During October–November 2025, the National Environment Service (NES) carried out ant surveillance across Suwarrow National Park, collecting samples from 12 motu around the atoll. The work focused particularly on Anchorage Island, the main arrival point for visitors and vessels to Suwarrow and therefore the highest biosecurity risk area for potential species introductions.
Using bait stations made from simple attractants like peanut butter and jam, NES staff collected 29 samples which were carefully preserved and sent to the Ministry of Agriculture (MOA) Biosecurity Laboratory for identification.
Laboratory analysis confirmed six ant species currently present on Suwarrow. While six species were recorded, two Nylanderia bourbonica and Solenopsis geminata dominated the samples, accounting for more than 80% of detections. In addition, Tetramorium bicarinatum was identified as a newly recorded species for Suwarrow, contributing to the overall species diversity.
Species identifications were verified with technical support from MPI’s Plant Health and Environment Laboratory. While none of the species rank among the top five invasive ants in the Pacific, they are still considered invasive on Suwarrow, highlighting the importance of continued surveillance.The findings also provide an important baseline that will help update the Cook Islands Biodiversity Database (CIBED) and guide future monitoring and invasive species management across the atoll.
This work highlights the value of strong collaboration between the NES and the MOA, combining field monitoring, laboratory diagnostics, and international expertise to strengthen the Cook Islands’ biosecurity protection.
