Acoustic Telemetry: A Tool to Monitor Fish Swimming Behavior in Sea-Cage Aquaculture

Lidia Muñoz,Pablo Arechavala-Lopez,João L Saraiva,Miquel Palmer,Eneko Aspillaga

doi:10.3389/fmars.2020.00645

Abstract

Acoustic telemetry techniques are very useful tools to monitor in detail the swimming behaviour and spatial use of fish in artificial rearing environments at individual and group levels. We evaluated the feasibility of using passive acoustic telemetry to monitor fish welfare in sea-cage aquaculture at an industrial scale, characterizing for the first time the diel swimming and distribution patterns of gilthead seabream (Sparus aurata) at fine-scale. Ten fish were implanted with acoustic tags equipped with pressure and acceleration sensors, and monitored in a commercial-size sea-cage for a period of one month. Overall, fish exhibited clear differences in day vs night patterns both on swimming activity and vertical distribution throughout the experiment. Space use increased at night after the implementation of structural environmental enrichment in the sea-cage. Acoustic telemetry may represent an advancement to monitor fish farming procedures and conditions, helping to promote fish welfare and product quality.

Highlights

Production systems in fin-fish aquaculture, in particular intensive farming, can cause stress, pain, health problems, and even mortality at any stage of the production process (Broom, 2007)
Swimming behavior is a common additional indicator that can be affected by water quality, population densities, feeding regimes, and Tracking Seabream Behavior in Sea-Cages diseases; group swimming behavior and spatial distribution may be used as operational on-farm welfare indicators to evaluate hunger, stress level and general health status of fish (Martins et al, 2012; Sneddon et al, 2016; Alfonso et al, 2020a)
Acoustic telemetry techniques are very useful tools to monitor in detail the swimming behavior and spatial use of the fish in the rearing environment at both individual and group levels (Baras and Lagardère, 1995)

Summary

Introduction

Production systems in fin-fish aquaculture, in particular intensive farming, can cause stress, pain, health problems, and even mortality at any stage of the production process (Broom, 2007). Behavioral studies are increasingly occupying an important place in welfare research, since behavioral responses are an early and observable response to adverse conditions or stressful stimulus, often specific for each stressor. They can be used as non-invasive indicators of stress or changes in welfare (Martins et al, 2012). Common indicators of poor welfare include, for example, changes in foraging behavior, ventilatory activity, aggression, and stereotypic or abnormal behaviors Such responses are fast and easy to observe, but they can be variable over time and difficult to quantify (Martins et al, 2012; Noble et al, 2018). Swimming behavior is a common additional indicator that can be affected by water quality, population densities, feeding regimes, and Tracking Seabream Behavior in Sea-Cages diseases; group swimming behavior and spatial distribution may be used as operational on-farm welfare indicators to evaluate hunger, stress level and general health status of fish (Martins et al, 2012; Sneddon et al, 2016; Alfonso et al, 2020a)

Objectives

Methods

Results

Conclusion