Japanese Researchers Turn to Vegetables to Save Seaweed from Hungry Sea Urchins

Researchers in Japan are feeding vegetables to sea urchins to prevent them from consuming dwindling seaweed stocks. The coastline faces significant seaweed loss due to overgrazing sea urchins and environmental factors. Innovative methods could render these urchins more commercially valuable and help preserve vital seaweed forests.

In Japan, researchers are endeavoring to protect dwindling seaweed stocks from ravenous sea urchins by feeding them vegetables—a staple ingredient in sushi.

The country currently faces a 'desertification of the sea,' a phenomenon where coastlines lose significant seaweed forests vital for marine life and local fishing economies. In Sagami Bay, Kanagawa, seaweed beds have shrunk by 80% over the past three decades, according to researcher Yutaka Harada from the Kanagawa Prefectural Fisheries Technology Center.

Contributing factors include overgrazing by sea urchins and rising sea temperatures. However, controlling the population of these herbivores presents challenges. 'There are abundant sea urchins in areas where seagrasses have vanished,' stated researcher Shozo Takamura. 'Divers and fishermen attempt population control, but their numbers remain high.'

Unlike marketable sea urchins, most from coastal Kanagawa have limited edible parts, making them less commercially appealing. Researchers are now exploring ways to cultivate these urchins to increase their economic value.

'Pacific purple sea urchins raised on vegetables like surplus cabbages and Japanese mustard spinach show higher edible parts,' Harada explained. This approach boosts their edibility from a mere 2-3% to as much as 20%, with a less bitter taste.

This initiative could enhance the commercial value of local urchins, creating a stronger economic incentive for fishermen to catch them and ultimately conserving ocean seaweed. 'Our goal is to nurture tastier sea urchins on land and market them to combat ocean desertification,' Harada concluded.

(With inputs from agencies.)