Trabajo presentado en el XII Conference of the Iberian Association for Comparative Endocrinology (AIEC), celebrado en Faro (Portugal), del 26 al 28 de septiembre de 2019With the use of electronic tracking technology, data on fish movements, physiology and
environmental parameters can be collected from each tagged individual. The perfect tag - small size,
lasting activity, long distance data transmission (e.g. radiotransmitters, acoustic transmitters, pop-up
satellite archival tags) - does not exist, and the choice of telemetry technology and tagging method
(external, intracelomic, intragastric) depends on fish species, life stage and research question. The
proposed solution within the AQUAEXCEL2020 EU project is a stand-alone, small and light (1 g)
device (AEFishBIT), composed of a tri-axial accelerometer, a microprocessor, a battery and an RFID
tag for quick-smart identification. The device is externally attached to the operculum to monitor
physical activity by mapping accelerations in x- and y-axes, while operculum beats (z-axis) serve as
a measurement of respiratory frequency. Initial functional validation has been made with gilthead sea
bream and European sea bass juveniles in swimming test chambers, highlighting a high correlation
of oxygen consumption and swimming activity with the calculated AEFishBIT records (MartosSitcha et al., 2019; Frontiers in Physiology 10:667). Current studies with free-swimming fish reveal
that the attachment protocol does not have a negative impact on growth performance in active feeding
fish, offering a wide range of new information based on individual behaviour: i) the switch from
nocturnal to diurnal rhythms of activity across season, ii) the different energy partitioning for growth
and maintenance, iii) the asynchrony of movements as an indirect measure of aging and adaptability
to culture environment, and iv) the different coping behaviour of fish challenged with low water
oxygen concentrations. AEFishBIT also provides reliable information of disease outcome in fish
parasitized with the intestinal myxozoan Enteromyxum leei, emerging as the ideal complement for
sensing the quality of the environment and improving selective breeding protocols.AQUAEXCEL2020 EU Project, GA 65283