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Abstract ABUNDANCE AND DIVERSITY OF CEPHALOPODS IN THE VICINITY OF THE ANTARCTIC PENINSULA Michael Vecchione1, Louise Allcock2,
and Uwe Piatkowski3 Studies of vertebrate predators have indicated that cephalopods
are important in Southern Ocean food webs. Although this is particularly
well-known for squids, we remain unable to sample these pelagic
animals adequately. However, fishery-survey methods used under the
Convention for Conservation of Antarctic Marine Living Resources
(CCAMLR) have proved effective for sampling benthic octopods. We
have found that populations of octopods are substantially higher
around Elephant Island than in similar areas nearby. Effective sampling
of this elevated abundance through collaboration with CCAMLR and
the Census of Marine Life programs has allowed us to collect enough
specimens to show that the diversity of this fauna is much higher
than was previously known; where five octopodid species had been
reported, we have found at least 17 species. The high octopod abundance
around Elephant Island was first detected following the cessation
of commercial fishing in the area because of depletion of target
populations. High octopod abundance has persisted for many years
beyond the cessation of fishing, possibly indicating an enduring
shift in the structure of the ecosystem.
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