Old crab pots may revive oyster harvests

Could old crab pots, once destined for landfills, help revive North Carolina’s severely depleted oyster population?

Faculty from UNC-Chapel Hill’s Institute of Marine Sciences in Morehead City are working with local fishermen to test the idea and transform derelict crab pots into oyster habitats. The trash-to-treasure project underscores the connection between healthy habitats and healthy fisheries, according to Joel Fodrie, assistant professor of coastal biological oceanography, who is heading up the research effort.

The idea was born from a simple observation. “Out on the water we all come across abandoned or lost crab pots covered with oysters,” Fodrie said.

Oyster larvae need hard substrate to settle on, and the crab pots keep them higher in the water column by creating a vertical refuge.

Obtaining raw material for the ongoing project is not a problem for the research team that includes Fodrie’s institute colleagues Niels Lindquist and Tony Rodriguez and commercial fishermen David “Clammerhead” Cessna and Adam Tyler. From 2010 through 2012, N.C. Division of Marine Fisheries’ Marine Patrol officers pulled more than 1,800 abandoned or lost crab pots, and they are happy to recycle them.

The team of researchers prepares the pots by cutting exits to eliminate unintended by-catch. They deploy them across varying environments and at different depths to identify conditions that help enhance oyster survival.

The pay-off is not just a boost in seafood production. Oysters provide habitats for young fish, erosion protection along coastlines, and water filtration. They are efficient little eco-workers, filtering the water of pollutants, bacteria, and algae. Besides, the project is keeping hundreds of crab pots from adding to bulging coastal county landfills.

Preliminary results from the team’s first full year of sampling are encouraging, and they are inspiring additional research.

Professor Niels Lindquist, for example, has launched a second project, deploying crab pots to tidal creeks, which have traditionally received little attention in restoration efforts. The crab pots have become portable laboratories that can be placed at the mouth of small creeks to catch the larvae and then moved further up the creek into intertidal, low salinity areas to foster survival.

In all of these projects, institute researchers are partnering with local fisherman and state environmental agencies to increase their odds for success.

“Our lab is committed to interacting with people who interact with the water. It’s enlightening for all of us. We learn from people who have a wealth of experience in and on local waters. In turn, we teach them scientific methods to collect data, ” Fodrie said.

For downeast fisherman Cessna, who holds one oyster lease and manages two others, collaboration “brings hope that we can fix some of the problems that threaten the commercial fishing industry. The bottom line is that we are working together to save our precious resources for all citizens.”

Oyster harvests in North Carolina have shrunk to an estimated 1 percent to 5 percent of what they were 100 years ago.

The ongoing restoration projects are funded in-part by grants from the Albemarle-Pamlico National Estuary Program, or APNEP, and the N.C. Sea Grant Fisheries Resource Grant Program.

Published July 9, 2012.