Journal Article

Simultaneous Sv and TS measurements on Young-of-the-Year (YOY) freshwater fish using three frequencies

J Guillard, A Lebourges-Dhaussy and P Brehmer

in ICES Journal of Marine Science

Published on behalf of ICES/CIEM

Volume 61, issue 2, pages 267-273
Published in print January 2004 | ISSN: 1054-3139
Published online January 2004 | e-ISSN: 1095-9289 | DOI: http://dx.doi.org/10.1016/j.icesjms.2003.11.007
Simultaneous Sv and TS measurements on Young-of-the-Year (YOY) freshwater fish using three frequencies

More Like This

Show all results sharing these subjects:

  • Environmental Science
  • Marine and Estuarine Biology

GO

Show Summary Details

Preview

In autumn, the fish population above the thermocline in Lake Annecy mainly comprises young perch (Perca fluviatilis) of the year. The fish are distributed in schools during the day and as scattered individual fish targets at night. Measurements of volume-backscattering strength and target strengths (TS) were carried out in a synchronous way using three echosounders operating at three frequencies (70, 120, and 129 kHz), with different characteristics (split beam, dual beam, beam shape, pulse length, etc.). Target-strength values show variability from one elementary sampling unit to another and from one device to another, but the mean global TS values are similar, independently of the frequency. The volume-backscattering strengths measured on precise schools by the three acoustic devices give significantly similar results. Acoustic measurements on YOY perch are completely independent of the frequency and the characteristics of the echosounders.

Keywords: dual beam; freshwater; lake; multi-frequency; Perca fluviatilis; split beam; target strength

Journal Article.  2702 words.  Illustrated.

Subjects: Environmental Science ; Marine and Estuarine Biology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.