Fisheries research report No.161 - Distribution and abundance of juvenile pink snapper, Pagrus auratus, in the gulfs of Shark Bay, Western Australia, from trap surveys

Authors

Gary Jackson, Department of Fisheries, WAFollow
C. Burton, Department of Fisheries, Western Australia
Michael J. Moran, Department of Fisheries, WA
Ben Radford, University of Western Australia

Publication Date

4-2007

Series Number

161

Publisher

Department of Fisheries, Western Australia

City

Perth

ISBN

1 877098 99

ISSN

1035 - 4549

Abstract

Trap surveys using Antillean-Z fish traps were carried out across a range of depths and habitat types in the gulfs of Shark Bay between 1998 and 2000. Objectives of the study were (i) to evaluate the efficiency of the fish traps in catching 0+ and 1+ pink snapper (Pagrus auratus), (ii) to investigate the distribution and abundance of juvenile pink snapper in both gulfs using trap surveys, (iii) to investigate the influence of environmental factors including habitat-type on the distribution of juvenile pink snapper and, (iv) to develop trap indices of 0+ relative abundance and assess their use for monitoring of juvenile pink snapper recruitment. During the three year study, a total of 1,020 trap-sets were made and 24,248 individual fish representing more than 34 species were caught. Pink snapper were ranked 5th numerically with a total of 782 caught. Mean catch rates of 0+ and 1+ pink snapper were between 0.08-1.57 and 0.01-0.32 fish per trap hour, respectively. The distribution of 0+ pink snapper was most closely correlated with latitude and depth. Habitat-type at the majority of sites surveyed in 2000 was either seagrass meadow or sand. 0+ pink snapper were not strongly associated with any particular habitat-type based on the habitat classification system used in this study and the spatial scale at which sampling was undertaken. Although the presence/absence of 0+ pink snapper followed some predictable pattern, the variation in 0+ abundance was much less predictable. Trawl indices of 0+ relative abundance are recommended in preference to trap indices for future monitoring of juvenile pink snapper recruitment in the gulfs of Shark Bay.

Number of Pages

36

Keywords

Antillean-Z fish traps, Shark Bay, Pink snapper, Pagrus auratus, Juvenile, Recreational fishing

Disciplines

Aquaculture and Fisheries | Marine Biology | Natural Resources and Conservation | Natural Resources Management and Policy

Recommended Citation

G. Jackson, C. Burton, M. Moran, B. Radford. Distribution and abundance of juvenile pink snapper, Pagrus auratus, in the gulfs of Shark Bay, Western Australia, from trap surveys. Fisheries Research Report No. 161, Department of Fisheries, Western Australia, 36p.