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Scalabrin, Carla; Masse, Jacques. |
Echo sounder data were used to investigate the spatio-temporal variability of shoal behaviour in the Bay of Biscay. Data collected from annual surveys were processed using MOVIES-B software in order to mcasure this variability. The software was designed to measure morphological, energetic and space-time distribution descriptors from the acoustic signal received from fish shoals. Two surveys, DAAG 90 and DAAG 91, provided the appropriate characteristics for such an analysis. The survey's objective was to obtain relative abundance indices for the anchovy (Engraulis encrasicolus) biomass in the Bay of Biscay. The surveys were carried out in the same area (southern Bay of Biscay), at the same period (April) within one year interval (1990 and 1991), using the... |
Tipo: Text |
Palavras-chave: Fish shoal; Fisheries acoustics; Bay of Biscay; Pelagic fish. |
Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00190/30111/28580.pdf |
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Mouget, Anne; Goulon, Chloé; Axenrot, Thomas; Balk, Helge; Lebourges-dhaussy, Anne; Godlewska, Malgorzata; Guillard, Jean. |
Hydroacoustics has become a requisite method to assess fish populations and allows to describe the relationships of fish with other elements of the aquatic ecosystem. This nonintrusive method is currently an integral part of the sampling procedures recommended for fish stock assessment by the Water Framework Directive and has been standardized by the European Committee for Standardization [CEN (2014) CSN EN 15910 ‐ Water quality ‐ Guidance on the estimation of fish abundance with mobile hydroacoustic methods, Category: 7577 Water quality. Biological.]. In Europe, hydroacoustic surveys are performed in freshwater using different frequencies. Consequently, there is a need to evaluate if survey results can be compared. This study aimed to carry out in situ... |
Tipo: Text |
Palavras-chave: Fisheries acoustics; Frequencies comparison; Freshwater; Hydroacoustics; Lake; Standardization. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00484/59605/62619.pdf |
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Trenkel, Verena; Berger, Laurent; Bourguignon, Sebastien; Doray, Mathieu; Fablet, Ronan; Masse, Jacques; Mazauric, Valerie; Poncelet, Cyrille; Quemener, Gael; Scalabrin, Carla; Villalobos, Hector. |
This paper provides an overview of the progress Ifremer has made recently in fisheries acoustics and the study of small pelagic fish by: i) pushing observation frontiers using a range of platforms including an autonomous underwater vehicle, AUV, ii) developing measuring instruments and methods and iii) studying fish distributions. Presently, information from several frequencies of single-beam echosounders is routinely collected together with data from the ME70 multibeam echosounder. For onboard data acquisition control the HERMES software was developed. The new MOVIES 3D software includes modules for simultaneous realistic 3D visualisation and post-processing such as bottom detection, school extraction and calculation of descriptors and integration of all... |
Tipo: Text |
Palavras-chave: Multibeam echosounder; Oceanographic AUV; Pelagic fish; Fisheries acoustics. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00000/11165/7517.pdf |
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Lefort, Riwal; Fablet, Ronan; Berger, Laurent; Boucher, Jm. |
In this letter, we address the characterization of objects in 3-D sonar images of the water column obtained by a multibeam echo sounder. Compared with classic 2-D images from a monobeam echo sounder, these 3-D images provide finer scale observation of the pelagic biomasses and new tools to characterize 3-D distributions. By viewing object patterns as realizations of spatial point processes, we investigate descriptive spatial statistics. This method is then applied to 3-D fisheries acoustics data set for characterization of the distribution of pelagic fish schools. Reported experiments illustrate the relevance of the proposed descriptors. The comparison of our method with 2-D sonar data analysis further demonstrates the information gain from using 3-D sonar... |
Tipo: Text |
Palavras-chave: Fisheries acoustics; Multibeam sensor; Object patterns in images; Point processes; Spatial statistics. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00056/16769/14270.pdf |
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