NOAA Protocols for Fisheries Acoustics Surveys and Related ...

Techniques
The primary source of these data is conductivity-temperature-depth (CTD) profiles. Also,
acoustic Doppler current profilers (ADCPs) are used to collect data on ocean currents while
underway. Expendable bathythermographs (XBTs), underway flow-through collection of
temperature and salinity near the surface, and satellite measurements of ocean properties
represent additional sources of near-surface environmental data.
The number and location of oceanographic samples should be chosen to provide assurance
that proper sound speed and absorption values have been used and to support research on the
environmental factors affecting Pacific hake distribution and abundance, taking into account
available ship time.
Sampling should follow ship-specific procedures, instrument-specific instruction from the
manufacturers of the oceanographic equipment, and protocols developed to facilitate post-cruise
processing and analysis of the data to accepted oceanographic standards (Emery and Thomson,
1997). For data management procedures for oceanographic data, see Data Management under
Protocol 2.
Error
Uncertainty, random, systematic – While useful information is immediately available from
these oceanographic instruments, post-cruise calibration QA/QC procedures by a trained analyst
(Emery and Thomson, 1997) are usually required for quantitative work.
Considerations
Remediation – Oceanographic data should be processed post-cruise by a trained analyst if they
are to be used for quantitative work.
Improvements – AUV and satellite remote sensing technologies offer major routes of future
expansion of the collection of concomitant oceanographic data.
Further details of sampling procedures are given in the technical memoranda describing the
2003 hake survey (Fleischer et al., in review) and in the FRAM Hake Acoustic Survey Manual.
References
Alverson, D.L., Larkins, H.A., 1969. Status of the knowledge of the Pacific hake resource.
California Cooperative Oceanic Fisheries Investigations Reports 13, 24-31.
Bailey, K.M., Francis, R.C., Stevens, P.R., 1982. The life history and fishery of Pacific whiting,
Merluccius productus. California Cooperative Oceanic Fisheries Investigations Reports 23, 81-98.
Campbell, R.C., 1974. Statistics for Biologists, 2nd ed. Cambridge University Press, London,
383p.
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