Environment, adaptation and evolution: scallop ecology across the latitudinal gradient

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Body size, geographical distribution and biomass make Adamussium colbecki (Smith, 1902) one of the most conspicuous bivalve species in the Antarctic. Based on samples collected in austral summer 1999/2000 in Terra Nova Bay, the annual formation of shell growth bands visible on x-ray photographs was verified by stable isotope analysis. A general von Bertalanffy growth function was fitted to size-at-age data of 25 individuals (H?= 108.86 mm, K= 0.114 y-1, t0= -0.367, D= 1.284). Somatic production calculated from mass-specific growth rates was 234.6 kJ m-2 y-1. Gonadal productivity amounted to 70.92 kJ m-2 y-1. Annual somatic and gonad production-tobiomass ratios (P/B) were 0.199 and 0.052, respectively. According to its consumption and production A. colbecki is likely to play a significant role in the trophic web of Terra Nova Bay.