Status of Stocks & Multispecies Assessment Program
Through-Ice Sampling Workshop
Libby Logerwell and Kim Rand from the Status of Stocks & Multispecies Assessment (SSMA) Program's Fishery Interaction Team (FIT) organized a workshop on methods for sampling the marine environment under the ice. The workshop was held at the University of Alaska Fairbanks on 7-8 November 2007. Participants included fishery biologists; fisheries acousticians; physical and biological oceanographers; and researchers with expertise in the operation of underwater vehicles, scientific diving, and the logistics of establishing ice camps. The purpose of the workshop was to gather information on state-of-the-art methods for fish and oceanographic surveys of the Beaufort Sea shelf during ice-covered periods.
The workshop was funded by the Interior Department's Minerals Management Service (MMS). The MMS has also provided funding to the AFSC for a pilot survey and test of hypotheses in the Beaufort Sea during an ice-free period. Scientists from the AFSC and their collaborators at the University of Washington and University of Alaska Fairbanks will conduct this survey during August-September 2008 (http://www.afsc.noaa.gov/hepr/losi.php).
The distribution and abundance of fish will be assessed with bottom trawls and fisheries hydroacoustics. The distribution of zooplankton will be sampled with bongo nets and oceanographic properties will be measured with conductivity-temperature-depth probes. Although the survey will take place in ice-free waters, one of the project goals is to provide MMS with recommendations for how to optimally conduct an analogous survey during ice-covered periods. This was the motivation for the Through-Ice Sampling Workshop.
The following techniques for fish sampling were addressed: net sampling, fisheries acoustics (including DIDSON), and video cameras. Oceanographic sampling was also included in the agenda. Methods for deploying nets and instruments were discussed, specifically: remotely and autonomously operated vehicles and scientific diving. Finally, the logistics of establishing and maintaining ice camps were addressed.
The primary outcome of the workshop will be a review of methods and recommendations for a full winter survey that would accomplish the goals of the MMS. In other words, methods suitable for a survey of ice-covered waters over the Beaufort Sea shelf that would replicate, to the extent feasible, the summer survey in ice-free waters described above. The workshop also provided the opportunity for potential collaborations between institutions and individuals to be identified.
