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Data on the location, date, sea temperature, and turtle size for 98 small (

A short review shows that in cold, arctic regions of the North Atlantic positive relationships are generally observed between cod recruitment and water temperatures whilst negative relationships are observed in warm-temperate regions. According to this relationship, cod recruitment in the Irish Sea should be negat~vely related to sea temperature. Using 3 ~ndependent sources of longterm temperature records we test this hypothesis and show a highly significant connection between the recruitment of cod and temperature signals. We suggest that this relationship should be taken into account, in addition to spawning stock biornass, in any future attempt at understanding cod recruitment in this area.

Ragworms Nereis diversicolor live in burrows which, if deeper than 5 to 10 cm, offer a saferefuge from most of their predators. Burrow depth must be ca 15 cm before they live out of reach of all predators. Burrow depth increases with body slze, levelling off at ca 15 cm, when the depth refuge is reached. Worms live at greater depths in sand than In mud, but this effect disappears if worms with identical body condition (expressed as deviation from mean body weight for a given body length) are compared. Seasonal variation in burrow depth is correlated with sea temperature and to a lesser extent with day length and body condition. Feeding worms are present near or at the surface. Fllter feeding occurs in the first 2 h after exposure (at least if a water film still remains at the surface) and surface feeding begins after that. The total time spent at the surface does not exceed an average of 50 s per tidal cycle. Feeding must be an extremely risky activity, because predators readily catch mostN. diversicolor while present near or at the surface.

Etude menee au Cap de Bonne Esperance a l'aide de l'analyse de grappe des donnees, pour 310 especes, sur 12 cotes rocheuses