REPRODUCTION, GROWTH, AND OTHER ASPECTS OF 



THE BIOLOGY OF THE GOLD SPOT HERRING, 



HERKLOTSICHTHYS QUADRIMACULATUS (CLUPEIDAE), 



A RECENT INTRODUCTION TO HAWAII 1 



Vern R. Williams and Thomas A. Clarke 2 



ABSTRACT 



The gold spot herring, Herklotsichthys quadrimaculatus, was introduced to Hawaii by unknown means prob- 

 ably in the early 1970s and apparently spread and increased in abundance very rapidly. On the island of 

 Oahu, it has been regularly present in inshore areas since 1976 and has been most abundant during late spring to 

 early fall. Among adult fishes sampled, females slightly outnumbered males in seine collections by day in 

 shallow water, but males predominated in nighttime collections from deeper water. Both sexes began to ma- 

 ture at 75-80 mm SL and females carried distinct size groups of nearly mature ova by 90 mm SL. Gonad to 

 somatic weight ratios from both sexes indicated a spring-to-fall spawning season with a midsummer peak. 

 Batch fecundity of females was 1,100-6,300. There was no direct evidence of multiple spawning, but secondary 

 size groups of small ova were observed in some females which also carried a distinct batch of larger ova. Hold- 

 ing experiments showed that juveniles deposit daily growth increments on sagittae. Age estimates from in- 

 crement counts offish 17-121 mm long indicated that herring metamorphose at about 1 month, mature at 5-6 

 months, and probably live no more than 1 year. The reproductive life span of females appears long enough to 

 ripen more than one batch of ova. 



Only three species of marine clupeid fishes are known 

 to occur in Hawaii. The round herring, Etrumeus 

 micropus, and the sprat, Spratelloid.es delicatulus, are 

 both native to the islands, while the Marquesan sar- 

 dine, Sardinella marquesensis, was introduced in the 

 late 1950s in hopes of increasing the supply of bait- 

 fish for the local skipjack tuna fishery. The intro- 

 duction was successful in that S. marquesen- 

 sis reproduced and spread throughout the islands 

 soon afterwards, but the species never became abun- 

 dant nor contributed significantly to local baitfish 

 catches (Murphy 1960; Hida and Morris 1963). 



In 1975, small clupeids began to appear regularly in 

 Kaneohe Bay on the island of Oahu and by 1976 had 

 become very abundant both in the bay and apparent- 

 ly at other areas of Oahu. Because these fishes closely 

 resembled Marquesan sardines and no other similar 

 species was expected to occur in Hawaii, we blithely 

 assumed them to be S. marquesensis. Their sudden 

 obvious presence and consistent occurrence in 

 various collections for other purposes prompted us 

 to undertake further sampling in order to investigate 

 their biology in Hawaii. 



After the study had been largely completed, careful 



'Contribution No. 670, Hawaii Institute of Marine Biology. 



'Department of Oceanography and Hawaii Institute of Marine 

 Biology, University of Hawaii, P.O. Box 1346, Kaneohe, HI 96744- 

 1346. Address all correspondence to Clarke. 



examination of a few specimens by W. J. Baldwin of 

 the Hawaii Institute of Marine Biology and subse- 

 quent rechecking of our material plus more recent 

 collections showed that we were not dealing with the 

 Marquesan sardine, but rather with the gold spot her- 

 ring, Herklotsichthys quadrimaculatus. No attempts 

 to introduce H. quadrimaculatus to Hawaii have been 

 reported and, although its range is uncertain due to 

 probable misidentification in many reports, there is 

 no evidence that it occurs naturally anywhere within 

 ca. 3,500 km of Hawaii. Thus our study became one of 

 an apparently inadvertently introduced species, 

 whose introduction was considerably more success- 

 ful than the more carefully planned introduction of 

 the Marquesan sardine. 



This paper summarizes available data on the in- 

 troduction and spread of//, quadrimaculatus, briefly 

 considers several aspects of its general biology in 

 Hawaii, and presents results of investigations of its 

 reproduction and growth. In the course of the latter 

 we demonstrate that growth increments on otoliths 

 are valid estimates of age in days as has already been 

 shown for several temperate and tropical species in- 

 cluding the Hawaiian anchovy or nehu, Stolephorus 

 purpureus (Struhsaker and Uchiyama 1976). Al- 

 though there are few comparable data on other tropi- 

 cal clupeids, some comparisons and contrasts of H. 

 quadrimaculatus' life history pattern with those of 



Manuscript accepted December 1982. 

 FISHERY BULLETIN: VOL. 81, NO. 3, 1983. 



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