deposit their eggs on the main spawning 

 grounds south of Point Conception. This north 

 and south movement seemingly is a feeding and 

 spawning migration: northward during the 

 spring and summer, when the sardine is feed- 

 ing and storing up fat, and southward during 

 the fall and winter with the sardine still feeding 

 and the sex products maturing preparatory to 

 another spawning in southern waters." 



In support of this general theory Clark 

 (1935:6) states: 



"The evidence to substantiate these con- 

 clusions about the sardine movements is: the 

 apparent homogeneity of the population along 

 the entire coast (Hubbs, 1925; Clark, F.N., 

 1931; Hart, 1933.2) the greater abundance of 

 smaller, younger fish in the south than in the 

 north as shown by the bait and quarter -oil fish- 

 eries and the San Pedro and Monterey cannery 

 catches; the occurrence of the largest, oldest 

 fish during the summer in British Columbia, 

 their appearance first at San Francisco in the 

 early winter, then at Monterey and last at San 

 Pedro and San Diego in the late winter (Higgins, 

 1926; Scofield, W.L., 1926.2; Clark, F.N., 

 1930 .2, Hart, 1933 . 1); the maturation of the 

 sex products at approximately the same rate as 

 the southward movement followed by the first 

 appearance of spent fish to the northward 

 (Clark, F.N.. 1934); and the location of the 

 main spawning grounds south of Point Conception 

 (Scofield, E.C., 1934)." 



No further use of morphometric data in 

 attempts to distinguish subpopulations have been 

 included in published reports, although there 

 are references to such studies (Hart, 1934: H68, 

 for example) . 



McHugh (1950 --a doctoral dissertation, 

 of which the parts relating to the sardine have 

 not been published) gives data on the relative 

 head length, predorsal length, preanal length 



seems to have been rather generally overlooked, 

 the two forms are con -specific and the form 

 found off our coast should be known as Sardinops 

 melanesticta caerulea (Girard) . At the moment 

 this seems to be a question to which there can 

 only be a subjective answer, since there is no 

 evidence to indicate that there is any genetic 

 exchange between the two groups . (Of course, 

 as Taranets points out, during previous periods 

 of Arctic warming such gene flow obviously did 

 take place, and presumably, in future periods 

 of Arctic warming would again do so, unless 

 the specific level of divergence has been attained 

 prior to such warming.) 



In a recent monograph of the Clupeidae, 

 Svetovidov (1952) considers the eastern Pacific 

 form to be Sardinops sagax ca erulea (Girard) . 

 Earlier, Whittaker (1932) rejected Hubbs' (1929) 

 erection of Sardinops and concluded, on the 

 basis of anatomical studies, that the differences 

 between Sardina and Sardinops were not of 

 generic rank . 



However, more recent work (to be dis- 

 cussed below) has shown that such a general 

 explanation can, at the most, be only partially 

 correct and that the true situation may be more 

 complex . 



Morphometric studies: Morphometric 

 data were used by Thompson (1926) in compar- 

 ing the local sardine with Atlantic (European) 

 pilchard. He made no comparison between 

 local samples . 



Similar data were used by Taranets (1937) 

 in comparing sardines from the eastern and 

 western North Pacific.— 



2/ According to Taranets (1937), whose work 



The taxonomic problem of whether or 

 not these two genera are distinct, and the 

 associated nomenclatorial problem, must be de- 

 cided subjectively and has no bearing on this 

 discussion. Similarly, the taxonomic problem 

 of whether the sagax-neopilchardus-ocellata- 

 caerulea - melanosticta complex represents an 

 allopatric group of species or a group of incipient 

 species, and the associated nomenclatorial 

 problem, must, on the basis of present knowledge, 

 be decided subjectively. These questions are, 

 at the moment, not pertinent to the population 

 dynamics of the form inhabiting the northeastern 

 Pacific . Without attempting to answer these 

 taxonomic and nomenclatorial problems and in 

 conformance with general usage in North America, 

 I refer to the local form as Sardinops caerulea. 



109 



