1. a Department of Fisheries and Oceans, Ocean Sciences Division , Institute of Ocean Sciences , 9860 West Saanich Road, Sidney, BC, V8L 4B2
2. b P.P. Shirshov Institute of Oceanology , Russian Academy of Sciences , Moscow, Russia
3. c Department of Fisheries and Oceans , Canadian Hydrographic Service Institute of Ocean Sciences , Sidney, BC
4. d Department of Fisheries and Oceans, Ocean Sciences Division , Institute of Ocean Sciences , 9860 West Saanich Road, Sidney, BC, V8L 4B2 E-mail: