Antarctic seafloor at risk as ship anchors crush unique marine life: study

Canada Standard

09-06-2025

WELLINGTON, June 9 (Xinhua) -- Ship anchors are causing significant damage to the fragile Antarctic seafloor, crushing unique marine life and leaving long-lasting scars, a new study revealed on Monday.
Video footage from 36 Antarctic Peninsula and South Georgia Island sites shows that ship anchoring leaves areas nearly lifeless, with crushed sponges and scarred seafloor, while nearby undisturbed zones remain biodiverse, according to scientists from New Zealand, Canada and the United States.
"Anchoring impacts are understudied and underestimated globally. It's so important to recognize and mitigate the impacts across all industries and limit planned anchoring," said the study's co-author Sally Watson, a marine geophysicist at New Zealand's National Institute of Water and Atmospheric Research.
Using underwater cameras, the research found that the problem is growing as shrinking sea ice opens up more of Antarctica to cruise, research, fishing, and private vessels, the scientists said, adding that anchor damage is almost entirely unregulated in Antarctica, despite strict conservation rules for other activities.
During the 2022-2023 Antarctic summer, at least 195 ships anchored in Antarctic waters, likely underestimating the true number, said the study published in Frontiers in Conservation Science.
Footage revealed crushed ancient sponges and a lack of benthic animals in disturbed areas, while undamaged sites were rich in unique, slow-growing species highly vulnerable to such impacts.
While research on anchor impacts is increasing in tropical reefs, Watson highlighted a major knowledge gap in Antarctica. Each vessel anchoring in 30-40 meters of water could disturb at least 1,600 meters of seabed, not accounting for additional damage from chains dragging if ships move, she said.
Scientists caution that recovery from seafloor damage in Antarctica could take decades or longer, as similar harm in warmer regions has persisted for over ten years.
The loss of sponges and other seafloor life disrupts key ecosystem functions like water filtration, carbon storage, and habitat provision, threatening the broader Antarctic food web, including species such as penguins and seals that draw tourists, said the study's lead author, Matthew Mulrennan, who founded the California-based ocean exploration and conservation nonprofit KOLOSSAL.
"Anchoring is likely the most overlooked ocean conservation issue in terms of global seafloor disruption; it is on par with the damages from bottom trawling," Mulrennan said.