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Fishery Bulletin 119(2-3) 
T declivis—k\| 
T declivis—NSW 
E. nitidus—K| 
E. nitidus—NSW 
Year 
Figure 5 
Panels on the left show predicted temporal variation (Year) in otolith increment growth relative to the long-term mean 
(indicated by the gray dashed line at the 0 value of the y-axis in each panel) for common jack mackerel (Trachurus 
declivis) and redbait (Emmelichthys nitidus) collected off Kangaroo Island (KI; black lines) and New South Wales 
(NSW; black dashed lines) in Australia. The shaded areas above and below the lines indicate standard errors of the 
mean. Panels in the right column show predicted temporal variation in otolith increment growth for common jack 
mackerel and redbait collected off KI (circles) and NSW (triangles) based on the birth date (YearClass) of fish relative 
to the long-term mean. Predicted variation in increment growth was produced from estimates of the Year and Year- 
Class random effects (the best linear unbiased predictors). Error bars indicate standard errors of the mean. Note that 
values on the y-axis are different between species and for Year and YearClass. Common jack mackerel and redbait 
samples were collected between 2014 and 2016. 
had higher interannual variation than that of redbait from 
KI, with the observed maximum predicted growth being 
approximately 4-fold that of fish from KI (Fig. 5, C and D). 
Redbait from NSW also had a pronounced increase in 
growth from the long-term mean in 2008, but common jack 
mackerel from KI had decreased growth compared with the 
long-term mean in the same year (Fig. 5, A and D). 
YearClass variations in common jack mackerel from KI 
indicate that the 2009 cohort had greater growth than 
the long-term mean; all other cohorts had low variation 
between them (Fig. 5E). Conversely, the 2011 cohort of 
common jack mackerel from NSW had slower growth than 
the long-term mean (Fig. 5F). Three consecutive cohorts 
(2010-2012) of redbait from KI had slower growth than 
the long-term mean (Fig. 5G). Two YearClass cohorts of 
redbait from NSW had faster growth than the long-term 
mean (2005 and 2011; Fig. 5H). 
Effects of environmental conditions 
Chlorophyll-a concentrations and SSTs were both higher in 
NSW than off KI (0.56 mg/m? [SE 0.016] versus 0.22 mg/m® 
[SE 0.006] and 19.11°C [SE 0.14] versus 16.71°C [SE 0.11)). 
The top-ranked model assessing the effect of local environ- 
mental variables on growth for redbait from NSW and KI and 
for common jack mackerel from NSW was the base model, 
