2016_Abatus.pdf (1.19 MB)
Population structure and long-term decline in three species of heart urchins Abatus spp. near-shore in the Vestfold Hills region, East Antarctica
journal contribution
posted on 2023-05-18, 17:54 authored by Carrea, C, Christopher BurridgeChristopher Burridge, King, CK, Miller, KJPatterns of fine-scale spatial population structure in Antarctic benthic species are poorly understood. There is a high proportion of brooding species in the Antarctic benthos, and a brooding life history strategy is expected to restrict their dispersal abilities and therefore foster population structure. Additionally, genetic structuring of populations can preserve signals of historic processes (such as Pleistocene glaciations) on species distributions and abundances. We developed a set of seven microsatellite markers to examine population genetic variation and infer the demographic history of three sympatric Antarctic sea urchin species from the order Spatangoida (Abatus ingens, A. shackletoni and A. philippii), all with brooding life history strategies. Samples were collected at five sites separated by up to 5 km, in the near-shore area surrounding Davis Station in the Vestfold Hills area of the Australian Antarctic Territory. We found evidence of a long-term population decline in all three species, and the estimated timing of the decline precedes anthropogenic activities and is compatible with long-term climate variability. Two genetic clusters in A. ingens and A. shackletoni suggest secondary contact after population differentiation in glacial refugia. Life history is not a good predictor of fine-scale population structure in these species, with gene flow possible at distances of 5 km. Finally, no evidence was found for a potential impact of pollution from Davis Station on genetic variation. The reduced effective population size observed for these Antarctic benthic species highlights their fragility and the need for conservation concern.
Funding
Department of Environment and Energy (Cwth)
History
Publication title
Marine Ecology - Progress SeriesVolume
545Pagination
227-238ISSN
0171-8630Department/School
School of Natural SciencesPublisher
Inter-ResearchPlace of publication
Nordbunte 23, Oldendorf Luhe, Germany, D-21385Rights statement
Copyright 2016 The authors. Licensed under Creative Commons Attribution 3.0 Unported (CC BY 3.0) http://creativecommons.org/licenses/by/3.0/Repository Status
- Open