Catch composition of Western Australia’s temperate demersal gillnet and demersal longline fisheries, 1994 to 1999

• Main Authors: McAuley, Rory B., Simpfendorfer, Colin A.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Department of Fisheries, Government of Western Australia 2003
• Subjects: Antarc*; antarcticus
• Online Access: https://researchonline.jcu.edu.au/8092/1/8092_Simpfendorfer_and_McAuley_2003.pdf

Catch composition data were collected from Western Australia’s temperate demersal gillnet and demersal longline fisheries, between Eucla and Geraldton, over a five-year period from July 1994 to June 1999. Results were compared to Department of Fisheries catch records compiled from fishers’ monthly catch returns. Discarded bycatch of several species was estimated by bootstrapping their observed catch rates. Dusky shark, Carcharhinus obscurus, gummy shark, Mustelus antarcticus, whiskery shark, Furgaleus macki, and Port Jackson shark, Heterodontus portusjacksoni, were identified as the main components of the fisheries’ catch, however, catches were found to vary regionally. School shark, Galeorhinus galeus, dogfish of the family Squalidae and the sandbar shark, Carcharhinus plumbeus, were regionally important in the south-east, mid-southern and west coast regions, respectively. Teleosts comprised between 5.4% and 16.6% of the total demersal gillnet and longline catch, with Buffalo bream, Kyphosus cornelii, West Australian Dhufish, Glaucosoma hebraicum and dusky morwong, Dactylophora nigricans identified as the main components of the teleost catch. Estimating catches from research catch per unit effort data indicated that catches of secondary elasmobranch species may have been underreported in commercial fishing returns. Records of non-fish bycatch were also compiled from observer data. The rates of capture of non-fish bycatch were low in all regions, with an overall occurrence of less than one capture per 1,000 kilometre gillnet hours.