ably from the Antarctic, is the northernmost Pacific sector record of this 

 species. A small number of collected specimens of birds yielded stomach 

 content information, ectoparasites and tissue samples for pesticide and 

 heavy metal analysis. 



Preliminary results of studies of sedimentation, macrobenthic popula- 

 tion and trace transition metal chemistry of sea water of the east central 

 Chukchi Sea are described. Notable vertical variations in the texture of 

 the core sediments are observed. Beach sediments consist of w^ell rounded 

 moderately well to very poorly sorted sandy gravels with bi- to polymodal 

 size distributions; their texture suggests a complex depositional history. 

 Near-shore sediments are primarily sandy muds with occasional presence 

 of ice-rafted ( ?) gravels. Distributions of clay minerals suggest that 

 chlorite has its source in the adjacent land whereas smectite is most 

 probably transported from the Chirikov Basin. Comparison of the data 

 of this study with those of Naidu et al. (1971) shows significant differences 

 in the relative abundances of clay minerals in the east central Chukchi 

 Sea and the continguous western Beaufort Sea. A general increase in Na* 

 with core depth in the interstitial waters is attributed to the decreased 

 intake of it by sediments as a result of decreased clay content. However, a 

 general increase in K+ with depth is believed to be due to greater dissolution 

 of feldspar and/or decreased adsorption by clays. A net decrease in Ca"^* 

 and Mg++ with depth is probably related to the increased dolomite precipita- 

 tion at greater depths. Post-depositional reduction and upward migration 

 of manganese is attributed to an increase in Mn** toward the core top. 

 The concentrations of Cu and Co in the overlying waters are slightly 

 higher than the averages cited in sea water and are ascribed to local supply 

 of these metals from the adjoining hinterland. However, Ni and Zn con- 

 centrations are lower compared to those generally observed in sea water. 



Sixty-two categories (species and life history stages) of zooplankton 

 were identified from 77 vertical net tows (39 stations) from the eastern 

 Chukchi Sea, September 29-October 17, 1970. Species at each station 

 varied from 5 to 29. Numbers of calanoid copepods varied from 27 to 3146 

 per 100 m^ of water. Data are summarized in two tables and three charts. 



Fish were collected on 20 stations with a 6-foot Isaacs-Kidd midwater 

 trawl and on one station with a 10-foot, shrimp try net. Lists of species 

 captured are presented. 



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 republication in whole or in part or otherwise, that the product has been 

 endorsed, authorized, or approved by the Coast Guard. 



IV 



