KENNEY and WINN: CETACEAN HIGH-USE HABITATS 



44° - 



42° - 



40° - 



38' 



36< 



34 c 



Figure 1— Plot of 10-minute blocks with total cetacean biomass per unit effort values in the 

 top 10% of all blocks. GM = Gulf of Maine; GB = Georges Bank; NC = Northeast Channel; 

 JL = Jeffreys Ledge; SB = Stellwagen Bank; GS = Great South Channel. 



is a general pattern of reduced utilization during the 

 fall and winter. 



Figure 3 shows the whole-year patterns of high 

 habitat usage for the four subsets of the total ceta- 

 cean community. The pattern for endangered species 

 shows only slight differences from the total com- 

 munity pattern seen in Figure 1. Differences from 

 the total community pattern become somewhat 

 greater in the piscivorous component. The intensity 

 of utilization along the shelf edge is less, but there 

 appears an area or areas of high use at midshelf east 

 of the Chesapeake Bay region. The planktivorous 

 component shows a distinctive pattern. There are 

 only scattered high-use blocks in the southern half 

 of the area. In the northern half of the area, the pat- 

 tern is similar to those for the entire community, en- 

 dangered species, or piscivores, except that there are 

 more high-use blocks in the central portion of the 

 Gulf of Maine and on the southern part of Georges 



Bank. The teuthivorous component shows the most 

 distinct pattern, with a dense concentration of high- 

 use blocks along the shelf edge in the southern half 

 of the area and a less dense concentration along the 

 more northern shelf edge and in the vicinity of the 

 Northeast Channel. 



Finally, Figure 4 presents the overall composite 

 pattern of high-use areas, plotting those 10-minute 

 blocks with Habitat Use Index values in the upper 

 5%, 10%, and 20% of all blocks sampled. Of the total 

 of 1,476 blocks surveyed, 889 had index values of 

 and 587 were 1 or greater. The maximum index value 

 was 49 for a block located at the northern end of 

 Stellwagen Bank. Table 4 lists the blocks in the up- 

 per 1% of the distribution, showing their locations. 

 Of those 16 blocks, 13 are in the western Gulf of 

 Maine between the Great South Channel and Jef- 

 freys Ledge. This area shows the densest concentra- 

 tion of high-use blocks in Figure 4. The secondary 



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