Project Report:
Development of a low-impact semi-pelagic (LISP) trawl
- Explores and develops market-based solutions.


The purpose of this project is to support fishermen in New England’s struggling ground fish fishery in the purchase of environmentally friendly semi-pelagic trawl doors and a fuel flow meter. The scope of work has evolved significantly since original proposal submission primarily because the necessary funding was not available. In response, the Alex C Walker foundation granted GMRI permission to redirect available funds toward a novel financing model designed to support uptake of gear modifications by fishermen struggling to survive the dual impacts of reduced landings of cod and other ground fish and increasing fishing costs. The project also creates an opportunity to realize a seldom achieved twin benefit of increased profitability and reduced environmental impact – in a previous study GMRI compared semi-pelagic trawl doors and traditional bottom tending doors and found a fuel saving of 10% and a reduction in seabed contact of 95%.

Diagram of Semi Pelagic Trawl Doors
Comparison of standard and improved trawl nets. Standard bottom-dragging net doors (top) damage fish habitat. The improved net with semi-pelagic doors reduces bottom damage and requires less fuel for the same catch.


The current project involves the development of a unique funding model spearheaded by GMRI in collaboration with Coastal Enterprises Inc. (CEI), the Alex C Walker Foundation, and GEARNET, a NOAA sponsored research project led by GMRI and the Massachusetts’s Division of Marine Fisheries. The model provides fishermen low interest finance with highly flexible loan repayments capped at 10% of their annual fuel costs. In addition, each fisherman that signs up for this finance is provided a $2,000 subsidy from the Alex C Walker foundation to offset repayments or other fishing costs. Should a large number of fishermen sign up for this finance, the GEARNET project would step up and provide additional $2,000 subsidies.

Once fishermen have signed up for the finance and installed the fuel flow meter, they collaborate with GMRI to provide fuel consumption details to compare their traditional trawl doors and the new semi-pelagic trawl doors. This information is then made available to other fishermen to serve as evidence of semi-pelagic door and fuel meter performance.

With the addition of a fuel flow meter, fishermen will for the first time be able to make adjustments to boat speed and instantaneously assess the impact on fuel consumption. Combined with an estimated annual fuel saving of 5% possible through these adjustments, this funding model is estimated to save some fishermen over $50,000 per year and payback of finance within 6 months. Importantly, by capping loan repayments against annual fuel costs, fishermen are able to make their repayments from fuel savings instead of digging deeper into their pockets.

While the New England ground fishing industry continues to struggle in the face of recent cuts in fish quota, four fishermen are enjoying the fuel-saving benefits of using semi-pelagic doors. With support from the Alex C Walker Foundation, these fishermen were able to finance the purchase of these doors and a fuel flow meter which have reduced fuel use by an estimated 8 – 12%. All fishermen are extremely grateful for the opportunity to participate in this program, and cited the financial support of the Alex C Walker Foundation as key in their decision to participate in this initiative. In addition, they are also reducing seabed contact by as much as 95% compared to traditional, bottom-tending doors.

With at least six months experience using the doors and meter, the four fishermen were recently provided a brief questionnaire to gauge their perceptions of door and meter performance and to better understand how they are using this equipment. All fishermen indicated they consistently use the doors when targeting groundfish, and two were using the doors when targeting squid, summer flounder or other species. One fisherman did not use the doors when operating in shallow water (< 40 fathoms) where clear ground is limited and tidal strength is high, preferring traditional doors which offer greater control over the trawl gear. In other conditions this fishermen returned to using the semi-pelagic doors. All fishermen indicated the doors barely contacted the seabed, yet there was no discernable loss of target catch. Similar to traditional doors, fishermen reported greater trawl spread when towing into the tide compared to against the tide, although one fisherman thought this also increased his catch of flounder. Most responses from fishermen indicated they were quickly able to use these doors using instructions provided by the supplier, although two indicated the doors are so efficient that overspreading (excessive horizontal spread, which can reduce fish catches) can be an issue, and one has subsequently reduced the size of his doors to overcome this issue. Three fishermen were using acoustic door sensors to monitor door performance; the fourth fisherman was able to satisfactorily operate the doors without these sensors.

All four fishermen continue to use and be very satisfied with the semi-pelagic doors and would not return to the traditional type if given the opportunity. One fisherman reported his fuel savings had already amortized the initial door cost, hence further fuel savings mean more dollars in his pocket. Estimates of fuel savings from the remaining fishermen suggest that they too are getting closer to amortizing the initial cost of the doors. All fishermen are very satisfied with the fuel meters, citing greater awareness of fuel consumption under a variety of operating conditions as a result. This awareness has led to adjustments in engine revolutions to further conserve fuel, especially when in transit to and from the fishing grounds.

We consider this project highly successful with all four fishermen now enjoying an average fuel saving of 10% annually. These fishermen have now also significantly reduced seabed contact, and are much more aware of their fuel consumption and the operational circumstances that influence this consumption. This is a win-win outcome for the environment and fishermen that can only serve to encourage other fishermen to adopt this equipment in the future. Furthermore, as news of this project spreads across the fishing fleet, greater numbers of fishermen using this equipment are expected in the future. To support this expectation, a project with GMRI involvement known as GEARNET ( has recently leased 3 sets of semi-pelagic doors for the next two years and made them available to fishermen to test at little or no cost. This provides fishermen a unique and low-risk opportunity to access and test these doors over one or more fishing trips and gain a better idea of their fuel-saving potential before deciding upon their purchase.

In an industry presently overwhelmed with distraction, the implementation of fishing gear modifications such as semi-pelagic trawl doors has not been the uppermost concern of New England groundfish fishermen. Nevertheless, a small but growing number of fishermen are demonstrating their value in both economic and environmental benefits. Four fishermen recently made the shift from traditional doors to the semi-pelagic doors, with support from the Walker Foundation in the form of a substantial rebate on their purchase cost. With only about 15 boats on the entire US east coast currently using these doors, this small number is still significant.

All four fishermen are very satisfied with the new doors and would not return to the traditional type. They report substantial fuel savings, with estimates around 10%, and no loss of catch. While there are no further funds available for additional rebates on the doors, interest among other fishermen remains high. We will continue to collect data and track the experience of the current group, and relay the information to the larger fishing community as they consider their futures.

As is often the case, it will likely be the conversation from fisherman to fisherman that carries the greatest impact. Captain Dan Murphy of the F/V Bantry Bay participated in the project. He was provided with a fuel meter and low-drag twine from GMRI’s GEARNET project, purchased the doors himself and was then provided a rebate from the Walker Foundation. His vote of confidence after completing several fishing trips with the new gear speaks volumes for the opportunity:

"I would like to express my gratitude to be involved with this project. I have always wanted to try a net with smaller diameter twine, but the high cost of buying one deterred me. I knew the net would tow easier and there would be fuel savings, but didn't know how much savings. I am amazed with the results. I am towing a larger net easier with less fuel consumption and with an increase in my catch. The new net coupled with the Flow Scan really gave me assurance that efficiency and savings are really there. Excited about the results of the new net I wanted to take a step farther and purchase a set of Semi-Pelagic Doors. With the help of GEARNET and the Walker Foundation I was able to get a rebate to help pay for the doors. The new doors are Fantastic! Right away I gained over 1/2 knot of towing speed. With my old gear I had to push the engine to get 2.8kts, but now I can tow over 3kts. This was a very educational project and it will be interesting to see what the savings will be over time."

At the end of 2013 four fishermen had taken up the opportunity to purchase semi-pelagic trawl doors and a fuel flow meter, the maximum number that could be funded using this Award. All fishermen are very satisfied with their new doors, claiming fuel savings in excess of 10% and little, if any, discernable difference in catch compared to traditional doors. They have also indicated substantial fuel savings based on frequent adjustment of engine revolutions to optimize fuel consumption – something that can only be achieved using a fuel flow meter to provide real-time fuel consumption data – when fishing and steaming to and from the fishing grounds. Data collection by these fishermen is ongoing and in 2014 these data will be collected and analyzed in greater detail. Noteworthy is that each fisherman has now effectively reduced door-induced seabed impact by 95% in comparison the traditional doors.

To date, almost 20 ground fish fishermen have expressed an interest in this financing project although only one has followed through and purchased the semi-pelagic trawl doors and fuel flow meter. Many fishermen are in a holding pattern, talking time to consider how recent changes in cod abundance and associated catch shares will affect their fishing operation, hence we expect an escalation in the numbers of fishermen signing up for this model in coming months as they realize the unique opportunity this project provides.


By providing low interest finance to fishermen we expect to reduce fuel consumption and costs by at least 10%. This will provide significant relief for fishermen from high and ever-increasing fuel prices, contribute substantially to their profitability, and help revitalize an economically depressed fishery. This financing model is unique, and we believe provides a benchmark in terms of flexibility and institutional support against which other financing models for the fishing industry should be measured. Moreover, such gear may pave the way for fishermen to access new, niche markets for their seafood that until now have been closed to trawl-caught product, particularly because the new doors reduce environmental impact.


The results of this project will potentially benefit a number of New England ground fish fishermen so they can remain viable and competitive in an environment characterized by increasing fishing costs and dwindling profitability. This work will also contribute significantly to efforts to identify and generate successful financing mechanisms for fishermen to purchase and adopt new fishing gear. Many fishermen would like to conserve fuel and reduce environmental impacts but are unable to finance the cost of new gear; this unique effort is designed to leverage opportunities to financially support fishermen that can also realize a suite of positive environmental outcomes in terms of reduced seabed impact, consumption of fossil fuel, and release of greenhouse gas emissions.

Amount Approved
$20,000.00 on 6/4/2012 (Check sent: 7/2/2012)

Groundfish Trawler

Groundfish Trawler
Diagram of Semi Pelagic Trawl Doors
Camera attached to semi pelagic doors

350 Commericial Street
Portland, ME 04101

(207) 772-2321
(207) 772-6855 (fax)


Donald Perkins
President, Gulf of Maine Research Institu
Jill G. Harlow
Advancement Strategist, Gulf of Maine Research Institute
Mr. Jonathan Labaree
GMRI Sector Initiative Program Manager
Steve Eayrs
Scientist, Fish Behavior & Gear Technology

Posted 4/1/2012 12:01 PM
Updated   7/14/2014 11:01 AM

  • Nonprofit

Camera attached to semi pelagic doors
GMRI researchers have used underwater cameras to get a better sense for how semi pelagic doors perform

© 2024 Alex C. Walker Foundation