Table of Contents

• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Parameters
• Instruments
• Deployments
• Project Information
• Program Information
• Funding

Project Leader: Shelly Tallack, Gulf of Maine Research Institute

The purpose of this project was to test an array of fishing gear fitted with and without non-magnetic rare earth metal (lanthanide/cerium) to test the aversion by spiny dogfish to baited fishing gear as a means of reducing the catch of dogfish during time when dogfish abundance is problematic for fishermen. This study addresses the NEC research topics of: fishing gear selectivity and fish habitats and ecology. This study employed fishery-independent sampling techniques, and involved a team of approximately two fishermen and two scientists. Overall, there is little evidence to suggest that mischmetal has the potential to reduce the catch of dogfish in either commercial or recreational gear types in the Gulf of Maine.

In total, six dogfish research trips were undertaken, during August and September of 2007. The
commercial lobster vessel, FV Survivor (13 m), was utilized as the research platform, which afforded
extensive deck space and winch gear for efficient operation of the longline and jig gear.

To prepare for deployment on fishing gear, industry standard trapezoidal mischmetal ingots (HEFA
Rare Earth Canada Ltd., Richmond, BC, Canada) measuring ~45 mm x ~45 mm x ~45 mm x ~130 mm
were sliced into pieces measuring ~45 mm on each side, by ~5 mm thickness. For attachment to
fishing gear, ~2 mm holes were drilled at ~5 mm up from the bottom edge and ~5 mm down from
the top corner of each mischmetal slice; the slices were then attached to jigging gear using 2 mm zip
ties, and to the longline gear by threading the twine leaders through the drilled holes. On both
jigging gear and longline gear, the mischmetal was secured ~10 cm up from the hook and bait.

A total of four (100 hook) longlines were built, each consisting of 50 control hooks (just hook and
bait) and 50 treatment hooks (hook, bait and mischmetal). The hooks were arranged along the
longline in alternating groups of 10 (i.e. 10 control, 10 treatment, etc.)as a means of efficiently
verifying that equal numbers of treatment and control hooks were attached to each longline; this
approach also enabled effective gear maintenance in the field where deck space is limited. Four
longlines with 100 hooks were set on trips 1-3; at this time one longline was lost overboard. On trips
4-6, three longlines were set, two with 100 hooks each and one with 140 hooks. The additional
hooks were added to make up for the lost longline, but mischmetal availability limited this increase
to 40 hooks. In total, during six sampling days 21 longlines were set, totaling 2080 hooks (50%
control and 50% treatment). All longlines were set at similar depths on each day (~60-100 m), in
close proximity to one another to ensure similar fishing conditions between each set. Soak times
ranged from 1-2 hours.

Jigging using rod and reel took place on each of the six vessel days, to test the effectiveness of
mischmetal at deterring dogfish from recreational hook gear. Jigging was undertaken during the
soak-time for each longline. Each rod and reel (n=3) was set up with two hooks (2-4 hooks is typical
while fishing for groundfish), with one treatment and one control hook; 73 jig-lines were set,
comprising a total of 146 baited hooks (50% control (C) and 50% treatment (T)).

All animals caught by both jig and longline gear were noted for: hook type (i.e. treatment or
control), bait presence, species, size (total length, TL) and sex where possible. The catch was then
released.

In addition, wire lobster gear was deployed on two days. Two strings were set for 24 hour soak
times, each string comprising 16 traps in total. Control (n=8) and treatment (n=8) traps were
alternated along each string. All traps were baited, and the treatment traps had three pieces of
mischmetal attached around the trap entries. The total catch was counted and quantified by
species; only fish species were measured, and where possible, such as in the case with
elasmobranchs, sexed. (from final report)

In situ video footage was obtained through collaboration with the University of New Hampshire's
Atlantic Marine Aquaculture Center (Durham, NH).

Data analysis:
Data analysis was undertaken by GMRI from October 2007 onwards. Analyses were performed using
a combination of SPSS 15.0 software (SPSS, Inc, Chicago, IL), MATLAB (The MathWorks, Inc., Natick,
MA) and Grapher 6 (Golden Software, Inc., Golden, CO). The categorical frequency data recorded for
dogfish caught by control versus mischmetal hooks was analyzed using Chi-square analysis.

The Northeast Consortium encourages and funds cooperative research and monitoring projects in the Gulf of Maine and Georges Bank that have effective, equal partnerships among fishermen, scientists, educators, and marine resource managers.

Priority areas for Northeast Consortium funding include selective fishing-gear research and development. The development of selective fishing gears that enhance gear selectivity, target healthy stocks, reduce bycatch and discard, reduce or eliminate technical barriers to trade, minimize harvest losses, and improve fishing practices. Studies of new and developing fishing gears and technologies aimed at reducing environmental impact is funded under Project Development.

At the 2008 Maine Fisheremen's Forum, the Northeast Consortium organized a session on data collection and availability. Participants included several key organizations in the Gulf of Maine area, sharing what data are out there and how you can find them. 

The Northeast Consortium has joined the Gulf of Maine Ocean Data Partnership. The purpose of the GoMODP is to promote and coordinate the sharing, linking, electronic dissemination, and use of data on the Gulf of Maine region.

The Northeast Consortium was created in 1999 to encourage and fund effective, equal partnerships among commercial fishermen, scientists, and other stakeholders to engage in cooperative research and monitoring projects in the Gulf of Maine and Georges Bank. The Northeast Consortium consists of four research institutions (University of New Hampshire, University of Maine, Massachusetts Institute of Technology, and Woods Hole Oceanographic Institution), which are working together to foster this initiative.

The Northeast Consortium administers nearly $5M annually from the National Oceanic and Atmospheric Administration for cooperative research on a broad range of topics including gear selectivity, fish habitat, stock assessments, and socioeconomics. The funding is appropriated to the National Marine Fisheries Service and administered by the University of New Hampshire on behalf of the Northeast Consortium. Funds are distributed through an annual open competition, which is announced via a Request for Proposals (RFP). All projects must involve partnership between commercial fishermen and scientists.

The Northeast Consortium seeks to fund projects that will be conducted in a responsible manner. Cooperative research projects should be designed to minimize any negative impacts to ecosystems or marine organisms, and be consistent with accepted ethical research practices, including the use of animals and human subjects in research, scrutiny of research protocols by an institutional board of review, etc.