CHENG and SHULENBERGER: DISTRIBUTION AND ABUNDANCE OF HALOBATES 



130* 120* no* _L00* 



30* 



20* 



10* 



10* 



20' 



ROCKA/VAY-13 



130* 



120* 



110* 



100* 



90' 



80" 



70* 



Figure l. — General cruise tracks for the EASTROPAC Investigation showing basic station positions and areas covered during each 

 cruise. Detailed data given in Table 1; exact station positions differ slightly from cruise to cruise. 



tribution patterns, e.g., the eastern tropical 

 Pacific, transition zone, central watermass, 

 warmwater cosmopolite, and equatorial distri- 

 butional patterns found by McGowan (1971, 1974), 

 Reid et al. (1978), and Brinton ( 1979). These pat- 

 terns seem to parallel the general surface circula- 

 tion of central gyres, equatorial zonal flows, and 

 eastern-boundary upwelling areas at the Equator 

 (Sverdrup et al. 1942). NoHalobates spp. is known 

 to occur regularly at high latitudes. 



Halobates micans is clearly a cosmopolitan trop- 

 ical species occurring in all the world's equatorial 

 current regions (Figure 2). Specimens occur at 



latitudes higher than about 40° (lat. 55° S, long. 

 45° W and lat. 52° N, long. 36° W in Figure 2a) only 

 where poleward extensions of strong warm sur- 

 face currents are known (e.g., Gulf Stream and 

 Kuroshio). 



The North and South Pacific central gyres and 

 the South Atlantic central gyre do not appear to 

 contain H. micans in contrast to the North Atlan- 

 tic central gyre (Figure 2). The central North At- 

 lantic is more heavily sampled than any of the 

 other three gyres; however, there are hydrogaphic 

 reasons to believe that the results are valid, inde- 

 pendent of sampling density The Gulf Stream 



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