Rowley Shoals – A remote marine park off Australia’s northwestern coast has recorded a steep decline in sea cucumber numbers over five years. Overall populations fell by more than half between 2018 and 2023, according to monitoring data from the area. Two species in particular, the pineapple sea cucumber and the hairy blackfish, have vanished from nearly all surveyed sites. The losses point to sustained illegal harvesting in waters where such activity is banned.
Scale of the Recorded Decline
Surveys across multiple sites in the Rowley Shoals documented the drop in a region known for its largely untouched coral reefs. The reduction affected both common and more vulnerable species, leaving some monitoring locations without any individuals of the two most affected types. Researchers tracking the trend described the change as rapid and widespread within the protected zone. The findings cover a period when no legal harvesting was permitted, which narrowed the likely causes to unauthorized activity.
Intercepted Vessels and Estimated Harvest
Australian authorities detained 112 fishing vessels in the Rowley Shoals between 2021 and 2023. Those vessels carried a combined 22 metric tons of sea cucumbers, an amount estimated to represent 33,000 to 45,000 individual animals. Officials noted that the intercepted catch represents only the portion they managed to seize. The true scale of removals is believed to be substantially larger.
Wider Pattern Across Northern and Western Waters
The same pressures appear in other reef systems along Australia’s western and northern coasts. Several researchers tracking the issue reported an increase in illegal activity in recent years, with a noticeable spike during 2024. Fishers have targeted both general sanctuary zones and areas that protect internationally listed species. Demand from markets in China and other East Asian countries, where sea cucumbers serve as a delicacy and ingredient in traditional medicine, continues to drive the trade.
Government Response and Next Steps
In response to the rise in violations, authorities launched Operation LUNAR to strengthen enforcement in the affected regions. The operation focuses on intercepting vessels and protecting the remaining populations in marine parks and sanctuaries. Stakeholders including park managers and fisheries officers now face the task of balancing limited patrol resources against expanding illegal activity. Continued monitoring will determine whether the measures slow the ongoing losses in these remote ecosystems.
