612 



Fishery Bulletin 102(4) 



■Si 3 





 3.2 



"5 2.8 



o 



■o 



2.4 



1.6 J 

 30 



20 



10 



O 



60 100 140 180 



aartdneg Yrre nuelgur Yeea 



Figure 6 



Profiles of elemental ratios, deter- 

 mined with laser ablation ICP-MS, 

 from the nucleus out to a distance 

 of approximately 200 /.mi in the oto- 

 liths of larval and juvenile walleye 

 pollock iTheragra ehaleogramma) 

 collected from the North Bering 

 Sea (A), southeast Bering Sea 

 (O), Bristol Bay (■), Prince Wil- 

 liam Sound lOl, and Yakutat I  >. 

 Individual points are mean (±SE) 

 values grouped at 40-jAm intervals. 



cleus out to a distance of approximately 200 jjm in the 

 walleye pollock otoliths (Fig. 6, Table 6). The univariate 

 test of location, averaged over the individual otolith 

 profiles, was significant for both Sr/Ca and Ba/Ca. We 

 also found significant interactions between profile and 

 location for Mn/Ca, Sr/Ca, and Ba/Ca ratios (Table 6). 

 Manganese values increased from the nucleus to the 

 otolith edge at all locations, indicating that the signifi- 

 cant interaction was generated by the observation that 

 the profile from the North Bering Sea was considerably 

 flatter than profiles from Bristol Bay and southeast 

 Bering Sea. Strontium trajectories were more dynamic; 

 profiles from some locations increased from the nucleus 

 to the edge (Bristol Bay and Prince Williams Sound), 



4.5 



3.5- 



' I 



li'f'Mi 1 



* ft ft 



ft ft ft ft ft ft ft 



z 



CO 



O 



CO 



O 

 O 



* ft 



HHf 



. 



. I 



ft! 



*;**** 



tp 



6 10 14 18 22 26 30 34 38 42 46 50 54 58 



Distance from nucleus (mm x 10' 2 ) 



Figure 7 



Profiles of elemental ratios, determined by using 

 laser ablation ICP-MS. from the nucleus out to a 

 distance of approximately 600 fim in the otoliths of 

 juvenile walleye pollock (Thuragra ehaleogramma) 

 collected from Bristol Bay  and Yakutat i I. 

 Individual points are mean (± SE) values grouped 

 at 40-;/m intervals. 



profiles from other locations decreased (North Bering 

 Sea and Yukatat), and a single location (southeast Ber- 

 ing Sea) showed no obvious trend. Finally, profile varia- 

 tions in Ba/Ca ratios among locations were dominated 

 by a sharp increase in Ba/Ca ratios across the otoliths 

 in the southeast Bering Sea samples. Profiles were ef- 

 fectively horizontal for the other four locations. 



Otoliths in walleye pollock collected from Bristol Bay 

 and Yakutat were significantly larger than those from 

 the other four locations. We were, therefore, able to con- 

 duct extended profiles in these otoliths out to a distance 

 of approximately 600 fim (Fig. 7). After starting at 

 similar values at the nucleus, Mn/Ca and Sr/Ca profiles 

 from the two locations quickly diverged and appeared 

 to vary largely independently over the remaining time 

 periods. The Ba/Ca profiles also appeared to be vary- 

 ing independently between the two locations, although 

 the relative magnitude of differences between the two 

 locations was smaller than for either Mn/Ca or Sr/Ca 

 profiles. 



