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    Summary of Ross Sea skate tagging programme results

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    Numéro du document:
    WG-FSA-06/32
    Auteur(s):
    S.L. Ballara, A. Dunn and M.P. Francis (New Zealand)
    Point(s) de l'ordre du jour
    Résumé

    Over 9,000 skates have been tagged and released in the Ross Sea over a period of seven years, and 47 (0.5%) have been recaptured. The recapture of tagged Amblyraja georgiana after up to four years at liberty shows that some skates survive and recover from being hauled out of depths of around 1,000 m and tagged. In-water tagging greatly reduces the incidence of broken jaws in skates, and probably increases the survival of released animals. Unfortunately, this means that length at release can not be determined, so no useful data were gathered for estimating skate growth rates. Amblyraja georgiana moved very little, even after four years at liberty. There was no movement between SSRUs, and the maximum distance travelled was less than 70 km. The distance travelled did not increase with period at liberty for skates at liberty more than nine months. It appears that this species makes only small-scale movements along depth contours.