Skip Navigation


ICES Journal of Marine Science: Journal du Conseil Advance Access originally published online on May 9, 2009
ICES Journal of Marine Science: Journal du Conseil 2009 66(6):1238-1244; doi:10.1093/icesjms/fsp122
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
66/6/1238    most recent
fsp122v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Ryan, T. E.
Right arrow Articles by Macaulay, G. J.
PubMed
Right arrow Articles by Ryan, T. E.
Right arrow Articles by Macaulay, G. J.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2009 International Council for the Exploration of the Sea. Published by Oxford Journals. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

This article appears in the following ICES Journal of Marine Science issue: The Ecosystem Approach with Fisheries Acoustics and Complementary Technologies [View the issue table of contents]

Measurement and visual verification of fish target strength using an acoustic-optical system attached to a trawlnet

Tim E. Ryan1, Rudy J. Kloser1 and Gavin J. Macaulay2

1 CSIRO Marine and Atmospheric Research, PO Box 1538, Hobart 7001, Australia
2 National Institute of Water and Atmospheric Research Ltd, PO Box 14-901, Kilbirnie, Wellington, New Zealand

Correspondence to T. E. Ryan: tel: +61 3 62325291; fax: +61 3 62325000; e-mail: tim.ryan{at}csiro.au.

Ryan, T. E., Kloser, R. J., and Macaulay, G. J. 2009. Measurement and visual verification of fish target strength using an acoustic-optical system attached to a trawlnet. – ICES Journal of Marine Science, 66: 1238–1244.

It is difficult to make acoustic target-strength (TS) measurements of fish behaving naturally in deep-water habitats. The fish may avoid the acoustic instrumentation, and, if measured, there is uncertainty about their species and their orientation relative to the incident sound. To address these issues, a novel acoustic-optical system (AOS) has been developed, which combines a battery-powered, dual-frequency, split-beam acoustic system with a low-light video camera. The AOS attaches to the headline of a commercial deep-water demersal trawlnet that herds fish past the AOS and to the codend. This paper describes initial trials of the AOS to measure calibrated TS of New Zealand orange roughy, validated with video images. The fish species were visually identified, and their behaviour and orientation were approximated. The trawl catch provided associated samples for species identification and measurements of their length and other biological metrics. The combination of acoustics and optics in a net-mountable system constitutes a powerful sampling tool with broader applications in fishery research and ecosystem investigations.

Keywords: acoustic-optical system, acoustics, deep-water ecosystem, optics, orange roughy, target strength

Received 7 August 2008; accepted 14 December 2008; advance access publication 9 May 2009.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 ICES J. Mar. Sci.Home page
R. J. Kloser, T. E. Ryan, J. W. Young, and M. E. Lewis
Acoustic observations of micronekton fish on the scale of an ocean basin: potential and challenges
ICES J. Mar. Sci., July 1, 2009; 66(6): 998 - 1006.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.