Differences in sexual maturity and related characteristics between populations of thorny skate (Raja radiata) in the northwest Atlantic
Sexual maturity of the thorny skate (Raja radiata) occurs at relatively small sizes off northern Iceland and West Greenland, off Baffin Island and Labrador, on the Northeast Newfoundland Shelf and in the Gulf of S1. Lawrence, and at considerably larger sizes on the Grand Bank and 81. Pierre Bank. In...
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Format: | Text |
Language: | English |
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1987
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Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.606.499 http://journal.nafo.int/j07/templeman4.pdf |
Summary: | Sexual maturity of the thorny skate (Raja radiata) occurs at relatively small sizes off northern Iceland and West Greenland, off Baffin Island and Labrador, on the Northeast Newfoundland Shelf and in the Gulf of S1. Lawrence, and at considerably larger sizes on the Grand Bank and 81. Pierre Bank. In areas with sexual maturity at a small length, the maximum fish lengths weretypicallysmall, and in areas with sexual maturity only at much greater lengths, the maximum lengths were considerably larger. The largest thorny skate was a 104-cm male from the southern Grand Bank. The lengths at sexual maturity and the maximum lengths for males were greater than those for females. One hermaphrodite was noted. There was a higher maximal number of rows of alar spines in areas with sexual maturity at a larger size. From the great differences between areas in length at sexual maturity, it is concluded that no large-scale migrations of thorny skate occurred between these areas. |
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