出版社：Government of Western Australia / Department of Fisheries
摘要：Trap surveys using Antillean-Z fish traps were carried out across a range of depths and habitattypes
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.
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