McEACHRAN and MUSICK: DISTRIBUTION AND RELATIVE ABUNDANCE OF SKATES 



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TEMPERATURE 



Figure 21. — Index of abundance (geometric mean) of Raja radiata captured in each subarea during summer 1969 within 

 temperature intervals of 1°C. See Figure 3 for explanation of fractions and whole numbers. 



18 to 996 m at - 1.4° to 14°C but is most abundant 

 below 110 m at 2° to 10°C. 



Raja erinacea and R. ocellata are sympatric 

 species with very similar habitat requirements. 

 Raja ocellata has slightly lower temperature 

 preferences than R. erinacea and occurs farther 

 to the north than the latter. Raja senta and 

 R. radiata are sympatric species; R. radiata has 

 wider temperature range and is more widespread 

 than R. senta. 



ACKNOWLEDGMENTS 



We are very grateful to the Northeast Fish- 

 eries Center Woods Hole Laboratory, NMFS, 



NOAA; the Fisheries Research Board of Canada 

 Biological Station at St. Andrews, New Bruns- 

 wick; and the Southeast Fisheries Center Pas- 

 cagoula Laboratory, NMFS, NOAA for furnishing 

 data for this study. The two former institutions 

 also permitted the senior author to take part in 

 their groundfish surveys. 



The Northeast Fisheries Center Woods Hole 

 Laboratory, NMFS, NOAA gave access to their 

 computer programs and computer facilities to 

 summarize data. The VIMS survey of Chesapeake 

 Bight was supported in part by the NMFS 

 under P.L. 88-309, Project 3-5-D, Jackson Davis, 

 Principle Investigator. 



Special thanks is given to Marvin Grosslein 

 of the Northeast Fisheries Center Woods Hole 



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