Preliminary observations on the effects of artificial light on the marine environment, with special reference to three fish species of commercial value protected by Miramare Marine Reserve

Aims of this study are to give a contribution to the knowledge on the widespread use of light fishing in the Gulf of Trieste, and to obtain a preliminary evaluation of the effects of light fishing on a marine protected area, to improve the quality of marine resource management. The work consists of two main sections: the first one consists of several measurements of underwater light attenuation data collected in the marine environment, characterising the attenuation spectral distribution of different fishing lamps and plotting their vertical profiles of light attenuation in seawater; the second one regards the effects of artificial light on fish behaviour were investigated in laboratory conditions, evaluating levels of aggregation, phototaxis and photokinesis in three species of commercial interest: the sea bass (Dicentrarchus labrax), the common grey mullet (Mugil cephalus), and the sea bream (Sparus aurata). All species responded actively to variations in light intensity, and to some extent to lights of different colours. In continuation to this study, we are currently attempting to transfer the approach used in the aquarium to open sea conditions, utilizing echosounder and fixed recording systems to collect the data.