**NMFS National Standing Working Group on Fishing Technology**

**Report of First Meeting, March 6-7, 2002**

**U.S. Department of Commerce**

**National Oceanic and Atmospheric Administration**

**National Marine Fisheries Service**

**Introduction**

The first meeting of the NMFS Standing Working Group on Fishing
Technology (FTWG) was held at the Northeast Fisheries Science Center,
Woods Hole, on March 6-7, 2002. In attendance were:

Christopher Boggs \* NMFS Southwest Science Center (F/SWC2)

Alan Blott \* NMFS Northeast Region (F/NER)

Val Chambers \* NMFS Headquarters (F/SF3)

Ned Cyr \* NMFS Headquarters (F/ST)

Henry Milliken \* NMFS Northeast Science Center (F/NED32)

Craig Rose \* NMFS Alaska Science Center (F/AKC2)

Waldo Wakefield \* NMFS Northwest Science Center (F/NWC42)

John Watson \*\* NMFS Southeast Science Center (F/SEC4)

Arne Carr \*\*\* Massachusetts Division of Marine Fisheries

Joe DeAlteris \*\*\* University of Rhode Island

Cliff Goudey \*\*\* MIT Sea Grant College Program

Chris Glass \*\*\* Manomet

Pingguo He \*\*\* University of New Hampshire Sea Grant

Mike Pol \*\*\* Massachusetts Division of Marine Fisheries

Ron Smolowitz \*\*\* Coonamessett Farm

\* working group member

\*\* working group chair

\*\*\* invited presenters

Agenda items for the meeting were:

-   Review of draft terms of reference

-   Review of fishing technology research

    -   Alaska Fisheries Science Center

    -   Northwest Fisheries Science Center

    -   Southwest Fisheries Science Center

    -   Southeast Fisheries Science Center

    -   Northeast Fisheries Science Center

-   Review of national recommendations for addressing bycatch

-   Review of budget and staffing needs by region

-   Review of New England ground fish fishery bycatch issues

John Watson opened the meeting with a discussion of the need and purpose
of the group as expressed by the NMFS Science Advisory Board. Mike
Sissenwine welcomed the group to the Woods Hole Laboratory and gave a
brief presentation on the New England fishery and the status of
litigation concerning the New England groundfish fishery. Bill Hogarth
addressed the group via teleconference. He briefly reviewed bycatch
issues from the national perspective and charged the group to review the
national recommendations on bycatch and provide recommendations on
funding and personnel requirements to address bycatch issues. He
indicated a budget initiative was being prepared for gear technology
research in 2004 and requested input from the group on regional needs.
Bill also asked the group to address the New England groundfish bycatch
problem and provide recommendations.

**Terms of Reference**

Draft terms of reference for the working group were reviewed. The
mission, composition, and responsibilities of the NFTWG were discussed
in detail and changes to the draft agreed upon. The group discussed
possible overlap between the fishing gear technology working group and
the sampling technology working group and concluded that while there may
be technologies that would be common to both endeavors, the missions
were distinctly different. The two groups should, however, share
information on new technologies that may be applicable to both group's
research needs. The NFTWG members discussed the current status of
research on fishing gear technology and the general consensus was that
there is a critical shortage of personnel within NMFS to conduct fishing
technology research. There are industry, state, university, and private
organizations conducting fishing technology research and the group
stressed the importance of coordination and communication between these
organizations and the NMFS Fishing Technology Working Group. The Group
recommended that NFTWG meetings be rotated between regions in order to
facilitate coordination and communication with non-NMFS researchers in
each region. The group also recommended that the NFTWG have an advisory
role in management decisions concerning bycatch/gear technology
priorities and research direction. It was recommended that a permanent
representative from both the Science and Technology and Sustainable
Fisheries Division be included in the NFTWG to facilitate better
communication and coordination with NMFS managers. The revised NMFS
Fishing Technology Working Group Terms of Reference are provided in
Appendix I.

**Review of Fishing Gear Technology Research**

**Fishing Technology Research by the Alaska Fisheries Science Center**

Through a mix of cooperative and direct research, NMFS scientists have
assumed a critical role in the improvement of fishing technology used in
Alaska waters, and aided such developments in other regions. Our efforts
have emphasized NMFS capabilities that complement the efforts of
industry, including specialized observation equipment, behavior
research, and experimental, testing and analysis abilities. There are a
growing number of opportunities to reduce fishery problems through
improvements in fishing technology and NMFS is positioned to serve a
critical role in such efforts, limited by staff and funding.

Federal fishing technology research in this region includes work by the
Seattle Exploratory Fishing and Gear Research Base in the 50\'s - 70\'s.
Gear development to facilitate fisheries expansions was emphasized,
including midwater trawls, traps and survey gear. Some devices to avoid
bycatch were also developed*. In situ* observations were made by scuba
divers.

In the late 70\'s, the work was halted on commercial gears and limited
principally to gear used in resource assessment surveys. Accomplishments
during this period included prototype development and application of
trawl mensuration equipment to monitor the performance of survey trawls.
Such equipment was added as a standard element of trawl surveys in the
late 80\'s, accompanied by increased standardization of trawling
procedures.

Beginning in the late 80\'s, cooperative research with industry and
other agencies brought the Alaska Fisheries Science Center's Resource
Assessment and Conservation Engineering (RACE) Division into an
increasing role in studying ways to reduce bycatch through the
modification of fishing gear, resuming historical work on commercial
gears. Recognizing that fish behavior is key to the selection process,
video systems were developed and used to remotely observe fish behavior
in trawls. Observation capabilities also sped the development of
prototype devices and methods for bycatch reduction. Observation systems
include a range of video systems using ambient, visible and infrared
lighting that can be operated either through cables or remotely
recording.

These observation systems have been used to understand variation in fish
behavior between species and under different environmental conditions.
Where needed, separation concepts are developed with these observations
and further tested and improved by observations on modified fishing
gears and comparisons of catch rates. Industry developed concepts are
similarly developed. All testing is done on commercial fishing vessels
starting with gear similar to that used in the fisheries. Separation
systems with sufficient promise are subjected to testing under full
fishery conditions, generally in an exempted fishery in cooperation with
industry.

Some examples of the devices developed and/or tested in this program
are:

-   Reducing halibut, cod and pollock bycatch in sole fisheries through
    opening the top of a section of the net ahead of the codend
    (intermediate section)

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-   Reducing halibut bycatch in sole fisheries with an
    industry-developed excluder grate in the intermediate section.

-   Development of separate devices to exclude large and small halibut
    from cod trawls

In addition to commercial gear development, these systems have been
applied to improving understanding of survey gear performance. Video
observations have supplemented studies of herding of fish ahead of
trawls and escape under the footrope, increasing our ability to
understand and interpret the population estimates derived from surveys
and the variability of those estimates. Sensors were developed by the
Fishing Technology group to continuously monitor the contact of trawls
with the seabed. Observation systems have also been developed to further
studies of fish habitat and the effects of fishing gear on it.

Another section of the RACE Division, the Fisheries Behavioral Ecology
Program, based in Newport, Oregon, has performed a range of laboratory
studies to develop basic fish behavior information for use in
understanding the fish selection and incidental mortality associated
with fishing gears. Important results include the effects of physical
factors (light level, temperature, air exposure, sea conditions) on fish
escape, injuries and mortality. Fish size controls mortality, with
smaller fish being more sensitive to stress. Delayed mortality appears
to be important and must be considered in field and laboratory
experimental design. There is also a wide variety of sublethal
behavioral effects resulting from bycatch stressors which decrease
predator avoidance capabilities and increase the probability for
mortality of escapees and discards.

A number of other agencies and institutions have conducted fishing
technology projects in the region, nearly all of which have availed
themselves of the opportunity to use the equipment and/or expertise of
the NMFS program. These have included:

-   A Saltonstall-Kennedy (NMFS) funded project by the Alaska Fisheries
    Development Foundation (AFDF), and the Universities of Washington
    and Alaska to study the size selectivity and escapee mortality of
    pollock in the Alaska fishery.

-   A joint project of the International Pacific Halibut Commission and
    the trawl industry to begin development of halibut excluders for
    trawls

-   A joint project of the longline industry and the University of
    Washington to develop and test devices to prevent seabird bycatch on
    longlines

-   Projects by Oregon Department of Fish and Wildlife to test fish
    excluders for shrimp trawls and a selective flatfish trawl and to
    study behavior of fish around fish pots.

Through cooperation with industry and other research groups, RACE
division scientists have greatly increased the effect of a very small
(in both personnel and funding) fishing gear research program on many
fishery issues that can be affected by better understanding and
performance of fishing gear, including bycatch, protected species
interactions, and protection of essential fish habitat.

**Recommendations from 'Managing Bycatch' 1998 - Accomplishments**

A review of the fishing gear-related recommendations for bycatch for the
Alaska region from the 1998 'Managing Bycatch' document shows some
progress on each, with substantial opportunities for continuing work.

-   [Conduct research on the survivability (acute and chronic mortality)
    and recovery of bycatch species from stresses imposed by
    capture]{.underline} - Work with the AFDF pollock survival project
    produced initial estimates of survival escapee mortalities and
    developed methods and equipment for use in future studies of this
    type. A study was completed on the injury rates of red king crab
    that encounter and escape bottom trawl footropes on the seafloor.
    The Fisheries Behavioral Ecology Group has clarified a number of the
    environmental and fishing factors that affect fish survival after
    encountering fishing gear. There a still an abundance of species
    that encounter and escape fishing gear for which mortality has not
    been assessed, as well as the need to estimate the variability due
    to the range of fishing situations in the fisheries. As new methods
    are developed for avoiding bycatch through gear modifications,
    assessment of escapee mortality and modification to improve survival
    will be necessary development steps. Progress in this area has been
    severely limited by the personnel and funding requirements of such
    research.

-   [Increase industry's involvement in the development and testing of
    methods to reduce bycatch mortality]{.underline} - Elements of the
    Alaska groundfish industry have been very active in the development
    of bycatch reduction devices, in many cases in spite of substantial
    individual costs in efforts where benefits of the work are dispersed
    through the entire fleet. NMFS gear researchers have facilitated
    these efforts through providing needed equipment and services as
    well as participating in the development and conduct of exempted
    fishing projects to allow testing by industry. There is a synergy
    between government research and developments by industry. The early
    stages of concept development often involve high costs and risks
    that are not compatible with normal fishery operations. Use of
    developing and experimental fishing gear and observation equipment
    produces delay and catch losses, while the need to test the effect
    on bycatch species requires increased encounters with those species
    at rates that would trigger regulatory consequences in the open
    fishery. Even additional catch opportunities provided under exempted
    fishery permits often do not compensate for losses to participating
    vessels. Therefore, government participation and funding is most
    useful and often critical during earlier stages. As bycatch
    reduction devices proceed to the point of feasibility in the
    commercial fishery, industry is much more able to complete the
    remaining development.

-   [Improve technology transfer of bycatch reduction methods through
    reports, videos and workshops]{.underline} - All three of the
    mentioned communication tools have been used to inform Alaska
    fishers (as well as fishery mangers and other scientists) of the
    results of bycatch reduction research, in addition to one-on-one
    contacts with gear manufacturers and fishermen. There is
    considerable room for increasing and improving communication with
    the fleet and with that opportunities for improving both the
    research and the fishery.

**Outlook for Fishing Technology Research in the Region**

**Needs**

The Alaska fisheries are unique in the nation in having very intensive
on-board observer coverage of the vast majority of the groundfish
fishing effort. Thus, discarded bycatch can be estimated and accounted
for in assessment and management. In most cases, however, no survival
information is available to do more than make the conservative
assumption that all discarded fish die.

There is no shortage of gear-related issues that could be addressed with
enhanced fishing technology research in the prosecution and management
of Alaska groundfish fisheries. These include bycatch reduction and
mortality assessment, effects of fishing gear on seafloor communities
and their reduction where needed, down to collecting basic information
on specifics of current fishing technology in the fishery. A listing of
potential projects follows.

Bycatch Reduction Developments

-   salmon bycatch in pollock trawl fisheries

-   crab bycatch in bottom trawl fisheries

-   better size selection in sole fisheries (reduce discards)

-   halibut bycatch in longline fisheries for cod

-   shark bycatch in pollock fisheries

-   skate bycatch in bottom trawl fisheries

-   crab injuries (mortalities) from trawl bridle (sweep) encounters

Survival studies

-   pollock, sole and cod escaping through meshes or excluders

-   halibut escaping through excluders

-   estimation of discard survival for all discarded species

-   measurements of environmental factors (light levels, temperature,
    air time, sea state) in gear, through water column and on board ship
    during landing and sorting of catch to link results with laboratory
    studies and better understand the range of conditions that bycatch
    are exposed to in fisheries.

-   measurements of fish size and body core temperatures of discarded
    bycatch to evaluate thermal history and relate this to environmental
    factors for making predictions of discarded bycatch stress and
    mortality.

Fishing gear surveys - Key specifics of gear used by fisheries

Effects of Fishing on Habitat

-   Fishing intensity and distribution analysis

-   Passive Gears - measurement of area affected while hauling gear -
    effects on habitat

-   Reduction opportunities -

Off-bottom doors

> harvest of pollock from very near the seafloor, while limiting
> seafloor contact

pot modifications to prevent seafloor effects

Improved communication with industry, management and other stakeholders

Improved technology for fish behavior observation

> Most of the fishing effort in Alaska waters occurs in waters dark
> enough to A) prevent observation with even the most sensitive cameras
> without artificial light and B) alter fish behavior from that which
> can be observed at higher light levels. Thus, there is a serious
> disconnect between our ability to observe fish behavior relative to
> fishing gear and the conditions that those fish encounter in the
> fisheries. The AFSC program has pioneered the use of infrared
> illumination to provide some observational capabilities, but this is
> limited to very short ranges. New sonar systems have recently been
> developed that allow fish observations without light at an update rate
> and resolution sufficient to observe fish behavior. These systems are
> currently beyond the budget of existing FT programs to procure (\$
> 90,000), but would provide a breakthrough in relevant fish behavior
> studies.

**Outlook with current resources**

> Current budgets allow continuation of work on this subject, but limit
> it to either pilot level studies on several of these areas or full
> studies on only one at a time over several years. We have taken the
> former approach and will work this year on salmon bycatch, crab
> injuries and effects of passive gears on seafloor habitats.

**Needs for fuller implementation**

Funds to procure \$90,000 sonar video in 2002

One additional research biologist in 2003, one in 2004

Gear technologist in one of those years

Funding base increase of \$200,000 in 2003, additional \$400,000 in 2004

**Fishing Technology Research by the Northwest Fisheries Science
Center**

**NO REPORT AVAILABLE**

**Fishing Technology Research by the Southwest Fisheries Science
Center**

Fishing technology research at the Southwest Fisheries Science Center
(SWFSC) since the 1970's was limited by a policy discouraging "fishery
development" research. However the SWFSC has been active in developing
gear modifications to reduce bycatch and especially to reduce
interactions with protected species. Historically, the gravest issues
have been those surrounded the taking of marine mammals, especially
dolphins in tuna purse seine operations. Most recently the primary
issues have been the take of albatross and sea turtles in longline
fishing operations.

Purse seine fishing that targeted yellowfin tuna associated with
porpoise in the eastern tropical Pacific was the focus of concerted
fishing gear research at the SWFSC for over 3 decades. Porpoise tended
to get stuck by the rostrum in the meshes of the seine as it was pursed
and drowned when they could no longer get to the surface. With the
expansion of purse seine fishing porpoise populations declined. An early
solution to the problem was engineered by the U.S. purse seine fishery.
This solution involved use of the "Medina panel" at the edge of the
seine in a position that leaves the panel farthest from the fishing
vessel as the net is pursed. This panel has smaller mesh than the rest
of the seine to prevent snaring dolphins, and is used to create a sort
of ramp from the vertical side of the seine to the upper edge of the
seine. When used properly this technology was very successful at
reducing porpoise kills, and widespread use helped lead to a recovery of
porpoise populations. However, national mandates for marine mammal
protection called for reducing porpoise catches to as close to zero as
possible. The low level of dolphin mortalities that continued to occur
in the U.S. fishery contributed to pressure on that fishery to depart
from the eastern Pacific, while less regulated Latin purse seiners
continued to set on porpoise.

The U.S. industry voluntarily adopted "dolphin safe" standards for tuna
accepted for canning, while the U.S. government pursued treaties and
trade sanctions to discourage the Latin American nations from setting on
dolphins. The SWFSC continued to address the problem by conducting a
wide variety of research efforts to develop "dolphin safe" purse seine
fishing technology such as improved spotting technology for
free-swimming tuna schools (e.g. radar, sonar, lidar) and use of fish
aggregating devices (FADs). Purse seine setting on floating objects,
including FADs, has a very low rate of interaction with porpoises but
tends to catch smaller, less valuable tuna and has a much higher rate of
fish and sea turtle bycatch than setting on porpoise. A steady increase
in "dolphin safe" purse seine sets on floating objects led to problems
with bycatch in the 1990s and eventually to international quotas for
this fishing method to limit bycatch of juvenile bigeye tuna in the
eastern Pacific.

One lesson learned from the tuna-porpoise fishing technology saga is
that progressive and successful development of improved fishing
technologies by U.S. fisheries may not help when national goals call for
minimization of protected species interactions at any cost. Setting on
dolphins with improved technology could have been sustained if the
nation's policy had been to achieve a recovery of the porpoise
populations. An amendment to Murphy's law also states that any
technological solution to one problem (e.g. dolphin mortality) will
simply lead to another (fish bycatch around floating objects).

The tuna-porpoise issue was one of several issues in which policy
aspects of international bycatch problems plagued SWFSC efforts at
technological solutions. A decade ago an international effort was
launched by NMFS with Japan, Korea, and Taiwan to scientifically monitor
bycatch in the high-seas drift gillnet fisheries, assess the impact of
this bycatch, and develop bycatch mitigation strategies. Participation
by the Honolulu Laboratory included placing observers on foreign vessels
and measuring bycatch and persistence of "ghost" fishing by derelict
drift gillnets. Midway into this international collaboration the U.S.
spearheaded a United Nations ban on all such fishing on the high seas,
alienating our research partners and terminating the research. Meanwhile
the same fishing method continued to be used within the U.S. EEZ. The
SWFSC continued working to develop gear modifications and sonic pingers
to reduce bycatch of marine mammals in the coastal drift gillnet fishery
for swordfish and sharks.

Work on insular fisheries technology for the central and western Pacific
at the Honolulu laboratory focused mainly on fisheries for crustaceans
and bottomfish. Deepwater shrimp trapping was developed to assess a
newly exploited stock in a very short-lived fishery. Escape vents were
developed for the lobster trap fishery in the Northwestern Hawaiian
Islands. Bottom longline gear including hook timers invented by Honolulu
Laboratory scientists was developed to gauge gear-saturation effects on
CPUE surveys. These hook timers were later modified for research on
pelagic longline fishing gear selectivity and hooked longevity of
longline caught fish. Hook timer research showed that marlin, spearfish,
and mahimahi caught on "deep" longline hooks were most often caught
while those hooks "troll" through the mixed layer during longline
retrieval and that such fish are seldom captured on hooks in or below
the thermocline during daylight hours.

The recent focus of fishing technology research has been on mitigating
longline gear interactions with albatrosses and sea turtles. Number
range CHAPTER Prior to the northward expansion of the Hawaii-based
longline fishery in1989-92, interactions with seabirds were probably
very rare, and turtle bycatch was probably less than 10% of what it
became in the 1990s. In the last decade virtually all seabird
interactions with the longline fishery were Laysan and black-footed
albatrosses whose range and nesting colonies were north of the
traditional tuna longline fishing grounds. From 1994 to 2000 the fleet
was estimated to catch several thousand of each species of albatross
each year. The short-tailed albatross is the only endangered bird that
may possibly interact with the fishery. During this same period longline
bycatch of about 400 sea turtles annually was predominantly loggerheads
and leatherbacks, also caught mostly north of the traditional tuna
longline fishing grounds. Area closures, an observer program, and a
limited entry program were established in the 1990s to limit and monitor
endangered sea turtle bycatch, with ancillary reductions of interactions
with protected albatrosses.

Seabird deterrent research began at the NMFS Honolulu Laboratory in 1997
with limited testing of bird-deterring streamer lines aboard the NOAA
ship *Townsend Cromwell*. In 1999 the *Townsend Cromwell* tested the
effectiveness of blue dyed bait, added weights, and towed streamer lines
in reducing contacts between albatrosses and mock fishing gear (gear
without real hooks). This study indicated that streamer lines reduced
albatross contacts with fishing gear by about 70%, and that blue dyed
bait or added weights reduced seabird contacts by about 90% for both
albatross species. Commercial fishery testing of seabird deterrents was
begun on regular commercial fishing trips in1998, under contract to the
WPRFMC. This study documented the effectiveness of strategic offal
discards, night setting, blue dyed bait, and towed streamer-lines for
reducing interactions with albatrosses. Reduction of interaction rates
with these deterrent measures for black-footed albatross ranged from 83%
reduction (strategic offal discards) to 95% (blue dyed bait), and for
Laysan albatross reductions ranged from 40% (night setting) to 91%
(strategic offal discards).

Mandated seabird interaction mitigation measures proposed by the WPRFMC
in 1999 focused primarily on modifications to fishing gear and
operations, and required fishermen to select among 6 seabird deterrent
measures (see albatross mitigation measures, below) when setting and
hauling longline gear. However, a subsequent USFWS Biological Opinion of
the Effects of the Hawaii-based Longline Fishery on the Short-tailed
Albatross called for all longliners to use strategic offal discards and
thawed, blue dyed bait. Longliners targeting tuna were also required to
use a line setting machine and weighted branch lines. And those
targeting swordfish were also required to set at night. The objective of
the November 2000 opinion was to prevent taking more than 2.2 endangered
short-tailed albatross per year (no takes have ever been observed).
These mitigation measures became mandatory in March 2001, except that
the specific provisions for swordfish longliners became moot because
that style of fishing was banned to reduce sea turtle bycatch.

**Albatross mitigation measures**

Strategic Offal Discards are defined as discards of bird-attracting
spent bait, offal, or other waste fish parts on the opposite side of a
fishing vessel from where the fishing operation is being conducted. A
very effective method developed by fishermen involves splitting and
trimming fat-laden swordfish heads so that they remain afloat at some
distance behind the fishing operations, drawing birds away from where
baited hooks are being deployed or retrieved. The strategy is to discard
at times when birds might be particularly vulnerable, such as when lines
stray farther from the vessel's hull or are brought nearer to the
surface while boating fish or removing tangles. Researchers originally
expected to see a reduction in interactions when spent bait and offal
was withheld. Instead they discovered that withholding increased the
rate of interactions because birds attention remained focused on baited
hooks.

Night setting was routine for Hawaii-based longline fishing operations
that targeted swordfish, but when part of a set occurred around sunset
or in twilight birds could still see and interact with baited hooks.
Night setting is defined as waiting to start a set until at least an
hour after sunset, and to finish it by sunrise. This measure is least
effective for Laysan albatross, which seem more able to detect food in
low light, including light produced by a fishing vessel. Longliners that
target tuna usually set in daylight but tend to have very low rates of
interaction with albatross due to their more tropical fishing grounds
and the fact that they set slack main lines that submerge more quickly
than the taught main lines set by longliners that target swordfish.

Blue dyed bait has only been effectively field tested in operations
targeting swordfish using squid as bait. The normally white squid is
much more difficult for birds to see when dyed blue with food coloring
because it blends with the background sea color. Dying involves soaking
the bait in food coloring which has the added advantage that the bait is
thawed prior to use which causes faster sinking and makes it harder for
albatross to reach. Dying bait a variety of colors was a practice
developed by fishermen to increase the attractiveness of bait to target
fish species. Fishermen noted a reduction in seabird interactions when
using blue dye. Target fish catch rates seem to be at least as good as
when undyed bait is used, and the food coloring is inexpensive. After
hearing of its effectiveness in the Hawaii fishery the Japanese fleet
began trying blue dyed bait as a seabird deterrent.

Towed streamer lines, also called "tori"(bird) lines were first
developed by Japanese fishermen to reduce loss of bait to scavenging
seabirds. They are the most widely applied mitigation measure in world
longline fisheries. Streamer lines act as either a "scarecrow" or as an
obstacle to the flight path of birds seeking to reach baited hooks
trailing out behind a fishing vessel. Birds can avoid streamer lines
when the vessel changes course or the wind shifts, drawing the streamer
off of the immediate area of the baited hooks. Streamers can also become
tangled in the fishing gear and broken. The suite of bird mitigation
measures required in the Hawaii-based fishery is unusual in that
streamer lines are optional, but this is because the other mandatory
mitigation measures are so highly effective.

Weighted branch lines were common practice in the Hawaii-based fishery
prior to any requirement for seabird mitigation measures. The formal
definition calls for a standard weight located close to the hook on each
branch line. This location may be somewhat more dangerous than the
traditional weight location because it places the weight close to the
hook where it may spring directly at fishermen when fish throw the hook.

Line setting machines are used to pull the main line off of the longline
reel at a speed that is faster than the speed of the fishing vessel
through the water. This produces slack in the main line so that it goes
directly into the water. Without a shooter the main line is pulled off
the reel by the drag of the water as the boat moves, and the main line
is suspended in air for some distance behind the vessel. An even more
effective mitigation device may be the underwater line setting machine.
The Audubon Society and NMFS began testing an underwater line setting
machine in cooperation with the Hawaii-based longline fishery in
February 2002. Results indicate 100% success in eliminating albatross
mortality and 98.8% success in eliminating albatross interactions with
longline fishing gear.

Annual workshops on protected species interactions were initiated by the
WPRFMC in 1996 with the first Albatross Workshop for Hawaiian Longline
Fishers, which reviewed albatross biology, laws protecting seabirds, and
mitigation techniques. The Australian book "Catch Fish Not Birds"was
translated into Korean and Vietnamese and disseminated to Hawaiian
longline fishers along with laminated cards with photographs of the
three albatross species detailing mitigation techniques. A second
Fishers' Workshop was convened in 1997 and a Black-footed Albatross
Population Biology Workshop in1998. NMFS Pacific Islands Area Office
(PIAO) began conducting annual Protected Species Workshops for fishermen
in 2000 to provide fishermen with technical training in how to reduce
the severity of protected species fishery interactions and mortality of
albatrosses, sea turtles and marine mammals. Attendance at the workshops
became mandatory for limited entry license-holders in 2001.

Number range CHAPTER**Sea turtle longline bycatch mitigation measures**

The goal of this research is to develop methods to reduce longline
bycatch and mortality of sea turtles resulting in 'sea turtle safe\'
longline fishing. Objectives are 1) to reopen the swordfish segment of
Hawaii longline fishery and 2) to develop methods of 'sea turtle safe\'
longline fishing for transfer to foreign longline fisheries. Categories
of research underway are: 1) Fishing experiments with Hawaii longline
industry; 2) Sensory and behavioral research using captive sea turtles;
3) Tracking sea turtles with pop-up satellite tags; and 4) Sea turtle
population simulation modeling.

Fishing experiments being conducted with the Hawaii-based longline
fishery starting in 2002 were designed to test various gear
modifications over 3 years. The largest effort was intended to test
whether minor, economically viable alterations to fishing gear and
operations would reduce turtle bycatch. This effort is not yet underway
due to permit restrictions. Bycatch reduction testing requires
substantial takes of sea turtles to detect significant effects. Other,
major changes in fishing gear and operations are being tested to see if
they are economically viable prior to testing for turtle bycatch
reduction. The largest element of the fishing experiments would have
involved about 12 swordfish longline vessels per year testing the use of
blue dyed squid bait and branch lines arranged \>40 fathoms away from
float lines on half of 1,040 research sets per year, with the other half
serving as the control. Support for this approach comes from experiments
with captive turtles showing avoidance of blue-dyed bait and analysis of
Hawaii longline fishery observer data showing that branch lines attached
\<40 fathoms from float lines catch the most turtles and have only
average success in capturing target fish species.

An Endangered Species Act Section 10 Research Permit obtained by the
Honolulu Laboratory in January 2002 allows several smaller experiments
to be conducted, but the main experiment awaits evaluation of a similar
experiment in the Atlantic. However, the Atlantic experiment was
designed to test a more moderate gear change than the Hawaii-based
experiment. Moreover, separate Pacific experiments are required because
pelagic longline fishing strategies and tactics differ between the
Atlantic and North Pacific Oceans. These differences in fishing
strategies and tactics are related to fundamental differences in oceanic
structure between the two oceans. The Atlantic fishery operates
primarily at edges of the Gulf Stream in ecosystem influenced by
relatively near shore environments and comparatively shallow habitats,
whereas the North Pacific operates in two mid-ocean ecosystems that are
markedly different from the Atlantic. The tuna segment of the Pacific
fishery operates near the edge of a mid-ocean gyre ecosystem influenced
by the North Equatorial Current, and the swordfish segment operates in
the mid-ocean Subtropical Convergence Frontal system marking the
boundary between the tropical and subtropical North Pacific.

The portions of the research that are underway in Hawaii are the testing
of stealth (camouflaged) swordfish longline gear and deep daytime
swordfish fishing to see if these modifications retain viable economic
performance. Stealth gear will also be tested on tuna longline gear.
Research is underway using hook timers and time depth recorders to
document when and where turtle bycatch occurs most frequently in the
sequence of longline deployment and retrieval. A piggyback project is
also testing large (18/0) circle hooks for catching swordfish. Smaller
circle hooks were tested by other researchers in 2000-01, but were found
to be less effective in catching swordfish that the traditional J-hooks.
Circle hooks may reduce the degree of injury to captured turtles.

As of May 31, 2002, five Hawaii longline fishing vessels on contract to
NMFS have conducted about 140 research sets (33 deep daytime sets, 33
stealth swordfish sets, 33 normal swordfish sets conducted alongside the
previous sets to serve as a control group, and about 40 sets with hook
timers and circle hooks). Two additional vessels will conduct tests of
stealth gear in tuna fishing operations this summer, bringing the total
fishing effort to at most about 250 research sets this season. The first
permit year will end July 31, 2002 or sooner depending on the mortality
of sea turtles in the experiments. As required by special conditions of
the permit, the experiments will cease if there is an observed or
projected estimated post-hooking lethal take of 1.0 leatherback or 4.0
loggerhead sea turtles. These special conditions drastically reduce the
research effort and the directed take of sea turtles far below the take
totals included in the permit. The annual report on the research is due
Sept 31, 2002. Start of the fishing experiments next season will be Dec
1, 2002..

There have been 2 loggerhead turtles captured and released alive so far
in the experiments. Both turtles were taken by unmodified swordfish
fishing methods (one by the control vessel operating alongside the
stealth and deep daytime vessels, and one by a hook timer vessel). The
vessels using modified fishing methods have not yet caught any sea
turtles. All results to date are preliminary, but we can say that it was
more difficult than anticipated to fish deep during the daytime. The
deep daytime swordfish fishing method, as constrained by the
capabilities of the vessel used, was not successful in achieving viable
catch rates of the target species (swordfish). Preliminary results
indicate that the initial stealth swordfish fishing gear was not as
economically viable as normal (control) gear, but with some
modifications, the stealth gear shows great promise of viable catch
rates for target species. No results are available yet from hook timers.
Preliminary results from testing large (18/0) circle hook versus J hooks
shows increased catch rates for bigeye tuna using circle hooks, but
substantially decreased catch rates for swordfish.

Experiments on captive sea turtles are being conducted to define
physiological and behavioral differences between sea turtle and target
species that may be used to develop new fishing gear and tactics to
reduce sea turtle bycatch and mortality. Captive turtle work is being
conducted in collaboration with academic experts and by NMFS scientists
at the Hawaii Kewalo Research Facility and the Galveston, TX laboratory.
Tests on captive sea turtles are being conducted to determine types of
bait, and other components of fishing gear and tactics that may reduce
bycatch of sea turtles but will not reduce catch of targeted species.
Experiments are underway to evaluate the color and odor of natural and
artificial baits that sea turtles may not be able to detect or which are
repulsive to turtles. Experiments are also being conducted to evaluate
various colors of light sticks (conventional and electronic) and the
intensity of light sticks that may be undetectable by sea turtles. So
far the research has shown that sea turtles are attracted to natural
colored squid bait and to red-dyed baits. Tests also show that Kemp\'s
ridley, green and loggerhead sea turtles clearly avoid blue-dyed bait.
Captive turtle studies to evaluate potential deterrent effects of baits
soaked in squid ink, urea, garlic, bitters, and Jabanero chili extract
have been unsuccessful -- turtles ate all of these baits. However,
studies with empty and baited containers confirm that turtles are
attracted to (and potentially repulsed by) odor emitting substances.
Behavior experiments indicate that juvenile loggerhead sea turtles are
attracted to conventional green light sticks but not pure yellow light
sticks. Electronic light sticks generate pure yellow light and are part
of the stealth fishing gear being tested by Hawaii longline fishermen.

**Recommendations from 'Managing Bycatch' 1998 -- Accomplishments**

Pacific Pelagic & Insular Fisheries Recommendations

-   [Increase research on immediate and post- release mortalities of
    animals encountering fishing gear]{.underline}. Number range
    CHAPTERSatellite tracking of sea turtles is revealing significant
    new information on sea turtle habitat, movement patterns, and
    post-hooking survival. Approximately 50 turtles have been tracked
    with conventional ARGOS transmitters. About 20 turtles have been
    tracked with 'pop-up\' satellite tags. Argos transmitters indicate
    that post hooking survival predominates for many months after
    release and the pop-up tags will indicate whether post-release
    survival extends to 6 months or longer. Post hooking survival is
    being correlated with the condition of released turtles. New work
    with "pop-up" tags has also been initiated to measure post-release
    survival of longline-caught sharks and sportfishing released
    marlins.

-   [Work closely with the Western Pacific Fishery Management Council to
    develop solutions to bycatch problems including transfer of
    knowledge and techniques to reduce bycatch of seabirds in the
    longline fishery]{.underline}. As indicated above we have made very
    substantial progress on this and in similar work on sea turtles. The
    WPRFMC has been a major supporter and collaborator in this research.

-   [Develop mitigation techniques to reduce mortality of lobster
    bycatch]{.underline}. A successful study was published in 2002 which
    measured handling mortality associated with the Northwestern
    Hawaiian Islands lobster trap fishery. The study found means of
    minimizing mortality induced by handling on board the fishing
    vessel, but also concluded that discarded lobsters are subject to
    high predation from giant trevally which aggregate around the
    fishing vessels, and that total discard mortality might approach
    100%. No feasible method has been developed to allow commercial
    fishers to discard lobster bycatch with a substantial survival rate.
    But the issue has become moot due to changes in harvest strategy.

-   [Develop and evaluate modifications to existing fishing gear to
    allow a reduction in the retention of the legal bycatch of small
    size classes of lobster]{.underline}. Aside from the effective
    lobster trap escape vents developed in the 1980s there has been no
    progress on this issue, largely because of a change in the harvest
    strategy which is now to allow retention of all lobsters (100%
    mortality) and reduce the quota to prevent excessive risk to the
    population. The previous management regimes assumed some survival of
    discarded lobsters but the new strategy does not. Meanwhile the
    issue is moot because the Northwestern Hawaiian Islands lobster trap
    fishery is now closed.

# **Outlook for Fishing Technology Research in the Region**

The crucial problems relate to the closure of fisheries or fishery
sectors to minimize impacts to protected species. To revive these
fisheries will require technological innovations to fishing gear and
tactics. Aside from the problems of policy which tend to make any level
of endangered species interaction unacceptable, there will be a need for
sustained funding to meet this challenge. Many of the fisheries that
have not yet been closed are poorly monitored with respect to bycatch
and interactions with protected species. Funding for more observer
programs and continued funding for the existing observer program will be
needed by the new Central and Western Pacific Region. Existing funding
for sea turtle bycatch reduction of \$3,000,000 annually has been
provided by congressional add-on and will expire after FY 2003 (perhaps
sooner). To meet responsibilities for reduction of bycatch and
endangered species interactions will require a similar level of
permanent base funding for the new Central and Western Pacific Science
Center. Additional funding for albatross and lobster work is being
acquired through funding for cooperative research with industry.

**Fishing Technology Research by the Southeast Fisheries Science
Center**

The Southeast Fisheries Science Center has maintained a fishing
technology capability since the inception of the Pascagoula Exploratory
Laboratory in the early 1950's. This capability has been expanded over
the years to include capabilities in observation equipment (Scuba,
cameras, ROVs, sonars, etc), behavioral research, and staff specialist
in fishing gear design, operation and construction. Research in the
1950s and 1960s was aimed at improving fishing gear and sampling gear
technology. In the 1970's the fishing gear research unit began a program
to address finfish bycatch in the penaied shrimp fishery. In the 1970s
legislation was enacted to protect endangered and threatened sea turtle
species and in the 1980s management plans to recover over fished stocks
had direct impact on the commercial peneaid shrimp trawl fishery in the
Southeastern United States. The shrimp trawl fishery was identified as a
significant source of sea turtle mortality and discards of unwanted fish
bycatch which impacts sustainability of managed fish stocks. To address
these problems, intensive programs were undertaken to develop and
implement sustainable fishing technologies. Research conducted by
federal, state, and industry gear technologist between 1978 and 1988
resulted in the development and refinement of grid devices and webbing
panels to allow escapement of sea turtles, and other bycatch from shrimp
trawls. These devices collectively called turtle excluder devices (TEDs)
were implemented by mandatory regulations into the shrimp industry in
1989. Although there was initially a significant resistance to the
mandatory requirement of this technology, the industry has successfully
implemented and perfected this technology.

The grid and panel devices reduce a significant portion of shrimp trawl
bycatch but do not significantly reduce juvenile fish bycatch of
important commercial fish species, which are under management regimes
including red snapper (*Lutjanus campechanus Poey*), Spanish mackerel
(*Scomberomorus maculates Mitchell*), and weakfish (*Cynoscion regalis
Baloch, Schneider).* These species have been over fished and are under
both state and federal management plans, which include regulations
mandating reduction of shrimp, trawl bycatch mortality. In 1992 a
cooperative research plan was implemented which included the
identification, development, and evaluation of gear options for reducing
fish bycatch in the Gulf of Mexico and Southeastern Atlantic shrimp
fisheries. Between 1990 and 1996 one hundred and forty five bycatch
reduction conceptual gear designs contributed by fishers, net shops,
gear technicians, and biologist were evaluated. Sixteen of these designs
were operationally evaluated on commercial shrimp vessels. Four designs
have demonstrated potential to significantly reduce bycatch of managed
fish species in the Gulf of Mexico and Southeastern Atlantic fisheries.
The fisheye and extended funnel bycatch reduction devices have been
implemented in the Southeastern Atlantic and the Gulf fisheye and
Jones/Davis bycatch reduction devices have been implemented in the Gulf
of Mexico. In 1999, NOAA Fisheries gear specialist from the SEFSC and
Norwegian gear specialist collaborated on a research project
investigating the responses of juvenile fish to water flow patterns in
and around bycatch reduction device designs. This research has resulted
in the documentation of a behavioral response to inclined water flow and
horizontal grids, which has the potential to significantly improve the
performance of bycatch reduction devices for juvenile fish. Research is
ongoing to improve the efficiency of bycatch reduction technology in the
Southeastern penaied shrimp fishery. This technology is also being
transferred to other countries including Australia and Mexico which have
similar fisheries.

In 2001, the NMFS Southeast Fisheries Science Center in cooperation with
the U.S. Pelagic longline fishing industry, the Southwest Fisheries
Science Center, the Northeast Fisheries Science Center, and the
University of Florida began a research effort to investigate the
feasibility of gear modifications and/or fishing practices to reduce the
incidental capture of endangered and threatened sea turtles by pelagic
longline fishing gears. NOAA Fisheries gear specialist are working with
fishers, NOAA researchers from other NMFS regions, and state and
university researchers to gain insight into fishing gear and fishing
practices to develop mitigation measures to reduce turtle interactions
with pelagic longline fishing gear. Prototype mitigation techniques are
being developed using captive reared turtles in controlled experiments
and evaluated on commercial fishing vessels in the Atlantic pelagic
fishing grounds. Studies include evaluation of de-hooker and line cutter
prototypes to allow removal of fishing gear from turtles, bait types and
hook designs developed to reduce hooking of sea turtles, satellite tags
to determine survival, distribution and behavior of sea turtles and
operational changes in fishing practice to reduce turtle interactions.

**Recommendations from 'Managing Bycatch' 1998 -- Accomplishments**

**Southeast Fisheries Recommendations**

-   [Provide stable funding for research and development capabilities in
    gear technology]{.underline}. Funding for research and development
    is dependant on year to year funding through research proposals from
    various sources. Long term base funding is needed to provide stable
    personnel capability and long term commitment to gear technology
    research.

**Atlantic & Gulf Pelagic Fisheries Recommendations**

-   [Improve gear-handling techniques to reduce discard
    mortality]{.underline} The U.S. pelagic fishing industry has
    implemented gear changes and operating procedures to reduce discard
    mortality, but there is no formal program to document the efficiency
    or improve the technology.

-   [Conduct research on gear]{.underline} Research is being conducted
    by the SEFSC on gear modifications and fishing tactics to reduce the
    interaction with and mortality of sea turtles by pelagic longline
    gear. More research effort is needed to address other bycatch
    species in the pelagic longline fishery.

-   [Deployment methods that will reduce interactions between and
    mortality of protected species]{.underline} This research is
    currently being successfully conducted by the SEFSC under a three
    year research program which was initiated in 2001.

-   [Work cooperatively with the fishing industry to transfer new
    knowledge and techniques between fishermen and
    researchers]{.underline} Significant progress has been made recently
    in this area through the cooperative efforts in developing
    mitigation measures for reducing sea turtle interaction with pelagic
    longline gear. Efforts are currently under way to develop a format
    for sharing new technologies and information internationally.

-   [Reduce bycatch and bycatch mortality of undersized swordfish and
    tunas]{.underline} Efforts are underway in this area through time
    and area closures, but there is a need for additional research into
    fishing techniques to reduce the bycatch of undersized swordfish and
    tunas, as well other bycatch species.

**Outlook for Fishing Technology Research in the Region**

There is an increasing need for fishing gear technology research in the
Southeast Fisheries Center and for transfer of existing technology and
expertise to other regions and internationally. The Southeast Fisheries
Science Center has an active fishing gear technology transfer program to
assist domestic and foreign fishers in implementing selective fishing
gears and in developing gear improvements. There has also been an
increased demand for assistance from other regions and agencies to
address fishing gear related problems. Most recently the gear specialist
in the Southeast Fisheries Science Center have assisted the U.S. Navy,
the U.S. Corps of Engineers, the U.S. State Dept., the Australian
fishing industry, the Canadian fishing industry, the domestic catfish
aquaculture industry, and the Northeast Fisheries Science Center in
conducting fishing gear research and development. The Southeast
Fisheries Science Center is currently involved in a cooperative research
program with the pelagic longline fishing industry, the Southwest
Fisheries Science Center, the Northeast Fisheries Science Center, and
the University of Florida to develop mitigation measures to reduce the
interaction and mortality of sea turtle with pelagic longline gear. Work
is ongoing in the Southeast Fisheries Science Center to further improve
turtle excluder device efficiency and to improve bycatch reduction
device efficiency for red snapper in the penaied shrimp trawl fishery.
Gear technologist from the SEFSC are also working with other researchers
on TRT's (take reduction teams) to address marine mammal interactions
with fishing gear.

Critical fishing gear technology R&D issues currently not being
addressed or need additional research are:

-   Undersized swordfish and bluefin, tuna, sharks, and billfish (blue
    and white marlin, spearfish, and sailfish bycatch by the pelagic
    longline fishery

-   Sea turtle interactions with scallop dredges

-   Sea turtle interactions with pot gear

-   Sea turtle interactions with fish trawling gear

-   Discarding and survival of fish in the recreational fisheries

-   Effect of fishing gear on critical habitat

-   Marine mammal interaction with commercial fishing gears

-   Improvement in bycatch reduction in the shrimp trawl fishery

-   Bycatch in fish trawl fisheries

**Needs**

Long term funding for sustained capability in fishing technology
research is needed. Only 40% of salaries and 20% of operations are base
funded. Sixty percent of salaries and 80% of operations are funded
through various sources of funding from annual project proposals. To
meet the expected long term needs in fishing gear technology research,
an annual funding increase of between \$600,000 and \$1,000,000 is
needed.

**Fishing Technology Research by the Northeast Fisheries Science Center
and the Northeast Regional Office**

Fishing technology research has a long history in the northeast. It
began with exploratory fishing and gear research aimed at increasing
catch levels. In the 70's the emphasis changed to conservation
engineering and studies to support management decisions. Some of the
research included investigations of sub-legal escape vents and
degradable links for lobster pots, habitat impacts of hydraulic clam
dredges, and the effects of ghost gill nets. In the early 90's a major
project of the Northeast Regional Office (NERO) was the development and
demonstration of the Nordmore grate for the northern shrimp fishery. The
successful completion of this project significantly reduced the bycatch
of juvenile groundfish in the small mesh trawls.

Fishing technology research in the groundfish fisheries that is directly
conducted by the Northeast Fisheries Science Center (NEFSC) has been
limited in recent years to research related to enhancing stock
assessment data. The NEFSC has performed several studies to assist in
gaining a better understanding of stocks of monkfish, loligo, ilex and
scallops. These studies have been performed in cooperation with the
commercial industry and have been conducted on commercial vessels.

Recent gear research in the regional office has mainly been aimed at
solving the problem of the entanglement of whales and porpoises in
fishing gear.

**Recommendations from 'Managing Bycatch' 1998 - Accomplishments**

-   [Increase the level and broaden the scope of the fishery observer
    program sufficiently to allow qualitative estimates of discards of
    fishery resources and incidental catch of protected species, with
    acceptable levels of precision and accuracy for inclusion in stock
    assessments]{.underline}. Previously the days at sea in the
    groundfish fishery were reduced due to cuts in funding for this
    program. Presently there is an initiative, tied to the amendment 33
    lawsuit that may increase the amount of observer coverage this year
    to 5% and next year 10% of the groundfish trips in the Northeast.
    This initiative is dependent on increased funding for the observer
    program, which has not been approved.

-   [At the discretion of the Regional Administrator, allocate
    additional observer sea-days to evaluate new or existing
    technologies or to certify modifications to existing gear to allow
    fisheries to proceed under the bycatch constraints or potential
    biological removal limits]{.underline}. This has not occurred.
    Previously other agencies have hired their own observers or used
    their own staff to evaluate gear modifications.

-   [Increase the ability to assess the population, ecosystem, social,
    and economic effects of discards, and the impacts of management
    alternatives developed to reduce them through integrated data
    collection and analysis systems]{.underline}. Recently the NEFSC has
    solicited to hire an economist to assist with this work. This effort
    has not received much attention in the past.

-   [Increase research on acute and long-term mortalities of animals
    encountering fishing gears, but not retained. Specifically, evaluate
    the fate of animals that escape through net meshes, the
    hook-and-release mortality of recreational fishes, and the effects
    of bottom-tending mobile fishing gears on benthic
    communities]{.underline}. This effort is being accomplished with
    funding to researchers outside of the NEFSC in the form of grants.
    There are several programs that provide money to researchers for
    conservation engineering work. Personnel from the NEFSC have minimal
    involvement in this work. There has been no effort to assess the
    fate of animals that escape through net meshes in the Northeast and
    only minimal effort at assessing the mortality of recreationally
    caught fish.

-   [Increase regional conservation engineering programs to develop,
    test, and certify species- and size-selective fishing gears to
    address critical conservation programs in the region (e.g.,
    groundfish, scallops, protected species). This program should make
    maximum use of existing expertise in states, universities and the
    industry]{.underline}. This effort is being accomplished with
    funding to researchers outside of the NEFSC in the form of grants.

-   [Develop effective information exchange and distribution programs to
    communicate with the industry, regulators, and general public
    concerning the magnitude of bycatch and efforts to reduce
    it]{.underline}. There are no dedicated staff who work on
    conservation engineering as it relates to the groundfish fishery. We
    do have staff that work on conservation engineering issues that are
    related to protected species.

**Outlook for Fishing Technology Research in the Region**

The NERO realizes the need for investigation of sea turtle bycatch in
many fisheries in the region. The problems are being worked on
cooperatively with the southeast region and with various states. More
research effort is needed for this and other protected resource
problems.

The NEFSC has no dedicated personnel who work on conservation
engineering issues in the groundfish fisheries. Presently all the
research is being conducted by State agencies or private organizations.
A recognized problem in the Northeast is the lack of direction of the
research. There appears to be a haphazard approach to funding
conservation-engineering projects. With the addition of conservation
engineering staff dedicated to conservation engineering issues in the
Northeast, the NEFSC could have better control and focus in the funding
priorities related to gear research.

**Needs**

Presently the NMFS in the Northeast Region has no personnel dedicated to
bycatch research, fishing technology research, or selectivity research
with the exception of research being conducted to reduce the bycatch of
marine mammals. The Northeast region is an area where other researchers
outside of NMFS have traditionally conducted studies that address these
topics, yet with little direction from NMFS. The Northeast region should
look at developing a group of NMFS employees that direct and oversee
gear research in this region. This group would be tasked with
establishing research priorities, reviewing the credibility of the
research being conducted, and bringing the research to fisheries
managers. With adequate funding, this group could also perform
cooperative research with the fishing industry that addresses research
needs in the region.

**Review of New England groundfish fishery bycatch issues**

**Introduction**

The NFTWG invited researchers from state, university, and private
organizations working on gear related projects in the Northeast region
to present the results of their research and to provide comments and
recommendations to the group on the New England groundfish bycatch
problem. John Watson discussed the purpose, organization, and objectives
of the NFTWG and explained the objectives of the meeting to the invited
scientist. A general discussion followed which included clarification of
the purpose and intent of the NFTWG. Discussion followed on the
definition of bycatch and Ron Smolowitz suggested that NMFS clearly
define bycatch in terms of fisheries interactions. Some definitions are
inclusive of interactions with fishing gear that does not result in
capture. Henry Milliken then gave a brief review of the New England
groundfish fishery to the group and invited scientist.

Arne Carr, Massachusetts Division of Marine Fisheries gave a
presentation on two experimental trawls designed to reduce the bycatch
of cod in the yellowtail and winter flounder fishery and experimental
designs to reduce bycatch of scup in the loligo fishery. He also
presented results of evaluations of low cod bycatch gillnet designs. The
results of these evaluations are presented in Appendix II.

Cliff Goudey, MIT Sea Grant College Program, gave a presentation on
novel methods of reducing trawl bycatch (Appendix II). Cliff presented
information on traditional techniques for reducing bycatch including
exploiting size and shape differences and behavioral differences in
target and bycatch species. He discussed re-defining bycatch (zero
discard fisheries) and using the concept of dynamic management to direct
effort in areas of high target/bycatch ratios. He presented information
on the use of kites and fabric panels to manipulate and control trawl
webbing configurations and the application of these techniques in
developing gear modification techniques for reducing bycatch. Cliff also
discussed the possibility of using stretch mesh sections with the trawl
extension to improve selectivity of trawls, soft door designs, the
application of groundfish pots, and bycatch problem areas for the
Northeast groundfish fishery.

### Joe DeAlteris, University of Rhode Island, gave a presentation on size selection in 

### bottom trawls (Appendix II). The purpose of his presentation was to address what we 

### know about size selection in bottom trawls for flatfish and what information is needed. 

### He presented an excellent summary of size selectivity theory and presented data from 

### several past and recent size selectivity studies. Analysis of data from these studies 

### indicate that the selection factor (S.F.) appears to vary with fish size due to 

### morphological changes in the ratio of fish girth to length. S.F also appears to vary with 

### region due to differences in fish morphology based on feeding and spawning condition. 

### He recommends that, scientist should determine S.F. with an error estimate so that they 

### can statistically compare S.F.s from experiments with different mesh sizes and different

### regions.

# Pingguo He, University of New Hampshire Sea Grant, gave a presentation on the development of a double grid system to reduce cod catch in flatfish trawls, research on a semi pelagic shrimp trawl, cod and flatfish separators using horizontal panels, and shallow gillnets. 

# 

# Chris Glass, Manomet, gave a presentation on research being conducted on square mesh windows, behaviour of cod, selection curves by season, composite codends for reduction of bycatch and regulatory discards of cod, a grid system for reduction of cod bycatch and evaluations of hexagonal mesh for bycatch reduction. 

Ron Smolowitz, Coonamessett Farm, presented the results of research on
reducing the bycatch of groundfish in the scallop dredge fishery.
(Appendix II).

Following the presentations by invited scientist the New England
groundfish bycatch problem was discussed by the attendees and
recommendations proffered. Attendees felt that significant progress is
being made to address the New England bycatch problem, but that there
are significant obstacles that are inhibiting the development of
effective gear related solutions. Among the most significant obstacles
expressed by all the participants in the workshop was the administrative
burden involved in conducting required research. The permitting
requirements for conducting fishing gear experiments was the single most
restrictive burden identified. The participants made a very strong
recommendation that the Sustainable Fisheries Act (SFA) be changed to
ease the issuance of experimental permits. Legitimate research needs to
be exempted from guidelines of SFA. One possible solution would be to
allow commercial vessels to qualify as research platforms. Participants
also expressed frustration with inconsistencies in the permitting
process between applications.

There is also a problem in using commercial vessels for gear development
research that are under regulatory restrictions limiting days at sea
(DAS). Days at sea conducting experimental gear research should not be
counted against the vessel quotas. DAS have been reduced to the point
that no time is available for research from commercial vessels. Some
participants stated that research in state waters is being held hostage
by the National Marine Fisheries Service regional offices and that the
responsibility for research in state waters should be placed with the
state.

The participants expressed frustration over the subject of
enforceability of regulations involving gear modifications to reduce
bycatch. Fishery managers are using inability to enforce regulations as
an "excuse" not to implement gear based techniques to reduce bycatch.

Participants also identified the problem of research results not being
conveyed to management. There is an apparent disconnect between the
researchers and the councils. It was felt that the NMFS Fishing
Technology Working Group was a good start at addressing the national
problem, but that there should also be a mechanism in each region to
convey the results of research to the fishery management councils. The
participants suggested that regional conservation engineering
organizations should be formed to convey scientific findings to the
councils. Another suggestion offered was the councils form gear
technology committees. Plan development teams need to include personnel
with gear expertise.

The participants also expressed concern that NMFS is not publicising the
success of fishing technology research in addressing bycatch problems.

Other recommendations from the participants included:

-   More industry bycatch data collection initiatives

-   More "port meetings" to canvas industry on research needs

-   More observer coverage

-   Non catch mortality should not be included as bycatch

-   More communication between regions to share expertise

-   More personnel with gear expertise on committees

-   NMFS needs to make a sustained commitment to gear technology
    research

-   More support for responsible fishing programs (examples; FAO and DFO
    programs)

# 

##  

**APPENDIX I. National Fishing Technology Working Group Terms of
Reference**

**NMFS National Working Group on Fishing Technology**

**Agency Needs**

Effective management and conservation of U.S. fishery resources requires
protection of critical habitat and development of selective harvesting
gear. Increasing demands on fishery resources and interaction of fishing
gear with protected species requires the development of new innovative
harvesting technology which minimizes environmental impacts and
associated bycatch. Within NMFS, fishing technology research has been
successful in developing innovative gear designs to mitigate impacts of
fishing gear and maintain viable commercial and recreational fisheries.
This research has generally been specific to different regions within
the United States and in most cases has involved cooperative research
with other agencies, countries, universities, and industry. The NMFS
Science Advisory Board recognizes a need to promote better communication
between the different science centers and regions within the NMFS and to
focus fishing technology research on a national level. To meet this need
the NMFS Science Advisory Board has recommended the establishment of the
Fishing Technology Working Group.

**Mission**

Promote the development and use of innovative technologies and
methodologies to reduce the impact of harvesting and recreational
fishing gear on critical habitats and improve selectivity of fishing
gear by reducing bycatch and interaction with protected species.

Foster communication and collaboration regarding fishing technology
research and the development of new technologies and appropriate
application of existing technologies within NMFS and between NMFS and
its partners.

**Composition**

-   One or more scientist from each of the five NMFS Science Centers
    and/or regions.

-   One representative from NMFS Headquarters.

-   Other participants which may be nominated by the Science Board.

-   Experts from other government offices, universities, and the private
    sector to be invited on an ad hoc basis.

-   Subcommittees will be established as necessary to address specific
    areas of interest and report back to the working group.

**Responsibilities**

1)  **Identify critical needs for fishing technology research and
    provide research and development leadership by:**

-   Identifying and examining current and past research efforts
    including related efforts within other agencies, industry and
    international organizations.

-   Identifying and prioritizing fishing technology research needs
    through cooperation with fishery managers and other fishing
    technology scientist.

    -   Monitoring NMFS research activities which involve fishing
        technology.

    -   Identifying requirements of technical assistance and training
        related to application of new technologies.

    -   Preparing recommendations on how fishing technologies can be
        modified, expanded, and/or improved to support agency
        stewardship responsibilities.

    -   Sponsoring, encouraging, and participating in fishing technology
        research and development.

1)  **Identify costs and funding opportunities for technological
    innovation by:**

-   Evaluating the costs and benefits of developing and/or applying new
    research technologies.

-   Developing appropriate budget initiatives

-   Assisting in the development of new funding opportunities in
    collaboration with other organizations.

2)  **Improve awareness of agency needs for fishing technology research
    by:**

-   Preparing and delivering and annual briefing to the NMFS Science
    Board apprizing it of fishing technology developments and needs and
    opportunities for collaboration and/or budget initiative
    development.

-   Provide data and information for presentations, briefings, and
    talking points for agency management and Congress.

3)  **Provide information and consultation on fishing technology
    issues.**

# 

# 

# 

# 

# **APPENDIX II. Presentations on Gear Research Project in the Northeastern United States**

# **Reducing the bycatch of the sacred cod**

# **Two Experimental Trawls**

**Arne Carr**

Massachusetts Division of Marine Fisheries

-   Ribas trawl

-   Topless Trawl

# 

# Catch rates and analysis of cod, yellowtail flounder, and winter flounder catches

# 

# 

# ![](media/image1.wmf)

# 

# Reducing the bycatch of Scup

# 2001 Trawl Design

-   Raised footrope

-   Fish eyes with separation panels

### 

### Issues\...

-   Bycatch in the squid fishery

-   Access to closed areas

-   Offshore / inshore vessels and gear

####### 2002 Funding through scup/squid set-aside

#  

# Summer 2001 Results

#  

# ![](media/image2.wmf)

# 

# October 2001 Results

# ![](media/image3.wmf)

### 

### 

### Testing of Low Cod-Bycatch Gillnets:

### Two Experimental Nets

•Dual Leadline: Usual floatline is replaced by another leadline

•Foamcore plus lead: Foamcore floatline with lead added every 30 ft

# 

# 

# Results so far\...

![](media/image4.wmf)

# 

### Now what?

## Ten more hauls just completed.

## Exp. Nets provide advantages: lower harbor porpoise bycatch?

## No floats = fewer large cod

#  

# 

#  **Novel methods of reducing trawl bycatch**

## **Clifford A. Goudey** 

## Center for Fisheries Engineering Research

## MIT Sea Grant College Program

## 

### Traditional options using trawl gear design

## **Exploit size/shape differences**

### **Mesh size**

### **Grates**

## **Exploit behavioral differences**

### **Large mesh panels**

### **BRDs (bycatch reduction devices\_)**

### **Separator panels (dual codends)**

# 

# 

# 

# 

### Other ways of controlling bycatch

# 

•**Re-definition -** it's not bycatch if it is landed and sold - ***zero
discard fisheries***.

•**Dynamic management -** direct fishing effort to areas with high
target/bycatch ratio.

**These approaches require a major shift in assessment/management
methods**

### Controlling trawl position and shape using fabric panels

•First used in U.S. in 1987 where a headrope kite was used to gain
headrope height and lift the footrope well clear of bottom. Result was a
low-horsepower squid-butterfish net that fished effectively while
reducing bycatch (Goudey, 1987).

•**Current research thrust -** Use of fabric panels to reduce habitat
threats of trawl gear

# 

### Why fabric devices?

### 

•Unlike netting, solid panels can generate lift.

•Forces are proportional to V2, therefore shape is independent of speed.

•Distributed devices reduce the need for hard-spot reinforcements and
abrupt shape changes.

•Lightweight, low cost.

•No depth restrictions.

•Can be rolled on net drum.

# 

# 

**Sweep kites** - reaching bottom without weight

# 

Triangular mesh kites for local lift and spread

Can such devices influence fish behavior?

Ribbon foil kites provide height and width to trawl body. This may alter
perception by fish regarding trawl narrowing and escape opportunities.

Circular ribbon foil kites add diameter without requiring a rigid hoop

Can prevent mesh collapse in codends and extensions

### Soft Trawl Doors

May offer a practical method of spreading a net without the use of
bridles and groundwires.

Potential application in Shrimp and other non- herding species.

# 

# 

### Stretch mesh catch controls

•Project idea from Nino Randazzo of Gloucester who was tired of dumping
large hauls of cod. He sought a method that would increase extension
mesh size once a certain amount of fish was in the codend.

•NEC provided development funds to try a stretch mesh extension
constructed of bungee twine.

# 

Stretch-Mesh provides regulation mesh size at the beginning of the tow.

Stretch-Mesh expands to increase escapement under a specified load.

Controlling bycatch using gear modifications may be counterproductive
under the SFA due concerns over habitat impacts. The development of
trawls that are species selective, even if possible, will result in
unacceptable habitat risks.

A preferred method may be to focus on mesh size while carefully
controlling small-mesh fisheries through area controls and using simple
gear restrictions

### Groundfish pots

### 

•Size and species selective.

• High survival of discards.

• Habitat friendly.

### 

### Bycatch problem areas for NE groundfish

•Certifying small-mesh fisheries as groundfish rebuild.

• Quantifying groundfish bycatch in midwater fisheries operating in
closed areas.

• Understanding catch and bycatch implications of latent permits (we
need a better understanding of fishing power).

• Appropriate gear for re-activating permits (understanding the bycatch
implications of passive methods).

# 

# 

# **Size Selection in Bottom Trawls Harvesting Flatfish in Southern New England**

## **Joseph T. DeAlteris and Laura Skrobe**

## ** **University of Rhode Island Kingston, RI

# 

### Presentation Outline

Purpose

Theory, Application, and Goal of Size Selection

Previous Work

Recent Field Studies of Analyses

Conclusions and Need for Future Studies

Purpose of this Presentation

Address the question: given what we know about size selection in bottom
trawls for flatfish what more do we need to know and why?

### 

### Theory of Fish Size Selection in Bottom Trawls

For a given codend mesh size and shape; and a particular fish species

## 

### Application of Fish Size Selection in Bottom Trawls

If *L*~50~ of size selection curve matches minimum legal fish size

## 

## Goal of Fish Size Selection in Bottom Trawls

A. To control fish age or size of entry into fishery, so as to maximize
yield per recruit.

## =

### Goal of Fish Size Selection in Bottom Trawls

B. To control fish age or size of entry into fishery, so as to maximize
spawning stock biomass per recruit

## 

### Additional Theory of Fish Size Selectivity in Bottom Trawls

A.  Extrapolate the results of a given mesh size and shape selectivity
    study to other mesh sizes of the same shape using selection factor
    (*SF*)

Assume ratio of fish girth to fish length is constant

### Additional Theory of Fish Size Selectivity in Bottom Trawls

• B. Logistic cumulative distribution function (LCDF) is the model used
to fit observed probability of retention values from an experiment

$$\text{PL}_{L} = \left( 1 + e^{\left( - \alpha 2 \ast \left( L - L_{\text{50}} \right) \right)} \right)^{- 1}$$

Where: *PLL* is the probability of retention at length (*L*)

*α*2 is the steepness of the curve, and

*L50* is the length at 50% selection.

### Additional Theory of Fish Size Selectivity in Bottom Trawls

•Therefore, based on *SF* and *a*2 estimated from previous size
selection experiments, can predict a family of selectivity curves for
other mesh sizes.

### Previous Work

DeAlteris, J.T. and Grogan, C. 1997. An analysis of harvesting gear size
selectivity for eight demersal groundfish species in the Northwest
Atlantic Ocean. URI Fisheries. Tech Report No.1

## 

### ![](media/image5.wmf)Winter Flounder Diamond Mesh

### Summer Flounder Diamond Mesh

![](media/image6.wmf)

### ![](media/image7.wmf)Yellowtail Flounder Diamond Mesh

### Winter Flounder Square Mesh

![](media/image8.wmf)

### Yellowtail Flounder Square Mesh

![](media/image9.wmf)

Summary of Previous Studies

![](media/image10.wmf)

### Results of Recent Studies on Larger Mesh

  ------------------------- --------------------- ------------ ------------
  Mesh Shape                Species               SF            

  Diamond                   Winter Flounder       2.51         0.68

                            Summer Flounder       2.70         0.48

  Square                    Winter Flounder       2.22         0.40

                            Summer Flounder       2.49         0.46
  ------------------------- --------------------- ------------ ------------

### Results of Recent Studies on Larger Mesh

  ------------------------- --------------------- ------------ ------------
  Mesh Shape                Species               SF            

  Diamond                   Winter Flounder       2.30         0.42

                            Yellowtail Flounder   2.52         0.73

  Square                    Winter Flounder       2.22         0.40

                            Yellowtail Flounder   2.13         0.98
  ------------------------- --------------------- ------------ ------------

### 

### Results of Recent Studies on Larger Mesh

Skrobe, Beutel, and DeAlteris (2001) --

RI: 15.2, 16.5, and 17.8 cm mesh

![](media/image11.wmf)

### 

### Comparison of S.F. Results of Previous and Recent Studies

  ------------------------- --------------------- ------------ ------------
  Species                   Shape                 Previous     Recent

  Yellowtail Flounder       Diamond               2.35         2.42

                            Square                \-           2.08
  ------------------------- --------------------- ------------ ------------

### Comparison of S.F. Results of Previous and Recent Studies

  ------------------- ---------------- ---------- ----------- ------------
  Species             Shape            Previous   Recent (RI) Recent (MA)

  Winter Flounder     Diamond          2.15       2.5         2.3

                      Square           1.92       2.2         2.2
  ------------------- ---------------- ---------- ----------- ------------

### Comparison of S.F. Results of Previous and Recent Studies

### 

  ------------------- ---------------- ---------- ----------- ------------
  Species             Shape            Previous   Recent (RI) Recent (MA)

  Summer Flounder     Diamond          2.46       2.7         2.5

                      Square           \-         2.5         2.1
  ------------------- ---------------- ---------- ----------- ------------

### 

### Conclusions

-   S.F. appears to vary with fish size due to morphological changes in
    the ratio of fish girth to length

-   S.F. appears to vary with region due to differences in fish
    morphology based on feeding and spawning condition

-   Therefore, we should determine S.F. with an error estimate so that
    we can statistically compare S.F.s from experiments with different
    mesh sizes and different regions

## 

## 

### S.F. Error Analysis

### Management Application of Fish Size Selection in Bottom Trawls

+/- 0.1 error in S.F. results in +/- 1.8 cm error in *L*~50~

Small errors in S.F. can result in substantial losses of legal fish to
fishermen, or discards and waste of resource

Therefore, should collect new data for each mesh size, so as to assure
resource managers and fishermen of agreement between mesh selection
characteristics and minimum legal fish size

## 

# 

#  **Double Grid System to Reduce Cod Catch in Flatfish Trawls**

# **Bycatch and Discard**

**Pingguo He**

University of New Hampshire Sea Grant

Work in Progress:

Double Grid Device to Reduce Cod Bycatch in Flatfish Trawls

Exploiting differences in behaviour of flatfish and cod inside a trawl
net, a double grid selectivity device was designed and refined through
flume tank testing. A short sea trial was carried out in the fall of
2001 on board a commercial fishing vessel in the Gulf of Maine. Results
are very preliminary. Further sea trials are being carried out in the
spring of 2002, and more planned for the fall of 2002 and spring/summer
of 2003. Other projects being carried out in the University of New
Hampshire related to fisheries conservation engineering include
modification of gear to reduce seabed contact, and shallower flatfish
gillnets to reduce cod bycatch.

# 

# 

Bycatch Reduction in Gulf of Maine Groundfish Fisheries

**Christopher Glass**

Manomet Center for Conservation Sciences

81 Stagepoint Road

Manomet MA 02345

Manomet Center for Conservation Sciences is currently conducting a
number of studies aimed at understanding the nature and extent of
discarding in Gulf of Maine groundfish fisheries, and exploring
innovative and novel approaches to mitigate bycatch and discard. In
particular, we are investigating the effect of mesh size, mesh type,
composite mesh codends and articulating excluder grids. All of the
research is based on the philosophy championed by Clem Wardle of The
Marine Laboratory Aberdeen, that is, an understanding of the natural
behavior patterns and reaction behaviors of fish is the only logical
entry point into the study and development of more selective fishing
gears. To that end all of the studies outlined below has a major
component of underwater videography aimed at understanding the reaction
behavior of target and non-target fish. The approach is to identify
species or size specific behavior patterns and to attempt to use this
information to target only those fish which we want to catch and release
all other fish underwater.

# Square-mesh extension window 

Scup is an important commercial and recreational species in Mid-Atlantic
and southern New England waters. A recent study by Manomet Center for
Conservation Sciences confirmed scup as one of the main constituents of
the discard in small mesh fisheries targeting squid, by assessing its
rate of discard in the 1997 fishing season at 5 % of total weight
landed. Manomet Center for Conservation Sciences (MCCS) and The
Massachusetts Division of Marine Fisheries (MAMF) has shown that
*Loligo* squid demonstrate specific behavior patterns when herded into
towed trawl gear in the shallow inshore waters of Nantucket Sound. These
specific behavior patterns allow squid to be separated from other
important bycatch species such as scup and flatfish. Here we focus on
squid fisheries in the Mid-Atlantic region, where bycatch and discard of
scup in directed small mesh fisheries, has been identified as a high
priority by the Mid-Atlantic Fisheries Management Council. NMFS imposed
Gear Restricted Areas to restrict small-mesh fisheries as a way of
reducing discard mortality for small scup. Our aim here is to use
conservation engineering techniques to identify means of reducing
inadvertent capture of undersized scup in small fisheries as a means of
providing alternative management strategies to GRA's.

The specific objectives of this program of research were:

1.  To determine what gear modifications can be made to reduce the catch
    of scup in small mesh nets;

2.  To test the effectiveness of novel codend configurations (designed
    with input from fishing industry groups), against standard codend
    arrangements;

3.  To develop modified fishing gear and/or fishing practices that
    reduce levels of bycatch and discard of undersized scup;

Four different designs were tested;

1.  4 ½ " diamond mesh window

2.  5 ½" square mesh window

3.  5 ½" square mesh window with a black tunnel

4.  5" diamond mesh extension window

Experiments 1. and 4. showed no decrease in bycatch of undersized scup.
Experiment 2. showed a decrease in discard of scup by nearly 60% while
the inclusion of the black tunnel proved insignificant in improving the
effectiveness of the 5 ½" square mesh window.

The most obvious conclusion from this research is that nets **can** be
redesigned in a simple way to reduce the bycatch and discard of scup.
Inclusion of a 5 ½" square mesh extension section shows significant
reduction in capture of undersized scup. In addition, there was no
significant reduction in squid catch.

# Composite and hexagonal mesh codends

Traditional codends comprised of either square or diamond mesh have
increasingly been demonstrated to be ineffective in releasing all
undersized individuals particularly in mixed or multi-species fisheries.
Square mesh codends are more effective at releasing roundfish while
diamond mesh codends are more effective at releasing flatfish. Other
countries, notably Denmark, Sweden, The United Kingdom and Ireland have
introduced composite mesh codends (that is codends composed of a
combination of mesh sizes and or configurations) into their fisheries
management regulations to improve the selective efficiency of the
codend. Manomet, Center for Conservation Sciences, The Massachusetts
Division of Marine Fisheries and The Department of Marine Resources,
Maine, have conducted preliminary trials with composite codend
configurations and hexagonal mesh codends in the Gulf of Maine during
1998/2001.

At time of writing these studies are not complete but preliminary
analysis indicates that a composite codend constructed with 6 ½" square
mesh on the top panel and 6 ½" diamond mesh on the bottom panel reduces
capture of undersized cod by almost 70% while not reducing catch of
legal sized cod or flatfish. This configuration is showing tremendous
potential and is the subject of further detailed investigation.

Conclusions

-   Codend modifications can help reduce bycatch and discard of
    undersized fish

-   Composite mesh codends significantly reduce bycatch and discard of
    cod -- mainly by increasing L50

-   Seasonality is an issue. Selectivity of codends is different at
    different times of year. This could be a significant problem for
    management plans.

-   6 in. Hex mesh appears to be very effective in reducing cod bycatch
    and discard although results are as yet preliminary.

***Cod excluder device (Ex-It)***

During the period immediately following the collapse of cod stocks in
Iceland, innovative solutions were sought to help reduce cod bycatch. A
bycatch reduction device called Ex-It was developed by Icelandic
industry, science and Governmental collaboration. This device is now
utilized on over 60% of the fishing fleet in Icelandic waters and has
been demonstrated to effectively reduce the bycatch of undersized fish
in fisheries from Iceland to Namibia. Manomet Center for Conservation
Sciences, MaDMF, Maine DMR and DFO Canada have conducted studies on the
effectiveness of this cod excluder grid in the waters of the northwest
Atlantic during 2000 -- 2002. Studies were conducted initially with a
bar spacing of 60 mm although future studies will focus on bar spacings
of 50mm, 60mm and 70mm. Work is ongoing but preliminary analysis shows
dramatic reduction in bycatch of cod with the 60mm grid. However, there
is also a noticeable reduction in catch of legal sized flatfish.

Conclusions

-   Ex-It grid significantly reduces bycatch and discard of cod

-   Also reduces catch of flatfish which may prove unacceptable to
    industry

-   Results are comparable to Icelandic studies

-   A new design with a lower guiding panel may be more effective and
    will be tested in 2002

# **Dredge Modifications to Reduce Incidental Groundfish Catches In the Northwest Atlantic Sea Scallop Fishery**

**Ron Smolowitz**

Coonamessett Farm

### Background

-   1994: 50,000 scallop DAS

-   2001: 25,000 scallop DAS

-   Bycatch quantities unknown

-   Bycatch species primarily flatfish, skates, and monkfish

-   Gadoids are seldom caught

# 

### The Gear

-   Vessels tow two 15-foot wide dredges

-   Dredge frames weigh about 2500 lbs

-   Bag constructed of 3.5-inch rings

-   Twine top used to lighten the bag

-   In 1994 twine top was 6-inch mesh

-   Dredges are rigged with chains

### 

### 

### Bycatch Reduction Ideas

-   Windows in the twine top (rope back)

-   Tickler chains on the bale

-   Block between cutting bar and depressor

-   Reduce towing speed

-   Stop before hauling

-   Noise makers

### Twine Top Experiments 1996-7

-   10-inch diamond to 6-inch diamond (50 Tows)

-   8-inch square to 6-inch diamond (80 Tows)

### Results of Twine Top Tests

## Scallops

### No reduction with 8-inch twine top

### Significant reductions with 10-inch twine top

#### 35% reduction of scallops \> 90 mm

#### 52% reduction of scallops \< 90 mm

#### 

## YT Flounder 8.7-24.6 fish/hr

### 31-38% reduction with 8-inch twine top

### 37-67% reduction with 10-inch twine top

### 

### 

### Results of Twine Top Tests

## Skate 37.6-184.2 skate/hr

### 16-23% reduction with 10-inch twine top

### 26-70% reduction with 8-inch twine top

### 

## Monkfish

### Indications of some reduction with 10-inch

### Speed Trial July 1999

-   5 knots vs 3 knots covering same ground

-   16 tow pairs

-   Scallops: 2991 vs 992

-   Skates: 163 vs 43

-   Monks: 28 vs 29

-   Flatfish: 125 vs 27

-   Others: 31 vs 1

# 

### 

### Hanging Ratio July 1999

## 10-inch twine top hanging ratio 1:1 vs 2:1

## 8 tow pairs

## 

## Scallops: 10232 vs 10702

## Skates: 268 vs 327 22% reduction

## Monks: 81 vs 82

## Flatfish: 171 vs 230 35% reduction

## Other: 51 vs 88

### Raked Dredge Oct 1999

## Raked dredge w/10-inch excluder panel vs 10-inch twine top

## 5 tow pairs

## 

## Scallops: 23.5 bu vs 24 bu

## YT flounder: 82 lbs vs 174 lbs

## Skates: 6.5 bu vs 10 bu

### Raked Dredge May 2000

## Raked dredge w/8-inch excluder panel vs 10-inch twine top

## 12 tow pairs

## 

## Scallops: 95 vs 105 bu 10% reduction

## YT flounder: 327 vs 530 39% reduction

## Skates: 434 vs 578 25% reduction

### 

### Raked Dredge May 2000

## Raked dredge w/extra blocking vs 10-inch twine top

## 21 tow pairs

## 

## Scallops: 135 vs 149 bu 9% reduction

## YT flounder: 442 vs 770 43% reduction

## Skates: 1236 vs 1769 30% reduction

### Excluder Panel May 2000

## 8-inch excluder panel vs 10-inch twine top

## 11 tow pairs

## 

## Scallops: 53 bu vs 56 bu

## YT flounders: 236 vs 250

## Skates: 993 vs 1252 22% reduction

### Fish Sweep May 2000

## Fish sweep w/8-inch excluder panel vs 10-inch twine top

## 14 tow pairs

## 

## Scallops: 35 vs 63 bu 42% reduction

## YT flounder: 73 vs 348 79% reduction

## Skates: 138 vs 202 30% reduction

# 

### 

### New Dredge Design

## Bale extends straight out 18 inches before tapering to tow point

## Distance from cutting bar to tow point remains the same

## Dredge is lightened by removing gussets and other reinforcing components

### About 500 lbs lighter (new frame is 1900 lbs)

# 

### New Dredge Dec 2000

## New dredge w/fish sweep vs standard dredge w/10-inch twine top

## 16 tow pairs NLSA

## 

## Scallops: 461 vs 414 bu 11% increase

## YT flounder: 99 vs 160 37% reduction

## Skates: 316 vs 440 29% reduction

## Other flats: 101 vs 134 26% reduction

## Monks: 33 vs 30

### New Dredge January 2001

-   New dredge w/fish sweep vs standard dredge w/10-inch twine top

-   25 tow pairs CAI

-   Scallops: 680 vs 576 bu 22% increase

-   YT flounder: 26 vs 44 41% reduction

-   Skates: 772 vs 879 15% reduction

-   Other flats: 90 vs 127 40% reduction

-   Monks: 96 vs 60 58-80% increase

### New Dredge October 2001

-   New dredge w/fish sweep and excluder rings vs new dredge w/10-inch
    twine top

-   27 tow pairs CAI

-   Scallops: 481 vs 495 bu

-   YT flounder: 337 vs 551 40% reduction

-   Skates: 2002 vs 3359 40% reduction

-   Winter flounder: 206 vs 394 48% reduction

-   Monks: 584 vs 605

### Gear Research Needs

## 10-inch vs 6-inch twine tops on standard dredge frames in high scallop concentrations

-   New dredge w/fish sweep and excluder rings vs standard dredge
    w/6-inch twine top