Publication Abstract

Assessment of sandeel distribution and abundance: a seabed discrimination approach

J. van der Kooij, S. Mackinson, A. Nicholls and D. Righton

The lesser sandeel (Ammodytes marinus) is an important forage and industrial fish species found in large numbers across the central and southern North Sea. Mapping their distribution and estimating abundance is difficult because they remain buried in the sediment for a large part of the year. We used the Questar Tangent Seaview (QTC) acoustic ground discrimination system to identify the acoustic characteristics of buried sandeels at fishing grounds on the Dogger Bank. This signature was subsequently used to identify the night-time distribution of sandeels within a 27 nm by 30 nm area in four successive years. The 'acoustic distributions' are compared with the distribution of different seabed types to show how the occupancy of habitat by sandeels changed over time. The results are compared to sandeel distribution data collected using standard fisheries acoustics and dredge fishing methods. We discuss how the various sources of information may lead to integrated method for the assessment of sandeel abundance.

Reference:

J. van der Kooij, S. Mackinson, A. Nicholls and D. Righton. (2004) Assessment of sandeel distribution and abundance: a seabed discrimination approach. ICES ASC Vigo, Spain, 2004