Australia’s southern right whale (Eubalaena australis) population, once considered a conservation success story, is now showing signs of stagnation, according to a recent study published in Global Change Biology.
Once nearly driven to extinction by commercial whaling in the 1800s, southern right whales began to recover after protections were introduced in the late 20th century. However, new long-term research indicates that this recovery may be faltering along Australia’s southern coastline.
📉 Whale Numbers Stalling After Decades of Growth
Lead author Anne Grundlehner, a postgraduate researcher at the University of Tasmania’s Institute for Marine and Antarctic Studies (IMAS), explained:
“Although southern right whale numbers increased substantially from the 1970s onward, our latest findings suggest that this recovery has recently plateaued—falling far short of pre-whaling levels.”
The research team analyzed 49 years of aerial survey data from 1976 to 2024, covering over 2,000 kilometers of Australia’s southern coast. These surveys, originally started by the late whale researcher John Bannister, revealed a concerning trend: annual whale births began to stagnate around 2016, with overall coastal sightings showing a sharp decline.
🚨 66% Drop in Coastal Whale Sightings (2011–2024)
While mother-calf sightings remain relatively stable, the number of other whales visiting Australian coastal waters has declined by 66% since 2011. This drop could signal a shift in whale behavior or population health.
Grundlehner noted:
“The southwest coast of Australia had one of the best-recovering populations globally. But given signs of slowing birth rates in other regions, we needed to assess how well our population was truly recovering—and the results are worrying.”
🐋 Southern Right Whales: Key Facts
- Species name: Eubalaena australis
- Status: Endangered (in Australian waters)
- Habitat: Migratory; coastal waters of Australia, New Zealand, South America, South Africa
- Breeding Grounds: Sheltered bays and shallow waters—crucial for calving and nursing
🌊 What’s Causing the Recovery Stagnation?
IMAS researcher and co-author Associate Professor Stuart Corney emphasized that southern right whales are still far from pre-whaling numbers, making it urgent to identify the reasons for their halted growth.
“We don’t yet fully understand why this slowdown is happening. However, changes in the Southern Ocean ecosystem—largely due to historical whale removals—could be a major factor.”
Grundlehner added:
“Despite the end of commercial whaling, today’s marine ecosystem may not be capable of supporting large populations like in the past. Climate change, ocean warming, and other human-induced impacts could be placing additional stress on whale habitats.”
🔍 More Research Needed to Guide Conservation Efforts
As climate change continues to reshape marine environments, ongoing monitoring and adaptive conservation strategies will be essential to protect southern right whales in Australian waters.
The full research paper, titled “The End of an Era? Trends in Abundance and Reproduction of Australian Southern Right Whales (Eubalaena australis) Suggest Failure to Re‐Establish Pre‐Whaling Population Size”, is available in Global Change Biology (2025).
DOI: 10.1111/gcb.70218