Movements of three large coastal predatory fishes in the northeast Atlantic: a preliminary telemetry study

Juan Freire,Pablo Pita

doi:10.3989/scimar.2011.75n4759

Abstract

Labrus bergylta, Dicentrarchus labrax and Conger conger are common predators of northeast Atlantic coastal ecosystems and are studied here for the first time with ultrasonic telemetry in their natural environment. We demonstrate the viability of using this technology with these species and used movement information to obtain preliminary short-term results on site fidelity, diel activity patterns and home range sizes. Two complementary telemetry methods were used: manual and automatic tracking along a stretch of coast characterized by its high wave exposure (A Coruna, NW Spain). C. conger stayed in the area for the longest periods of time (17 days), occasionally leaving their refuges at dusk or during the night to search for food. Their home range was very small (604 m2). L. bergylta were not detected by the automatic receivers but the size of their home range (between 2874 and 5184 m2), shows that they are highly sedentary with very limited movements. D. labrax left the area for the longest periods (9 days) and were detected during both night and day. Their home range was the largest (up to 26396 m2), evidencing complex spatial behaviour on a large scale.

Highlights

It is very interesting to have accurate knowledge of the habitat use of marine predators because they are indicators of the health of the ecosystem they inhabit (Myers and Worm, 2003; Myers et al, 2007)
The recent innovations in underwater ultrasonic telemetry allow accurate information on different aspects of fish habitat use to be obtained with very high resolution (Winter, 1996, Golet et al, 2006; Jorgensen et al, 2006)
In this work we explored the potential use of telemetry techniques to investigate the movements of these species in Galician waters (NW Spain)

Summary

Introduction

It is very interesting to have accurate knowledge of the habitat use of marine predators because they are indicators of the health of the ecosystem they inhabit (Myers and Worm, 2003; Myers et al, 2007). Have been used to study movement patterns and habitat use preferences of marine animals, but these methods have limitations (Kearney, 1989, Murphy and Jenkins, 2010). The recent innovations in underwater ultrasonic telemetry allow accurate information on different aspects of fish habitat use to be obtained with very high resolution (Winter, 1996, Golet et al, 2006; Jorgensen et al, 2006). FREIRE been an increase in the number of works that use this technology to study the behaviour of different fish species (George, 2007). There is still little information about the home range size, habitat selection criteria and activity patterns of the populations of many coastal fish species (Topping et al, 2005), especially in temperate zones (Lowe et al, 2003)

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Discussion

Conclusion