Comparisons of echo-integration performance from two multiplexed echosounders

Gavin J. Macaulay*, Ben Scoulding, Egil Ona, Sascha M.M. Fässler

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

5 Citations (Scopus)

Abstract

A time-series of acoustically derived aquatic biomass estimates relies on the acoustic equipment maintaining the same performance throughout the time-series. This is normally achieved through a regular calibration process. When the acoustic equipment changes it is necessary to verify that the new equipment produces a similar result to the old equipment, otherwise an unknown bias can be introduced into the time-series. The commonly used Simrad EK60 echosounder has been superseded by the Simrad EK80 echosounder and the performance of these two scientific echosounder systems was compared using interleaved pinging through the same transducer. This was repeated for multiple transducer frequencies (18, 38, 70, 120, and 200 kHz) and from two vessels (Norway’s G.O. Sars in the North Sea and The Netherlands’ Tridens in the Northeast Atlantic Ocean). The broadband facility of the EK80 was not used. Regressions of the grid-integrated backscatter from the two systems were
highly linear. The difference in area backscattering coefficients in typical survey conditions was less than 0.6 dB (12%) at the main survey frequency of 38 kHz. In most conventional fish acoustic surveys, the observed differences are less than other sources of survey bias and uncertainty.
Original languageEnglish
Pages (from-to)2276–2285
JournalICES Journal of Marine Science
Volume75
Issue number6
Early online date7 Sep 2018
DOIs
Publication statusPublished - 1 Nov 2018

Keywords

  • Acoustic survey
  • echo-integration
  • echosounder
  • EK60
  • EK80
  • intercomparison

Fingerprint

Dive into the research topics of 'Comparisons of echo-integration performance from two multiplexed echosounders'. Together they form a unique fingerprint.

Cite this