SYDNEY, July 18 (Xinhua) -- Shrinking Antarctic sea ice is making humpback whales migrate south about three weeks earlier than 21 years ago, Australian research revealed recently.
According to a long-term study by Australia's University of Queensland (UQ), researchers attributed this shift to a warming Southern Ocean and declining Antarctic sea ice, which may be impacting the whales' summer feeding.
The peak of the humpback whale's southern migration down the east Australian coast has shifted from early October in 2003 to mid-September in 2024, with notably earlier migrations seen since 2021, said UQ Associate Professor Rebecca Dunlop, the research lead.
Less Antarctic sea ice means less algae, crucial food for krill, Dunlop said, adding, "Less available krill prior to the migration could be forcing the whales back to the feeding grounds earlier."
Eastern Australia's humpback whale population has rebounded from 300 in the 1960s to about 40,000, but rising ocean temperatures due to climate change leading to shrinking sea ice have disrupted whales' once-consistent migration timing, also seen off Western Australia and South America, according to the findings detailed in Scientific Reports published by Nature.
Further studies are underway to determine whether the timing of the northward migration is also changing. ■
