Genetic bottlenecks in Pristis sawfishes in northern Australian waters

Endangered species research

David L. Morgan^2¹  Nicole M. Phillips^1³  Annmarie Fearing^1⁴ 

[1] Fish Health Unit, Centre for Fish &Fisheries Research, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia 6150, Australia^2;Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, Mississippi 39406, USA^1;Freshwater Fish Group &

关键词: Founder effect;    Pristis clavata;    Pristis zijsron;    Pristis pristis;   

DOI  :  10.3354/esr00815

学科分类：动物科学

来源: Inter-Research

【 摘 要 】

Northern Australia has been identified as the last stronghold for the dwarf sawfish Pristis clavata, green sawfish P. zijsron, and largetooth sawfish P. pristis, making these populations key in global conservation efforts for each species. This research assesses the levels of genetic diversity in these 3 sawfishes in Australian waters, testing for the presence of population bottlenecks using data at microsatellite loci. Levels of observed heterozygosity in each species from the west coast of Australia and the north-eastern Gulf of Carpentaria were generally high. M ratio tests suggest that assemblages of P. zijsron and P. pristis on the west coast and P. clavata and P. zijsron in the Gulf of Carpentaria may have experienced population bottlenecks. The bottlenecks are especially pronounced in P. zijsron populations and in P. clavata from the Gulf of Carpentaria. Demographic analyses, based on mtDNA data, indicate relatively recent (evolutionarily) range expansions in Pristis sawfishes in northern Australian waters, which could account for the population bottlenecks. A more recent range expansion in each of P. clavata and P. zijsron, as evidenced by more recent population divergence and more recent/higher rates of historic maternal gene flow, could account for the more pronounced bottlenecks in these species when compared to P. pristis. Given that Pristis sawfishes in Australian waters have experienced population bottlenecks, whether they be historic, contemporary or both, the preservation of remaining genetic diversity should be a high conservation priority.

【 授权许可】

Unknown