McEACHRAN and MUSICK: DISTRIBUTION AND RELATIVE ABUNDANCE OF SKATES 



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Figure 8. — Index of abundance (geometric mean) of Raja erinacea captured in each subarea during 

 winter 1969 within temperature intervals of 1°C. See Figure 3 for explanation of fractions and 

 whole numbers. 



the southern section of the mid- Atlantic Bight it 

 was usually caught in the lower part of the area's 

 temperature range, and on the Nova Scotian 

 shelf in the upper part of the temperature range. 

 Along the inshore fringe of its range the species 

 moves onshore and offshore with seasonal tem- 

 perature changes as stated by Bigelow and 

 Schroeder (1953); Merriman et al. (1953); Fitz 

 and Daiber (1963); Richards (1963); Schaefer 

 (1967); and Tyler (1971, 1972). Raja erinacea 

 also moves north and south with seasonal tem- 

 perature changes along the southern fringe of its 

 range. Contrary to Bigelow and Schroeder (1953) 

 and Leim and Scott (1966), R. erinacea probably 

 does not regularly occur off Nova Scotia north 

 of LaHave Bank, and it may be entirely absent 

 in the Gulf of St. Lawrence (McEachran 1973). 



Raja ocellata 



Raja ocellata was frequently taken in the Gulf 

 of St. Lawrence, off northeastern Nova Scotia, 

 and the offshore banks of Banquereau, Sable 

 Island, and Western Bank. It was second to 

 R. erinacea in abundance on Georges Bank and 

 in the northern section of the mid- Atlantic Bight 

 (Figure 11). Raja ocellata was much more 

 abundant in the southern section of the mid- 

 Atlantic Bight during the winter than during 

 the remainder of the year. This species was most 

 frequently captured in water shallower than 

 111 m, but was occasionally caught deeper than 

 the maximum depth of 110 m recorded by Bigelow 

 and Schroeder (1953). In the Gulf of Maine it 

 was taken at 205 m, and in the Gulf of St. 



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