is certifying fisheries that are not truly sustainable. “Even the fishing community is saying the [MSC] process has been watered down,” Seeley notes.

The MSC rejects this charge and says their seaweed standards will be based on the biology of the species and the scale and intensity of the fishery. “The MSC standard has not been watered down and does not and cannot set arbitrary standards,” says David Stone, MSC spokesman. “The MSC entirely agrees with the statement that sustainability depends on the areas and how much is being taken; this is fundamental to our certification process.” Scientists and environmentalists will be watching the MSC standards to see.

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