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Two-for-One Fisheries Research
By Julie Herndon, Cooperative Research Reporter
Northwest Atlantic Marine Alliance
The Times Record
A newly-built 46' Wesmac stern trawler from Sebasco Harbor has become a popular 'platform' for fisheries research and its captain, Proctor Wells, couldn't be happier. On a recent trip 16 miles offshore of Portland, scientists from not one, but two, research projects boarded the F/V Tenacious.
With money appropriated by Congress specifically for this purpose, 'collaborative' research has become the buzzword in both fishing and scientific communities. The idea is that utilizing fishermen's experience and knowledge will improve the science on which fisheries management decisions are made. The ultimate goal is to insure good stewardship of marine resources and the human communities which depend upon them.
Wells, a third-generation commercial fisherman from Phippsburg, had the Tenacious 'built with research in mind.' Wesmac added four feet to the stern of its 42' hull to increase deck space for research work. The Tenacious also has an uninterruptable 110 power supply for computers, hydraulic oil cooler to handle the stress of shorter, more frequent research tows, a comfortable wheelhouse complete with a work table, and plenty of bunk room. It recently passed a voluntary Coast Guard Safety inspection.
On this trip, Wells was helping the Manomet Center for Conservation Sciences to conduct commercial trials of otter trawls with modified codends in an effort to reduce 'bycatch,' in this case - the unintended mortality of juvenile, commercially valuable fish.
"I felt the need for some good scientific data in the groundfishery" Wells stated, "and I was curious about the selectivity of different codends".
When asked how he became involved in this project, Wells reports that he was approached by Dr. Chris Glass at the Maine Fishermen's Forum. Glass, the Director of Fisheries Research at the Manomet Marine Program, is highly respected in the field of selective gear research.
For this project, Glass enlisted three New England commercial fishermen to conduct the commercial trials. Manomet field researchers Gregg Morris and Tim Feehan have been working alongside Massachusetts fishermen Frank Mirachi of Scituate and Russell Sherman of Gloucester. Mirachi, captain of the F/V Christopher Andrew, completed four days of trials this past January. Russell Sherman, captain of the F/V Captain Dutch, made his tows in March and April.
Now it was Wells turn to christen the Tenacious for its first research trip. After steaming 16 miles through fog that cloaked nearby tankers, the Tenacious arrived in a 'rolling closure' area that Wells had determined would be best for conducting bycatch trials. Fishermen's knowledge and experience regarding fish concentrations is one reason scientists find collaborative research so inviting. Morris specifically sought out Wells' input when determining the location for the trials.
Morris, who started his career with a three-year stint as an observer, stated that Manomet's mission is 'science for sustainability' that also 'keeps people working'. "All of Manomet's work is collaborative", Morris stated. "We're finding ways to reduce problems but maintain catch - just harvest the adults, not juveniles".
He reported that the aim of testing composite codends is to find the best mesh that retains the maximum amount of legal-sized fish and releases the maximum amount of undersized fish. Previous studies have shown that diamond mesh is good at releasing undersized flatfish but catches small 'gadids' (cod, haddock, pollack). Square mesh tends to release juvenile gadids but catches small flatfish. The 'composite' of square and diamond mesh is an effort to blend the best of both shapes. "With fishermen, we can help find the answer to minimize bycatch," Morris said.
Upon arrival at the predetermined location, Wells' first mate, Randy Smith of Woolwich, let out the gear for the first tow with help from the researchers. Smith, who recently passed his captain's license exam, is a former coach and chemistry teacher at the Hyde School in Bath.
The experimental design of this project required a series of tows. The fishermen used their own gear, except for the experimental codends. Wells tows a 100' rockhopper groundfish net with cookie-covered ground cables and #6 Bison doors.
On the first day of trials, the fishermen towed their conventional 6" diamond mesh codends eight times for twenty minutes or less each time. Russell and Mirachi also towed their commercial 6 ½" square mesh codends. In a method called 'absolute selectivity', the only modification on these tows was a 2" diamond-mesh cover placed over the codends to catch the fish that normally would escape. By comparing the catch in the codend to the catch in the cover, researchers are able to calculate the percentage level of bycatch. This approach is an improvement over 'trouser trawls' that utilize side-by-side codends to compare results. In the Gloucester trials, the researchers also used a video camera inside the cover aimed at the codend. This allowed them to record the behavior of the fish escaping the different codends.
On the second day of towing, Wells switched his codend to a composite mesh made up of 6 ½" square mesh over 6 ½" diamond mesh and then made six short tows. Day #3 was six trawls of 6 ½" square over 6" diamond mesh and two tows of 6" hexagonal mesh. The trials ended on the fourth day when the final four tows of hexagonal mesh were completed.
A flurry of activity ensued once Smith hauled back the net. The catch from the codend and cover was dumped into separate trays for comparison. Morris and Feehan quickly separated the species into orange baskets and then weighed and measured the commercially valuable species including dabs, haddock, cod, monkfish, redfish, grey sole, yellow tail flounder, winter flounder and pollack. The remaining species were simply weighed. These included herring, silver hake, red hake, white hake, four-spotted flounder, spiny dogfish, longhorn sculpins, shad and sea ravens. Any cod were handed over to a third researcher, David Martins, to be placed in a live tank for tagging.
Martins, a fisheries technician from the University of Massachusetts School for Marine Science and Technology (SMAST), had joined the Manomet researchers on the last two days of the project. In a gesture of scientific cooperation, Morris had invited him along so that he could continue his own research involving fish tagging. Since August 2000, SMAST has tagged over 6000 fish, mostly cod, but also halibut, haddock, spiny dogfish and striped bass. SMAST conducts some 'dedicated' trips to do tagging in closed areas but also trains fishermen to tag opportunistically.
Most of the tagging has been conducted in the southern Gulf of Maine, Cape Cod Bay and off Provincetown, so this trip on the Tenacious gave Martins an opportunity to expand his tagging efforts. SMAST has trained over 60 fishermen from Massachusetts, New Hampshire and Maine, and on this day, Martins would leave a tagging kit with Wells.
Martins reports that there have been 109 returns of tags. Some of the tags revealed interesting and unexpected results, such as fish crossing the 42° 20° line from the Gulf of Maine to Georges Bank or one fish that moved from Cape Cod Bay to the Race, near Nauset. A fish tagged on Stellwagen Bank was picked up off Jeffrey's Ledge. Researchers were surprised by the fish moving that far north. There has been one return from a halibut that 'didn't move too far'. Some fish showed southward movement in the spring when northward movement is expected. Massachusetts lobstermen, Phil Mason, captain of the F/V Kestrel and his son Peter, captain of the F/V Potluck, have tagged and recovered the same fish from the same trap area. "In fact, the same fish has returned to the same set of traps a couple of times within a month," Martins said.
At a price tag of $100 each, Martins reports that SMAST has also deployed 90 data archival tags that record temperature and pressure while implanted in the fish.
When asked about growth rate information, Martins stated that this has been unreliable.
Fished that were being tagged at 24" were being picked up later at 23".
Both studies aboard Wells boat aim at improving management of Northeast fisheries. The tagging study will help managers better understand movement of commercially valuable groundfish. This has implications for management tools such as time/area closures. The selective gear study aims at developing commercially viable ways of reducing bycatch - a management tool that may be more palatable to fishermen than days-at-sea reductions.
Morris summed up selective gear research. "There are workable solutions. Let's find them. Let's put our concentration there. There are ways to bring in what we want and not catch what we don't want." In a reference to closures, Morris stated than improving the selectivity of gear is better than drawing 'lines in the ocean".
Feehan emphasized that the take-home message of collaborative research is that it shows 'how fishermen are coming up with great ideas.....teaming up with scientists to do the work to generate good data and workable solutions to fisheries problems.' He emphasized Morris' point about fishermen's knowledge of fish concentrations. "Our experiments don't show anything if the fish aren't there."
The Manomet study, funded last year by the Northeast Consortium, represents only one of several ongoing collaborative efforts to improve management of Northeast fisheries. To learn more about Manomet and the Consortium, visit their websites at www.manomet.org and www.northeastconsortium.org . For help in getting involved in collaborative research, check out www.fishresearch.org.
And if you catch an SMAST-tagged fish, you may contact Dave Martins by phone at 508-910-6392, by fax at 508-910-6371 or by e-mail at dmartins@umassd.edu. Tag number, time and date of recapture and location information in LORAN coordinates or latitude/longitude are the most important information. Additional useful information includes size of fish, depth the fish was caught, substrate type, reproductive conditio, water temperature and gear type. Fishermen must re-release fish under legal size with tags intact. An SMAST cod-tagging hat will be mailed to callers who report a tagged fish.
Julie Herndon is the Cooperative Research Reporter at the Northwest Atlantic Marine Alliance (www.namanet.org), a Saco-based non-profit organization dedicated to restoring the marine ecosystem while protecting the livelihoods of fishermen. She may be contacted at julie@namanet.org.