Two acoustic surveys of pelagic fish in Hawke Bay, New Zealand, 1980
- 1 September 1985
- journal article
- research article
- Published by Taylor & Francis in New Zealand Journal of Marine and Freshwater Research
- Vol. 19 (3) , 375-389
- https://doi.org/10.1080/00288330.1985.9516102
Abstract
The design and execution of two acoustic surveys of Hawke Bay in February and September/October 1980 are described. Though the resulting acoustic data were, for technical reasons, of limited value, they illustrate the information which may be drawn from acoustic surveys. Fish distributions may be rapidly mapped, not only by area, but throughout most of the water column and over time. Qualitative observations on fish distribution may be quantified. The estimation of variance in acoustic surveys is discussed in detail with particular emphasis on the problems of systematic surveys. The role of replicate observations is stressed. Coefficients of variation for relative fish density estimates from the two surveys probably lie between 5 and 30%.Keywords
This publication has 3 references indexed in Scilit:
- Cluster Sampling Estimation of the Variance of Abundance Estimates Derived from Quantitative Echo Sounder SurveysCanadian Journal of Fisheries and Aquatic Sciences, 1982
- Variability of Line Intercept Density Estimates (A Simulation Study of the Variance of Hydroacoustic Biomass Estimates)Canadian Journal of Fisheries and Aquatic Sciences, 1981
- Digital system for recording fish echoesNew Zealand Journal of Marine and Freshwater Research, 1977