Hyndes et a I.: Age composition, growth, reproductive biology, and recruitment of Sillaginodes punctata 
267 
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650 
600 
550 
500 
450 
400 
350 
300 - 
250 - 
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Figure 8 
(A) Total lengths and (B) ages at capture, of female and male 
Sillaginodes punctata with immature (stages II— IV ) and mature 
or recovering or spent (or both) (stages V-VIII) gonads collected at 
different depths by recreational fishers in the inner-shelf waters 
of the lower west coast of Australia. 
Aldrichetta forsteri, which also both spawn in 
winter in southwestern Australia and whose 
juveniles soon after enter estuaries in large 
numbers (Thomson, 1957b; Chubb et al., 
1981). 
Sillaginodes punctata typically remains in 
sheltered nearshore marine and estuarine 
waters until it reaches ca. 250 mm in length 
and ca. 1.5 years of age (Robertson, 1977; Pot- 
ter et al., 1983; Loneragan et al., 1989; Potter 
et al., 1993; Potter and Hyndes, 1994; Hyndes 
et al., 1996a). Thus, unlike smaller species of 
whiting, such as Sillago burrus and Sillago 
vittata, which typically move offshore at 
lengths of ca. 100 mm and at ages of three to 
nine months (Hyndes et al., 1996a, 1996b), S. 
punctata remains in its nursery habitats for a 
far longer period. Because S. burrus and S. 
vittata reach maturity at the end of their first 
year of life, whereas most S. punctata first at- 
tain maturity at the end of their fourth year of 
life, this last species takes advantage of the pro- 
ductive waters of marine embayments or estu- 
aries for a longer period before migrating out 
into spawning grounds in deeper marine waters. 
Because the nursery areas of S. punctata 
are located initially in nearshore waters and 
subsequently in the deeper waters of marine 
embayments and estuaries, whereas adults 
occupy areas in and around reefs where wa- 
ter depths are generally greater, this species 
migrates offshore from shallow nursery 
grounds as it approaches the size and age at 
which it will become mature. A movement off- 
shore as body size increases parallels that re- 
corded for populations of S. punctata in south- 
eastern Australia and for other whiting spe- 
cies (Scott, 1954; Gilmour, 1969; Robertson, 
1977; Weng, 1986; Burchmore et al., 1988; 
Hyndes et al., 1996a; Caton 1 ). Although an- 
glers often caught S. punctata in deeper wa- 
ters near reefs or at the edges of adjacent 
seagrass beds, they rarely caught them during ex- 
tensive trawling over the expansive open, sandy ar- 
eas of the same region where large numbers of other 
whiting species were caught (Hyndes et al., 1996a). 
The presence of mature and recovering or spent go- 
nads in the larger members of S. punctata caught in 
areas around reefs also suggests that, unlike the 
three whiting species Sillago burrus, S. vittata, and 
S. bassensis, which migrate out into the more open 
and sandy areas of the inner shelf to spawn (Table 2; 
Hyndes et al., 1996b; Hyndes and Potter, 1996), S. 
punctata spawns in areas in and around reefs or at 
the edges of adjacent seagrass beds. Furthermore, 
whereas S. burrus and S. vittata move into spawn- 
ing grounds ranging from 5-15 m in depth, and S. 
bassensis migrates into more offshore waters where 
the depth is 20-35 m deep (Hyndes et al., 1996a, 
1996b; Hyndes and Potter, 1996), S. punctata spawns 
at depths that range from six to at least 50 m. 
Implications for management 
Because S. punctata exhibits size-related offshore 
movements, that involve firstly a movement from 
nearshore nursery areas to deeper waters in marine 
embayments and estuaries and subsequently a move- 
