57 
Abstract — The western blue groper 
(Achoerodus gouldii) is shown to be 
a temperate protogynous hermaph- 
rodite, which spawns between early 
winter and mid-spring. Because A. 
gouldii changes body color at about 
the time of sex change, its color can be 
used as a proxy for sex for estimating 
the size and age at sex change and 
for estimating growth when it is not 
possible to use gonads for determin- 
ing the sex of this fish. The follow- 
ing characteristics make A. gouldii 
highly susceptible to overfishing: 1) 
exceptional longevity, with a maxi- 
mum age (70 years) that is by far the 
greatest yet estimated for a labrid; 
2) slow growth for the first 15 years 
and little subsequent growth by 
females; and 3) late maturation at 
a large total length (TL 50 =653 mm) 
and old age ( —17 years) and 4) late 
sex change at an even greater total 
length (TL 50 = 821 mm) and age (—35 
years). The TL 50 at maturity and 
particularly at sex change exceeded 
the minimum legal total length (500 
mm) of A. gouldii and the lengths of 
many recreationally and commercially 
caught fish. Many of these character- 
istics are found in certain deep-water 
fishes that are likewise considered 
susceptible to overfishing. Indeed, 
although fishing effort for A. goul- 
dii in Western Australia is not par- 
ticularly high, per-recruit analyses 
indicate that this species is already 
close to or fully exploited. 
Manuscript submitted 20 April 2008. 
Manuscript accepted 9 September 2008. 
Fish. Bull. 107:57-75 (2009). 
The views and opinions expressed or 
implied in this article are those of the 
author and do not necessarily reflect 
the position of the National Marine 
Fisheries Service, NOAA. 
The western blue groper ( Achoerodus gouldii), 
a protogynous hermaphroditic labrid 
with exceptional longevity, late maturity, 
slow growth, and both late maturation 
and sex change 
Peter G. Coulson 
S. Alex Hesp 
Norman G. Hall 
Ian C. Potter (contact author) 
Email address for contact author: l.Potter@murdoch.edu.au 
Centre for Fish and Fisheries Research 
School of Biological Sciences and Biotechnology 
Murdoch University 
South Street 
Murdoch, Western Australia, 6150, Australia 
Species of the family Labridae, which 
represents one of the largest and most 
speciose of all perciform families (com- 
prising 82 genera and at least 600 
species) are found in tropical and tem- 
perate coastal and continental shelf 
waters throughout the world (West- 
neat and Alfaro, 2005; Allen et al., 
2006) . On the basis of demographic 
analyses of large labrid species, Choat 
et al. (2006) concluded that they are 
characterised by relatively short life 
spans and indeterminate growth 
rates, namely, growth does not tend 
to an asymptote. However, a few spe- 
cies have substantial life spans; the 
oldest ages yet recorded for a labrid 
are 30-35 years (Gillanders, 1995a; 
Choat and Robertson, 2002; Choat et 
al., 2006). 
Most of the biological studies on 
labrids have been undertaken on sub- 
tropical and tropical species (Denny 
and Schiel, 2002). These studies have 
shown that many members of this 
family are protogynous hermaphro- 
dites, namely they change from female 
to male (e.g., Reinboth, 1970; Candi 
et al., 2004; McBride and Johnson, 
2007) . Sex change in these labrids 
is often accompanied by a change in 
body color and they are thus sexu- 
ally dichromatic (Warner and Robert- 
son, 1978; Shapiro, 1981; Gillanders, 
1995a). Among labrids, a few species 
change from one sex to another and 
then back again, and thus undergo 
what is termed reversed sex change 
(Ohta et al., 2003; Kuwamura et al., 
2007), and a number are gonochoris- 
tic, i.e., do not undergo sex change 
(Dipper and Pullin, 1979; Bentiveg- 
na and Benedetto, 1989; Sadovy de 
Mitcheson and Liu, 2008). However, 
a recent study of the green humphead 
parrotfish (Bolbometopon muricatum) 
has emphasised that a definitive con- 
clusion as to whether certain species 
in this family are protogynous her- 
maphrodites or gonochorists can be 
difficult to ascertain, even when there 
is detailed information on such fea- 
tures as the size compositions of the 
two sexes and the histological char- 
acteristics of their gonads (Hamilton 
et al., 2008). 
The western blue groper (Acho- 
erodus gouldii) is found throughout 
southern Australia, southwards from 
the Houtman Abrolhos Islands at 
28°30'S, 113°40'E on the west coast 
and eastwards along the south coast 
to Portland in Victoria at 38°21'S; 
141°36'E (Hutchins and Swainston, 
1986; Gommon et al., 1994) but is 
most abundant on the south coasts 
of Western Australia and South Aus- 
tralia. This species is reported to 
attain a maximum length of 175 cm 
(Gommon et al., 1994), which, among 
labrids, is apparently exceeded only 
by the humphead wrasse (Cheilinus 
undulates) (Sadovy et al., 2003). Al- 
though A. gouldii is the second most 
