Bottom trawling gets a bum rap, CSUMB study finds.

Bottom trawling—dragging nets along the sea floor to catch species like halibut and sanddabs—isn't always the destructive fishing method it's made out to be, according to a collaborative study by fishermen, The Nature Conservancy and CSU Monterey Bay.

The study, published in National Marine Fisheries Service's Fishery Bulletin, found that not all sea floors are created equal. The "soft" sea floor (mostly mud and sand) that comprises up to 85 percent of the continental shelf off the California coast may be able to recover quickly from small footrope trawl gear, the study concludes. Yet most of the state waters and much of the federal waters are closed to bottom trawling.

"Our study adds to a growing body of literature from around the world showing trawling impacts are context dependent—they depend on the type of gear used, the types of habitats trawled and how often trawling occurs," a press release states. "Trawling in rocky areas with long-lived corals will likely have more long-lasting impacts than trawling in soft-bottom habitats that may be less vulnerable and can recover more quickly."

Monterey Bay Aquarium's Seafood Watch guide, which has long shunned much of Monterey Bay's own local catch because it viewed bottom trawling as environmentally unfriendly, is now picking up on that more nuanced approach. The updated Seafood Watch guide upgraded 21 species of West Coast groundfish from red (avoid) to yellow (good alternative) or green (best choice) rankings, as the Weekly reported last fall.

Also promising: next-generation light-trawl gear that floats just above the sea floor instead of dragging. Environmental Defense Fund consultants Huff McGonigal and David Crabbe developed the technology to allow fishermen to "fish a wider area, travel faster, reduce fuel costs by a quarter and preserve bottom-dwelling fauna," as the Weekly reported in 2013.