Black Sea Bass Season is starting up; Do you know about the bends?

ABOARD THE OCEAN EXPLORER, in the Atlantic Ocean east of Shark River — As a complement of anglers reeled in black sea bass from the ocean floor this summer, a New Jersey Sea Grant Consortium-assembled cadre worked to tag and release undersized fish with the bends.

Mike Danko, the NJSGC marine recreation extension agent for fisheries and boating, assembled a team consisting of two scientists from NOAA James J. Howard Marine Sciences Laboratory at Fort Hancock and from the American Littoral Society.

They were out on the 100-foot charter to identify fish with barotrauma, — commonly known as the bends — tag them and return them to the ocean floor via a descending device. More importantly, they were there to educate fisherman about barotrauma.

“We had informal discussions with approximately half of the customers on the way out to the fishing spot,” Danko said. “Slightly more than half of the people we talked with aboard the Ocean Explorer did not know what barotrauma is, but they all indicated they would be willing to use or try a descending device to increase survival rate of fish suffering from the condition.”

Barotrauma, otherwise known as the bends, affects animals that ascend from high pressure environments like the ocean floor, to low pressure environments like the ocean surface too fast. Gas builds up inside the animals, their eyes become bloodshot and bulge among other symptoms.

The end result is that a fish with barotrauma ends up floating on the surface like a beachball. The fish becomes easy prey for sea gulls and other predators.

Virginia Sea Grant partnered with the New Jersey and North Carolina Sea Grant programs and charter boat captains to develop and test, with funding from National Oceanic and Atmospheric Administration, new fishing gear—descending devices—to bring released fish below the surface and improve survival.

The technique for catching black sea bass is to reel them up as fast as possible in a constant motion. The fish are given no rest on the way up because the fish will attempt to swim back to the floor increasing the chance that they will fight free of their hook.

The technique impacts the smaller, younger fish that need to be thrown back. But the gas build-up inside the fish makes it difficult for the fish to swim to depth and many die on the surface.

The black sea bass season is currently closed, but it reopens on Oct. 22 with a with a 15 fish per day limit. A keeper is 12.5 inches. The season runs until the close of the year.

How it works

The device is a tubular net, with one end closed and the other open.

As anglers catch fish, they put the ones they want to release into the net. To release the fish, the hoop-net is dropped overboard. The device falls through the water with the opening facing down; the weight of the hoop pulls the net down, fish and all.

“Remember, each fish is like a balloon and has a buoyancy factor that must be countered,” said Bob Fisher, Virginia Institute of Marine Science extension staff affiliated with Virginia Sea Grant and one of the researchers on the team.

The hoop must weigh enough to sink despite the little fish “balloons” floating in the net. The fish’s air bladder recompresses as it is pulled down, and the fish regains the ability to swim out on its own.

The test runs this summer off the New Jersey shore were very successful, Danko said.

During the trip, 30 black sea bass and 2 tautog were tagged by Jeff Dement  from the American Littoral Society. And on July 11, 2015, an angler captured one of the tagged fish in the vicinity of where it was released.

“From what we can tell the device works well, Danko said. “ However, additional tag and release studies are need to determine survival rates.”