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Fishery Bulletin 92(4). 1994 



descriptive early life history information for two ad- 

 ditional geographic regions: the Mediterranean Sea 

 (Aboussouan, 1989) and the west central Atlantic 

 (Richards, 1990). Publications summarizing devel- 

 opment of fishes in other major geographic regions 

 (e.g. Southeast Pacific) are not available. We com- 

 piled data from the published guides as well as from 

 the more recent, but restricted, publications on the 

 basis of the illustrations of eggs and larvae they con- 

 tained and then compared our results with those of 

 Richards (1985) who summarized early life history 

 information available at that time based on the work 

 of Moser et al. ( 1984). We employed six early life his- 

 tory stages (egg, yolk sac, preflexion, flexion, post- 

 flexion, and transforming) and considered a particu- 

 lar stage of a species as known if an illustration of 

 that stage had been published. The quality of egg 

 and larval illustrations varies, and we subjectively 

 excluded those that we thought would be inadequate 

 for identifying plankton-collected specimens. Since 

 accurate species lists were not always available in 

 the guides, some subjectivity was involved in deter- 

 mining the number of species present in a region. In 

 cases where the geographic regions covered by early 

 life history guides were more restricted than those con- 

 sidered in regional species lists we used the lists found 

 in the guides. Paxton et al. (1989) was also consulted 

 for the number of species in several regions. Although 

 information was available for eggs and juveniles in 

 some regions, data on larvae were generally used for 

 comparisons because they were more widely available. 

 To assess the impact of particular scientists on the 

 availability of early life history information on fish 

 for a geographic region, we developed a key author 

 index based on references in Moser et al. (1984). 

 Moser et al. (1984) summarized available early life 

 history information for all fishes, so its bibliography 

 provides an indicator of the contributions of individu- 

 als up to about 1982. Key authors were identified as 

 having four or more publications describing the early 

 life history of marine fishes, or as having published 

 a regional compilation of early life history informa- 

 tion. The key author index was calculated by divid- 

 ing the number of publications by key authors by 

 the number of species in a region. Since our purpose 

 here was to indicate the relative amount of research 

 on larval fish taxonomy in various regions, the num- 

 ber of publications was tabulated rather than the 

 number of taxa described. To give a historical per- 

 spective, this index was calculated separately for 

 papers published before and after 1950; 1950 was 

 chosen arbitrarily but coincides roughly with in- 

 creased worldwide harvest of fish following World 

 War II (the world fish catch doubled between 1952 

 and 1965 [Schaefer and Alverson, 1968]). In the Dis- 



cussion section we also refer to work done before and 

 after 1900 (as did Ahlstrom and Moser [1981]) to 

 highlight the roots of ichthyoplankton research since 

 the International Council for the Exploration of the 

 Sea was founded in 1898 and since it began field work 

 on fish eggs and larvae in 1901. 



To investigate the relationship between commer- 

 cial fishing activity and the status of early life his- 

 tory information on a regional basis, we compiled 

 regional commerical catch data (Fig. 1) for 10-year 

 intervals between 1938 and 1988 (Food and Agricul- 

 ture Organization [FAO] 1965, 1974, 1979, 1984, 

 1991, 1992). The first year that such statistics were 

 available was 1938; so compiling data in 10-year 

 increments should document changes in the regional 

 contribution to the world catch which could be re- 

 lated to changes in early life history information. The 

 reported catches include organisms other than ma- 

 rine fish (e.g. molluscs, crustaceans, and seaweeds), 

 but they are a rather uniform fraction of the total 

 catch, and marine fish represent more than 80% of 

 the total catch. Regional catches in 1938 and 1948 

 were averaged to represent conditions before 1950, 

 and regional catches in 1958, 1968, 1978, and 1988 

 were averaged to represent conditions after 1950. The 

 three Antarctic regions (48, 58, 88) used by FAO were 

 combined for our analysis. Catches in the Indian 

 Ocean (51, 57), east central Pacific (77), and west 

 central Pacific (71) were combined to be comparable 

 to the Indo-Pacific region considered by Leis and 

 Rennisl 1983) and Leis and Trnski (1989), although 

 the FAO areas included temperate waters not in- 

 cluded in Leis and Rennis ( 1983) and Leis and Trnski 

 ( 1989). Other FAO regions do not correspond exactly 

 to the regions included in early life history guides 

 (Fig. 1), but at the level of resolution used here such 

 differences are probably insignificant. 



To indicate families with the greatest need for ad- 

 ditional larval fish taxonomic research, we calculated 

 the ratio of the number of species for which larvae 

 had been described over the number of species 

 present by family for the nine geographic regions for 

 which data were available. It was not possible to cal- 

 culate this ratio with the data in Aboussouan ( 1989) 

 or Okiyama ( 1988). Among those above the median 

 of this ratio, up to 10 per region, families in each 

 region for which this ratio was >0.5, were then ranked 

 on the basis of the number of species they contained. 



Results 



On a worldwide basis, Richards ( 1985 ) concluded that 

 20,423 fish species were included in the material 

 summarized in Moser et al. ( 1984 ). Of these species, 



