Genomics identifies koala populations at risk across eastern Australia

Area of Science:

• Conservation genomics
• Wildlife population studies
• Australian marsupial research

Background:

• Koalas, iconic Australian marsupials, are endangered due to disease, habitat loss, and mega-fires.
• Climate change and habitat clearing increase the vulnerability of koala populations to decline and isolation.
• Small, isolated populations risk inbreeding, reduced genomic diversity, and loss of adaptive potential.

Purpose of the Study:

• To characterize the current genomic landscape of koalas across eastern Australia.
• To identify populations with low genomic diversity and high inbreeding.
• To assess the genomic vulnerability of koalas to future climate change.

Main Methods:

• Utilized data from The Koala Genome Survey, a government initiative for baseline genomic data.
• Analyzed genomic data to measure runs of homozygosity, indicating inbreeding and low diversity.
• Assessed genomic vulnerability to projected future climate scenarios.

Main Results:

• Identified koala populations with low genomic diversity and high inbreeding in coastal southeast Queensland, northern/mid-coast New South Wales, southern New South Wales, and Victoria.
• Northern koala populations exhibit higher genomic vulnerability to extreme climate changes.
• Habitat destruction from development, especially linear infrastructure, is driving population isolation and genomic erosion.

Conclusions:

• Habitat protection and the establishment of wildlife corridors are essential for maintaining koala genomic diversity.
• Active management may be necessary for highly isolated populations to improve genomic diversity.
• Reversing genomic isolation must be a priority for koala conservation to ensure long-term survival.