Figure 1.
Map of the Palm archipelago in the Great Barrier Reef Marine Park, Australia.
Table 1.
Common species of reef fishes at the Palm archipelago and their importance to spearfishers and linefishers (based on data from [4]).
Figure 2.
Maps showing the spatial arrangement of fishing zones before (A) and after (B) 1 July 2004.
Arrows show the approximate locations of survey sites within ‘no-fishing’, ‘control’ and ‘impact’ zones. The no-fishing zone (north and east Orpheus Island) has been protected from all forms of fishing since 1987. The control zone (south-west Orpheus Island) has been protected from spearfishing since 1987. The impact zone (Palm Island) was protected from spearfishing from 1987 to 1 July 2004, but spearfishing was allowed from 1 July 2004 onwards. Linefishing was allowed at control and impact zones before and after 1 July 2004. For clarity, other multi-use management zones in the Palm archipelago are not shown (see www.gbrmpa.gov.au for further information).
Figure 3.
Mean fish density (A-E), coral cover (F, G) and structural complexity (H) (±1SE) from 2004 to 2009.
Data for the no-fishing zone are shown only for the purpose of comparison. The management history of each zone is described in Figure 2. Structural complexity was defined on a scale of zero to five (see text for definitions). Means were calculated from 40 samples (underwater visual transects) per zone per year. Groups with the same letters were not significantly different.
Table 2.
Results of one-factor ANCOVA of fish density in the no-fishing zone, with habitat indices as covariatesa.
Table 3.
Results of two-factor ANCOVA comparing fish density between zones (control versus impact) and between years (2004–2009), with habitat indices as covariatesa.
Table 4.
Results of Kruskal-Wallace tests comparing the density of legal-size coral trout and stripey snapper between yearsa.
Figure 4.
Mean total length (±1SE) of coral trout (A) and stripey snapper (B) from 2004 to 2009.
Data for the no-fishing zone are shown only for the purpose of comparison. The management history of each zone is described in Figure 2. Sample sizes for control, impact and no-fishing zones were 40–62, 17–68 and 53–94 respectively. Data originate from 40 underwater visual transects per zone per year. Groups with the same letters were not significantly different.
Table 5.
Results of two-factor ANOVA comparing fish length between zones (control and impact) and between years (2004–2009)a.
Figure 5.
Length-frequency distributions of coral trout and stripey snapper.
Data originate from 40 underwater visual transects per zone per year. The management history of each zone is described in Figure 2. The x-axis labels are size-category midpoints. Minimum legal sizes of coral trout and stripey snapper are 38 and 25 cm total length respectively.
Table 6.
Results of χ2 homogeneity tests comparing size distributions of coral trout and stripey snapper in no-fishing, control and impact zones between years (2004–2009)a.