title: Abundant box jellyfish, Chironex sp. (Cnidaria: Cubozoa: Chirodropidae), discovered at depths of over 50 m on western Australian coastal reefs.
abstract: Box jellyfish cause human fatalities and have a life cycle and habit associated with shallow waters (<5 m) in mangrove creeks, coastal beaches, embayments. In north-western Australia, tow video and epibenthic sled surveys discovered large numbers (64 in a 1500 m tow or 0.05 m(-2)) of Chironex sp. very near to the benthos (<50 cm) at depths of 39-56 m. This is the first record of a population of box jellyfish closely associated with the benthos at such depths. Chironex were not widespread, occurring only in 2 of 33 tow videos and 3 of 41 epibenthic sleds spread over 2000 km(2). All Chironex filmed or captured were on low to medium relief reefs with rich filter feeder communities. None were on soft sediment habitat despite these habitats comprising 49% of all sites. The importance of the reef habitat to Chironex remains unclear. Being associated with filter feeder communities might represent a hazard, and other studies have shown C. fleckeri avoid habitats which represent a risk of entanglement of their tentacles. Most of our observations were made during the period of lowest tidal current flow in the morning. This may represent a period favourable for active hunting for prey close to the seabed.
authors.affiliation: CSIRO Oceans and Atmosphere, Private Bag 5, Wembley, 6913, Australia.|The Western Australian Marine Science Institution, Perth, Australia.
authors.forename: John K
authors.initials: JK
authors.lastname: Keesing
authors.affiliation: CSIRO Oceans and Atmosphere, Private Bag 5, Wembley, 6913, Australia.|The Western Australian Marine Science Institution, Perth, Australia.
authors.forename: Joanna
authors.initials: J
authors.lastname: Strzelecki
authors.affiliation: Australian Institute of Marine Science (AIMS), University of Western Australia Oceans Institute, (MO96), 35 Stirling Highway, Crawley, 6009, Australia.
authors.forename: Marcus
authors.initials: M
authors.lastname: Stowar
authors.affiliation: Australian Institute of Marine Science (AIMS), University of Western Australia Oceans Institute, (MO96), 35 Stirling Highway, Crawley, 6009, Australia.|The Western Australian Marine Science Institution, Perth, Australia.
authors.forename: Mary
authors.initials: M
authors.lastname: Wakeford
authors.affiliation: Australian Institute of Marine Science (AIMS), University of Western Australia Oceans Institute, (MO96), 35 Stirling Highway, Crawley, 6009, Australia.|The Western Australian Marine Science Institution, Perth, Australia.
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Miller
authors.affiliation: CSIRO Oceans and Atmosphere, GPO Box 1538, Hobart, 7001, Australia.
authors.forename: Lisa-Ann
authors.initials: LA
authors.lastname: Gershwin
authors.affiliation: Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, 264003, Yantai, Shandong, P. R. China.
authors.forename: Dongyan
authors.initials: D
authors.lastname: Liu
mesh_terms: D000818:Animals; D003063:Cnidaria; D017753:Ecosystem; D006801:Humans; D014904:Western Australia