**6. Acknowledgements**

Travel support provided by a bilateral Amadeus project (between Austria and France,) no. V13, made comparative studies of video footage from the Bay of Biscay UV dives possible. Special thanks to Daniel Latrouite, Pascal Lorance and Verena Trenkel, IFREMER, who provided copies of relevant video footage from OBSERVHAL and VITAL dives and assistance in behavioral data recordings. Thanks to Jan Bryn, Reidar Johannesen, and Asgeir Steinsland for assistance during MAR-ECO ROV dives. Thanks to Mirjam Bachler for valuable comments on the manuscript.
