Iceberg scour and shell damage in the Antarctic bivalve Laternula elliptica

PLoS One. 2012;7(9):e46341. doi: 10.1371/journal.pone.0046341. Epub 2012 Sep 28.

Abstract

We document differences in shell damage and shell thickness in a bivalve mollusc (Laternula elliptica) from seven sites around Antarctica with differing exposures to ice movement. These range from 60% of the sea bed impacted by ice per year (Hangar Cove, Antarctic Peninsula) to those protected by virtually permanent sea ice cover (McMurdo Sound). Patterns of shell damage consistent with blunt force trauma were observed in populations where ice scour frequently occurs; damage repair frequencies and the thickness of shells correlated positively with the frequency of iceberg scour at the different sites with the highest repair rates and thicker shells at Hangar Cove (74.2% of animals damaged) compared to the other less impacted sites (less than 10% at McMurdo Sound). Genetic analysis of population structure using Amplified Fragment Length Polymorphisms (AFLPs) revealed no genetic differences between the two sites showing the greatest difference in shell morphology and repair rates. Taken together, our results suggest that L. elliptica exhibits considerable phenotypic plasticity in response to geographic variation in physical disturbance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amplified Fragment Length Polymorphism Analysis
  • Animal Shells / anatomy & histology*
  • Animal Shells / injuries*
  • Animals
  • Antarctic Regions
  • Bivalvia / physiology*
  • Ecosystem
  • Ice Cover*
  • Oceans and Seas
  • Population Dynamics

Grant support

This work was not part of any specific grant but as part of a general research programme between the University of Cambridge and the British Antarctic Survey. SAM, LSP and MSC were supported by the British Antarctic Survey Polar Science for Planet Earth Progamme, Adaptation and Physiology Work Package. JH was supported by a Natural Environment Research Council (NERC) British Antarctic Survey (BAS) Strategic Alliance Fellowship. During the sampling period of the Jubany specimens EP was supported by a PhD scholarship from the University of Bremen. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.