科学美国人60秒:Crop Rotation Works in the Sea, Too

Crop rotation is a recognized way to keep soil and the food ecosystem healthy. Now, scientists are saying that rotation could be a useful tool—in the sea.

Researchers tracked a shallow-water, near-shore species used for food: sea cucumbers. They’re easy to harvest and are fairly valuable. But those same attributes mean they’re easy to overharvest. The practice has put some sea cucumber species at high risk of extinction, even in a relatively well-managed area, the Great Barrier Marine Park in Australia.

In 2004 authorities split the Great Barrier Reef into 154 zones, where each zone was fished only once every three years. Fishers rotate through the region. In computer models, the researchers ran through dozens of simulations of each zone, both before and after the divisions took place. The trials revealed that even with an identical and low-catch allowance in all cases, the sea cucumbers would recover more fully under the rotation strategy than by harvesting simultaneously  throughout the region. In fact, in trials that included rotations, the yield actually increased. The research is in the Proceedings of the National Academy of Sciences. [Éva Elizabeth Plagányi et al, Crop rotations in the sea: Increasing returns and reducing risk of collapse in sea cucumber fisheries]

The scientists say their results suggest that such rotation might be beneficial in these kinds of shallow marine regions around the world, particularly for species that are in high demand. Because you should not eat your seed corn. Or your seed sea cucumbers.

—Cynthia Graber