A major study of Australian dolphin populations has revealed the need for greater conservation and policy efforts to maintain adaptive diversity and connectivity.
A first-of-its-kind census aimed at helping to safeguard the future of Australia’s dolphin populations amid changes triggered by global warming has raised key conservation implications.
The study of Delphinus delphis along a 3,000 km stretch of the continent’s southern coast has revealed the need for increased efforts to preserve adaptive DNA diversity and connectivity.
The researchers say this will support long-term gene flow and evolutionary form during ongoing habitat changes, including ocean conditions affected by climate change and human activity.
Andrea Barcelo, a biologist at Flinders University, says high levels of genomic variation may play an important role in the survival of common dolphins and other species.
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“How the environment affects the DNA diversity of marine populations can help in their management and in predicting how they may cope with climate change and other anthropogenic impacts,” he said. she declared.
The Flinders and Macquarie University scientists say maintaining connectivity between pods may also promote future genomic variation.
“While so many breeding and foraging conditions are still unknown, it is important that managers of our coastal environments consider the importance of DNA diversity,” said the co-author of the study, Professor Luciana Moller.
“This is especially the case when key environmental conditions such as water temperature, salinity and food sources change.”
The adaptive divergence of over 200 dolphins studied showed five populations from Western Australia to Victoria and compared this with key environmental conditions and food supplies available to fish fed by ocean upwellings and seasonal circulations.
Genomic variation in dolphins off the southern coast of Western Australia was associated with local currents, while those at continental shelf break sites were affected by fluctuations in primary productivity and sea surface temperatures.
In contrast, genomic differentiation between pods from protected coastal habitats and more closed embayment areas was primarily related to fluctuations in local environmental salinity and temperatures.
The various seascape assessments have identified candidate genes for future comparative studies on common dolphins and potentially other delphinid species that share similar dynamic environments around the world.