Smooth Bottom Net Trawl Fishing Gear Effect on - New England ...

effort, the critical pulse disturbance would be identified for the two fishing sites. This would
include estimating the theoretical upper limit of trawling frequency that would compromise
secondary productivity and the optimal trawling frequency for maintaining the bottom in a state
of exponential recruitment.
A Phase II study would include a field verification program to test the validity of the model
predictions. This approach could provide important management insight into optimizing
demersal fishing frequency in the New England coastal zone at two end-member sites and
provide a protocol for extending the approach to other areas of EFH management interests. It is
likely that the theoretical model outputs proposed here would be directly useful for
Massachusetts Bay but that alternative simulation runs using different input variables would be
required to extend the predictions to other zoogeographic provinces and marine climates (e.g.
south of Cape Cod).
The Phase II work could also include a special effort to locate REMOTS® images within trawl
door furrows in order to fill in data gaps identified in the 2002 trawling study. This can be done
by mounting a downward-looking video camera on the REMOTS® frame. A shipboard video
monitor can be used to guide the operator to deploy the camera when the vessel has drifted over
a trawl door mark. In addition, by using digital cameras with high memory capacity, the SPI
systems are now capable of taking hundreds of high resolution images, further ensuring that
images would be collected within the door furrows. Because the trawl door furrows represent
the most intense disturbance of the bottom, one may expect the greatest impact of smooth bottom
otter trawl gear to be focused in these features. These same features are known to attract
demersal fish and macrocrustaceans in their foraging activities (Burrows, et al., 2003).
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