Adaptive behaviours of the jellyfish Aurelia labiata in Roscoe Bay on the west coast of Canada

Four behaviours of mature Aurelia labiata medusae (Scyphozoa) were observed. Touching the manubrium with a soft, hollow, silicone rubber ball or a foam rubber ball caused medusae at a depth of 1 m to swim to the surface. Dense aggregations of medusae did not form within 5 m of rock walls. Medusae did not swim into water with salinity <20 parts per thousand. Sunlight-stimulated directional swimming was to the west. These behaviours add to a growing list of adaptive behaviours of Aurelia labiata medusae. (C) 2007 Elsevier B.V. All rights reserved.