There was sufficient evidence to once demonstrate the existence of essentially two major stocks off the British Isles a northerly stock, that migrated between the Irish Sea and Norway, and a southern stock that frequented the English Channel and environs. Today the situation is less readily discernable. These sharks also shoal spatially and temporally by sex, which may again effect the outcome of tagging studies where returns are gathered by commercial fishing. An ovoviviparous species, with 2 to 11 young which are born at a sex ratio of 11. Gestation period is 18-22 months, with females giving birth once every two years.
Females mature after ca.
11 years at 60 to 72cm.