University Of Tasmania
142051 - Bacterial epibiont communities of panmictic Antarctic krill_OA.pdf (663.95 kB)

Bacterial epibiont communities of panmictic Antarctic krill are spatially structured

Download (663.95 kB)
journal contribution
posted on 2023-05-20, 19:49 authored by Laurence ClarkeLaurence Clarke, Suter, L, King, R, Bissett, A, Sophie BestleySophie Bestley, Deagle, BE
Antarctic krill (Euphausia superba) are amongst the most abundant animals on Earth, with a circumpolar distribution in the Southern Ocean. Genetic and genomic studies have failed to detect any population structure for the species, suggesting a single panmictic population. However, the hyper‐abundance of krill slows the rate of genetic differentiation, masking potential underlying structure. Here we use high‐throughput sequencing of bacterial 16S rRNA genes to show that krill bacterial epibiont communities exhibit spatial structuring, driven mainly by distance rather than environmental factors, especially for strongly krill‐associated bacteria. Estimating the ecological processes driving bacterial community turnover indicated this was driven by bacterial dispersal limitation increasing with geographic distance. Furthermore, divergent epibiont communities generated from a single krill swarm split between aquarium tanks under near identical conditions suggests physical isolation in itself can cause krill‐associated bacterial communities to diverge. Our findings show that Antarctic krill‐associated bacterial communities are geographically structured, in direct contrast with the lack of structure observed for krill genetic and genomic data.


Australian Research Council


Publication title

Molecular Ecology










Institute for Marine and Antarctic Studies


Blackwell Publishing Ltd

Place of publication

9600 Garsington Rd, Oxford, England, Oxon, Ox4 2Dg

Rights statement

Copyright 2020 John Wiley & Sons Ltd.

Repository Status

  • Open

Socio-economic Objectives

Assessment and management of Antarctic and Southern Ocean ecosystems; Biodiversity in Antarctic and Southern Ocean environments