Population dynamics of the ubiquitous Antarctic benthic amphipod Orchomenella franklini and its vulnerability to environmental change

• Published in: Polar Biology
• Main Authors: Baird, HP, Stark, JS
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer-Verlag 2013
• Subjects: Biological Sciences; Ecology; Marine and Estuarine Ecology (incl. Marine Ichthyology); Antarctic; Casey Station; Antarc*; Polar Biology; Sea ice
• Online Access: https://doi.org/10.1007/s00300-012-1246-8; http://ecite.utas.edu.au/89596

Comprehensive ecological research is stilllacking for many of the species that dominate the Antarcticbenthos, preventing an adequate understanding of theirpotential response to environmental change. Here, populationdynamics were explored in one of the most ubiquitousnearshore Antarctic benthic amphipods, Orchomenellafranklini. Sex, reproductive status and body length wererecorded for over 6,000 individuals, sampled from a varietyof locations and times at Casey station in East Antarctica.Several life history traits were revealed for O. franklini thatexemplify adaptations predicted for a polar environment.These include delayed reproduction, extended broodincubation, low fecundity, longevity and seasonal breedinglinked to the summer phytoplankton bloom. There was alsopreliminary evidence of inter-annual and spatial fluctuationsin population structure, potentially reflecting localenvironmental heterogeneity such as sea-ice duration. Theinfluence of both large scale and local environmentalconditions on the ecology of O. franklini provides insightinto the vulnerability of this species to environmentalchange.