By Tupou Vaipulu Jr.

The lack of recovery of the marine ecosystem around the area of the  Hunga Tonga-Hunga Ha’apai (HTHH) volcano, surprised an international team of scientists who have been researching the area for several weeks.

“We expected to see more biological species in the water column, as well as on the sea floor but that was not the case,” said Chief Scientist Dr. Rebecca Carey, on board the RV Investigator, back in Nuku'alofa this week.

The team found out that the marine life around HTHH is recovering only very slowly, three years after the 2022 eruption of Tonga’s underwater Hunga Volcano - the largest volcanic eruption recorded in over a century - which devastated the marine ecosystems within 100 kilometres of the site.

Dr Carey led a team of researchers from Australia on a 54 day voyage [2] to conduct the study in the waters around the volcano. 

Dr. Carey said that, “Three years later we’ve come back, and we’ve surveyed the seafloor and found that the microscopic fauna and the species – they are still not really recovering."

However, Dr. Carey said they discovered microscopic fauna called foraminifera (tiny, single-celled organisms with a shell) within the volcanic sediment on the seafloor.

“If those foraminiferas can flourish, it will bring in the larger biological species like fishes and squids.”

Dr. Carey said that they found more nutrients within the summit of the volcano, indicating that life is flourishing a little more within the volcano rather than outside of it.

“That’s what we expected, and it was nice to see that.”

Other Pacific Nations with underwater volcanoes are now interested in their research, to inform the possible risks of these volcanoes.

Dr. Carey and her team will continue their research using samples they have collected from the volcano and seabed to determine other objectives including the impact of the eruption on the Tonga Optic Fiber Cable and the cause of the eruption.

The team departed Tongatapu on the Research Vessel (RV) Investigator on Tuesday, 23 September.

The voyage brrought together 40 researchers and technical staff from Australia, Tonga, Fiji, New Zealand, the UK, and the US, who will carry out more than 120 scientific operations in and around the underwater volcano. Dr Carey from the University of Tasmania’s Centre for Ore Deposit and Earth Sciences (CODES) said the “ground zero” underwater scene produced by the blast offered a unique opportunity to study the recovery of deep-sea ecosystems.

See also:

https://matangitonga.to/2025/09/16/life-erupting-hunga-volcanic-mud-soup [3]