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Fishery Bulletin 111(2) 
additional effects on reproductive potential of female 
Tilefish. 
Male size and age at maturity differed between years 
much more dramatically than did female size and age 
at maturity (Tables 2, 3[C and D] ). In 2008, male L 50 
was 54.1 cm FL, smaller than in 1978 (62.6 cm FL) but 
larger than in 1982 (38.6 cm FL). The same rebounding 
pattern was evident for male A 50 , but, again, the differ- 
ence in A 50 between 1978 and 1982 (2.5 years) was not 
completely regained by 2008. Grimes et al. (1988) re- 
ported the initial trend, when they concluded that high 
fishing pressure was associated with and presumably 
induced a reduced size at maturity for males between 
1978 and 1982. Our results indicate that this smaller 
size and younger age at maturity observed in 1982 did 
not become fixed. Because male fitness can be related 
strongly to size and age (Trippel, 2003), it is likely that 
male reproductive success is still hampered by reduced 
maturity parameters relative to that observed in 1978. 
The interpretation and predictability of these results, 
however, are hindered by the limited amount of data 
available to determine the stability of sex-specific ma- 
turity schedules between years. 
Early reports that maturity schedules were flexible 
and could be dynamic in response to rates of fishing 
were treated with skepticism (Beacham, 1987), but 
they are becoming increasingly common and well sup- 
ported (de Roos et ah, 2006; Conover et ah, 2009; Chu- 
wen et ah, 2011). If rates of maturation are heritable 
and survival rates of reproducing individuals are low, 
fishing will select individuals that reproduce at smaller 
sizes and younger ages (Reznick et ah, 1990; Hutchings, 
1993). If this selective pressure were to be eliminated, 
maturation rates would still likely require several gen- 
erations to rebound (Conover et ah, 2009). Tilefish have 
a minimum generation time of 5-7 years, according to 
the generation time estimated from the values of A 50 
reported here. Therefore, several generations actually 
have passed between 1982 and 2008. Also, the period 
of high exploitation (1977-87) did not extend beyond 
2-3 Tilefish generations, unlike the several decades- 
long, chronic effects of overfishing observed in some 
other fisheries (Worm et ah, 2009). Finally, Tilefish 
maturation evidently is not entirely under genetic con- 
trol because males are presumed to use proximate sex 
and size cues to determine their reproductive potential 
(Grimes et ah, 1988). In summary, we cannot rule out 
that genetic selection caused by increased fishing rates 
occurred 30 years ago for Tilefish, but we can point 
to these other factors as likely contributors to the ap- 
pearance of a rebounding maturity rate among males 
following heavy exploitation in the 1970s and 1980s. 
Conclusions 
Intersex males exist, but the northern stock of Tilefish 
is functionally gonochoristic. Current demographics in- 
dicate age truncation and the lack of any strong year 
classes in the rebuilt fishery of 2008. A macroscopic 
method for assessment of sex-specific maturity dur- 
ing the spawning season was verified as a reliable and 
cost-effective approach to monitoring trends in Tilefish 
maturation. Previously published data (Grimes et ah, 
1988) were reanalyzed, and an information-theoretic 
approach revealed differences in estimates of maturity 
ogives attributed to methods, sexes, and years. 
Once method and sex were accounted for, it was evi- 
dent that male maturation rates have rebounded from 
an earlier decline associated with a period of overex- 
ploitation. This rebound probably occurred because the 
period of overexploitation did not last long, several 
generations have passed during a period of improved 
conditions for the fishery, and male maturation is so- 
cially mediated. At present, only 3 years of age and 
maturity data exist, but these data were available for 
the 2009 Tilefish assessment, and they show the value 
of continued cooperative biological monitoring in this 
data-limited fishery. 
Acknowledgments 
The fishermen and vessel owners of the FV Sea Cap- 
ture and the FV Kimberly were cooperating partners, 
together with the assistance of the Northeast Fisher- 
ies Science Center (NEFSC) Study Fleet program: J. 
Hoey, M. Palmer, J. Moser, K. Anderson, M. Ball, and I. 
Conboy. J. Burnett, J. Brenton, S. Correia, B. Jackson, 
P. Nitschke, K. Oliveira, N. Perry, G. Shepherd, and K. 
Stokesbury also assisted materially. Funding for this 
project was provided through NOAA Fisheries Coop- 
erative Marine Education and Research program, the 
University of Massachusetts, the NEFSC Cooperative 
Research Program, and the Massachusetts Fisher- 
ies Institute. C. Grimes, R. Muller, and 3 anonymous 
reviewers provided constructive criticism on earlier 
drafts. We thank all of those involved. 
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