456 



Fishery Bulletin 97(3), 1999 



ever, ehu have relatively large mouths, take baited 

 hooks aggressively (Ralston, 1990), and small- 

 mouthed kalekale were well-represented in our 

 catches. We therefore should have caught small, im- 

 mature ehu had they been abundant where we fished. 

 Alternatively, juvenile ehu might occupy different 

 bottom depths, as evident for several species of 

 eteline snappers elsewhere (Ralston and Williams, 

 1988; Parrish, 1989). If so, juvenile ehu inhabit con- 

 siderably different depths than do larger fish because 

 we fished at depths that were much shallower and 

 deeper than the typical ( 175-225 m ) depths at which 

 adult ehu occur in Hawaiian waters. It is more likely 

 that juvenile ehu occur in different, perhaps lower- 

 relief microhabitats at or near depths at which larger 

 conspecifics are fished in Hawaii (Clarke, 1972; 

 Struhsaker, 1973). 



Our estimate of L^q for ehu approximates the norm 

 for deepwater lutjanids: 28 cm FL is equivalent to 

 43% of its reported maximum body length in Hawai- 

 ian waters of 65 cm FL (Everson, 1984). On average, 

 deepwater insular snappers mature at about 50*^ 

 maximum body length, although values can range 

 considerably lower and higher among species 

 (Grimes, 1987). 



Researchers must not apply size-at-maturity esti- 

 mates to other populations of the same species for 

 which somatic condition (Ralston, 1988) or size-spe- 

 cific gonadal allocation might differ, because to do so 

 could result in erroneous estimates of size at matu- 

 rity. For example, body size at maturity estimated 

 for ehu in this report is applicable only to fish in the 

 Hawaiian archipelago. It is almost certain that body 

 size at sexual maturity differs among Pacific regions, 

 given the great geographic variations in average and 

 maximum body sizes and growth rates of ehu (Smith, 

 1992; Moffitt, 1993). The L^^ value for ehu in the 

 South Pacific (Vanuatu), where the species attains 

 maximum body lengths of 120 cm FL, is likely greater 

 than that for ehu in Hawaii. Conversely, our value 

 may be an overestimate in the Marianas, where ehu 

 apparently attain maximum body lengths of less than 

 half those at Vanuatu (Smith and Kostlan, 1991). 

 Improved estimates of L^q, based on more data for 

 smaller fish, are needed for ehu in Hawaii. Better 

 age and growth estimates also are needed for ehu in 

 Hawaii and elsewhere because of uncertainties in 

 present size-at-age and growth-rate estimates for the 

 species (Smith and Kostlan, 1991; Kobayashi''). 



Kalekale We provide the first direct estimates of size 

 at maturity of this species. In age and growth stud- 

 ies of kalekale from the Marianas (Ralston and Wil- 

 liams, 1988) and Hawaiian Islands (Williams and 

 Smith, 1997), deceleration in somatic growth (which 



should reflect gonadal maturation) occurred at 

 lengths of 25-30 cm FL, consistent with our esti- 

 mated size at maturity for this species. An L^q of 29 

 cm FL is about 53^^ of its estimated maximum length 

 in Hawaii (55 cm, as 105% of L^=52.5 cm FL; Fig. 4 

 in Williams and Smith, 1997), also approximating 

 the 50% norm for deepwater insular lutjanids 

 (Grimes, 1987). 



Conclusions 



We believe that gross morphometric measures, such 

 as body size, ovary weight, and egg size, can provide 

 adequate proxies for microscopic histological evidence 

 of sexual maturity in asynchronous multiple-spawn- 

 ers like eteline lutjanids in Hawaii. Applicability may 

 vary among species and may relate to the reproduc- 

 tive dynamics of females, both individually and col- 

 lectively, within spawning populations. We further 

 suggest that these types of measures can be realisti- 

 cally combined to assess sexual maturity using lo- 

 gistic regression or discriminant analysis for other 

 species of temperate and tropical marine fishes. 



Acknowledgments 



We thank all those who assisted in specimen collec- 

 tion aboard the Toivnsend Cromwell. Eric Yamanoha 

 (Pathology Department, Queen's Hospital, Honolulu) 

 diligently supervised the histological work. We also 

 thank C." Boggs, T. Clarke, D. Ellis, D. Kobayashi, J. 

 Parrish, J. Polovina, D. Somerton, and two anony- 

 mous reviewers for constructive reviews of manu- 

 script drafts, and A. Taylor for suggesting logistic 

 regression as an alternative to discriminant analy- 

 sis. BBL gratefully acknowledges the support of a 

 NOAA Junior Fellowship ( 1991-95 ) at the Honolulu 

 Laboratory of the NMFS, Southwest Fisheries Sci- 

 ence Center. 



Literature cited 



Analytical Software 



1994. STATISTDCuser'smanual, version 4.1. Analytical 

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1986. Review of the gonad index (GI) and an introduction 

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 jack tuna Kattiuwonus petamis in the Atlantic Ocean. Mar. 

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 Clarke, T. A. 



1972. Collections and submarine observations of deep 

 benthic fishes and decapod Crustacea in Hawaii. Pac. Sci. 

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