Rig (Mustelus lenticulatus) were tagged around the South Island and south‐west North Island to determine movement patterns and stock distributions. Recaptured females travelled further than males, and off the east coast of the South Island mature females travelled further than immature females. No seasonal differences were found in the direction or distance travelled. The greatest displacement velocity recorded for a tagged rig was 21 km/day, but few travelled faster than 7 km/day. Over half the recaptured rig travelled > 50 km, and 52% of the females travelled > 200 km. The greatest recorded movement was 1159 km. Male stocks have a small range and may overlap considerably with each other. Separate stocks of females exist on the east and west coasts of the South Island, but some overlap occurs. The relationship between the annual movement patterns of rig, and the annual reproductive cycle is discussed. Available data are insufficient to determine why rig aggregate annually in shallow coastal waters.
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Malcolm P. Francis (1988) studied this question.
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