Cooperative Research Paired Trawl Sweep Comparison Study

In the spring of 2009, Northeast Fisheries Science Center (NEFSC) replaced the previous standard bottom trawl gear (Yankee 36) with a new standard survey trawl designed in close collaboration with the fishing industry and local net manufacturers. Some stakeholders expressed concern that the rockhopper sweep introduced with this gear was not suitable for the efficient capture of flatfish and could therefore bias survey estimates. To address this question, a paired trawl experiment was conducted during the fall of 2009 and the spring and fall of 2010 aboard three chartered fishing vessels, the Mary K, the Moragh K, and the Endurance. The new standard survey trawl with rockhopper sweep was compared with an identical net with a 3” cookie sweep using paired tows between 2 vessels. Results in general showed significantly more flatfish caught with the cookie sweep, although differences in size distributions between the two sweeps were negligible in most cases.

To compare catchability of rockhopper and cookie sweeps on the NEFSC standard bottom trawl survey net and allow more direct comparability between NEFSC bottom trawl survey and NEAMAP bottom trawl survey.

Available to qualified researchers.

Please contact Point of Contact via email.

NEFSC Data Access Procedure:

1. Formal request in writing usually to the data owner/contact or Center Director;

2. Requester is contacted by data owner to review and verify the request content and details for data delivery options.

3. If data is confidential then owner will determine if the data may be released to the requester;

4. If data can be released, the data is downloaded and packaged for delivery electronically; or the requester may be directed to where the data is available online.

User must read and fully comprehend the metadata prior to use. Applications or inferences derived from the data should be carefully considered for accuracy.

NEFSC Data Access Constraint:

If data is stored on an internal NEFSC network, the requester may not have direct access to query the data unless they are also authorized for network access.

Acknowledgement of NOAA/NMFS/NEFSC, as the source from which these data were obtained in any publications and/or other representations of these, data is suggested.

Oracle database on Centralized Database Management System

Data validation during data collection using FSCS 1.6, Data auditing post-survey by established auditing routines, Data validation during database load

Archiving solution for Oracle Data Sets is yet to be determined

Archival of source data preserving unaltered collected data, Scheduled backups, Remote storage backups, Password protection.

Vessel sensor data were collected electronically using SCS. Catch and biological data were collected electronically using FSCS 1.6. At the completion of the cruise, a database copy was inserted into the shoreside database.