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Symposium theme: Current status of mobile and static sampling gears used
in resource surveys - studies on survey gear design and use, including new
innovations to meeting ecosystem survey requirements.
The Development of Sand Lance Survey Gear and Techniques
Participants:
- Dr. Les Kaufman, Boston University
- Clifford Goudey, Massachusetts Institute of Technology
- Olivia Free, Massachusetts Fishermen's Partnership
- Captain Bill Lee , F/V Ocean Reporter, Rockport, Massachusetts
- Captain Phil Michaud F/V Susan C III, Provincetown, Massachusetts
Sand lance are primary forage species for many commercially important stocks
for which the Western Gulf of Maine is famous. The two local species of sand
lance shelter by burying in the sand at night but feed in the water column by
day in immense schools. Thus, sand lance are likely a significant link
between the benthic and pelagic compartments of the Gulf of Maine ecosystem
and offer a key to understanding large-scale biomass movements. The cyclical
abundance of sand lance profoundly impacts commercial and recreational
fishermen, the whale watch industry, endangered and protected species, and
the biological dynamics of the ecosystem that supports these and other marine
resources in the New England region. However, currently used survey methods
are unable to adequately assess the spatial and temporal abundance of these
two elusive species.
Two sand lance survey methods have been developed as part of a project titled
“A Biological Study of Sand Lance in the Southern Gulf of Maine” being
supported by the Northeast Consortium. The first is an adaptation of a small
beam trawl that can capture sand lance when they are near the seabed. A
second is a water column corer that is being used to measure the abundance of
sand lance in pelagic schools. This gear is a 6 sq. m. drop net with a
closure mechanism that prevents escapement once the net reaches bottom. The
performance and operation of both gears were optimized using video
observation techniques.
Accompanying this gear development work has been laboratory work to identify
new characters for separating the inshore (Ammodytes americanus) and
the offshore species (Ammodytes dubius). Progress has also been made
in understanding the functional morphology of the sand lance jaw and
behaviors related to feeding and swimming. Preliminary survey results and
in-situ observations will be presented.
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