Hostetter and Munroe: Age, growth, and reproduction of Tautoga onitis 



59 



terference spawning during activities of territorial 

 males. Reproductive behavior of individual male tau- 

 tog is flexible and influenced by both size and sexual 

 composition of the population. For example, in some 

 situations with co-dominant males, or when males 

 greatly outnumbered females, group spawning occurred 

 even among dimorphic males that in previous experi- 

 ments exhibited strong territoriality and more typi- 

 cally attempted only exclusive pair-spawning with fe- 

 males (Olla et al. 1981). Diandric males, each with 

 different reproductive behaviors, have been reported 

 for hermaphroditic labrids (Robertson & Choat 1974, 

 Warner 1975, Warner & Robertson 1978, Dipper & 

 Pullin 1979, Pottle & Green 1979a) and scarids (Warner 

 & Downs 1977, Robertson & Warner 1978). However, 

 diandric males not resulting from sexual inversions, 

 but with different reproductive strategies, have also 

 been reported (Pottle & Green 1979a,b) in cunner 

 Tautogolcibrus adspersus, another temperate species 

 of wrasse co-occurring throughout most of the geo- 

 graphic range of the tautog. 



Plasticity of male reproductive behavior, presence of 

 diandric males in the population, and skewed size and 

 sex-ratios indicate that reproduction in tautog is more 

 complex than recognized previously. Many of these 

 same characteristics are paralleled in protogynous her- 

 maphroditic labrids. In fact, protogynous hermaphro- 

 ditism is one of the more common reproductive strate- 

 gies utilized by labrids (Roede 1972, Warner & 

 Robertson 1978). Earlier researchers (Chenoweth 1963, 

 Cooper 1967) did not consider that tautog might be 

 hermaphroditic; others (Olla & Samet 1977) recog- 

 nized such possibilities, but, as yet, no evidence based 

 on histological examination of gonads exists to prove 

 or disprove the occurrence of hermaphroditism in this 

 species. In view of the complex reproductive biologies 

 of other labrids, further study on reproductive biol- 

 ogy of tautog is warranted and is currently under 

 investigation. 



Growth rates of tautog, other labrids, 

 and reef fishes 



Few published age-growth studies on labrids exist, un- 

 doubtedly because most are tropical species that have 

 proven difficult to age reliably and few have commer- 

 cial or recreational value. However, growth rates avail- 

 able for temperate labrids from the eastern and west- 

 ern Atlantic and eastern Pacific indicate slow growth 

 rates and generally extended longevities in these spe- 

 cies (Fig. 12), similar to those reported for tautog. It is 

 possible that slow growth and extended longevities are 

 characteristic not only of relatively large-sized tem- 

 perate labrids, but also may be an inherent feature of 

 growth patterns in large-sized labrids in general. 



E 



E 600- 



•i 500- 

 J 400- 



o 



S 300- 

 < 



u 200 



L bergylta 



T. adspers 



10 15 20 



AGE (yrs) 



Figure 1 2 



von Bertalanffy growth curves for selected species of temper- 

 ate and subtropical species of wrasses (Family Labridae). Spe- 

 cies represented and information sources for data presented 

 in figure are: TX=Tautoga) onitis , Rhode Island (Cooper 1965), 

 Virgina, this study; SX=Semicossyphus) pulcher, Warner 1975; 

 LX=Labrus) bergylta. Dipper et al. 1977; TX=Tautogolabrus) 

 adspersus, Serchuk & Cole 1974. 



Coefficients derived from the von Bertalanffy growth 

 equation provide insights into ecological strategies, es- 

 pecially in direct comparisons among diverse taxa 

 (Table 10). Manooch (1979) considered fishes such as 

 the bluefish Pomatornus saltatrix, Atlantic menhaden 

 Brevoortia tyrannus, and king mackerel Scomber- 

 omorus cavalla, which have relatively high /C-values 

 (0.23-0.39) indicative of fast growth rates, as the 

 coastal pelagic guild. Species with slower growth rates 

 (K usually <0.22) and generally longer lived, on the 

 other hand, were grouped together as the snapper- 

 grouper guild. These fishes represent a wide spectrum 

 of distantly related taxa including temperate labrids, 

 reef-dwelling snappers and groupers, and other dem- 

 ersal fishes such as tilefish Lopholatilus 

 chamaelonticeps which inhabits burrows on the conti- 

 nental shelf. Based on categories of growth coefficients 

 adopted by Manooch (1979), we include the tautog in 

 the snapper-grouper guild. This type of comparison, 

 which crosses phylogenetic and demographic lines, sug- 

 gests similarities in selection patterns for growth rates 

 among species inhabiting areas where spatial resources 

 may be limited. 



Conclusions and management 

 considerations 



Growing recreational and commercial fisheries for tau- 

 tog, limited amounts of natural habitat available in 



