In 2015, a submarine volcano in the South Pacific erupted, forming the Hunga Tonga Hunga Ha’apai island. On January 15, 2022, seven years after it formed, the volcano erupted again, obliterating the entire landmass in the largest volcanic explosion of the 21st century.

Within that short time frame a team of scientists led by the University of Colorado Boulder and Cooperative Institute for Research in Environmental Sciences (CIRES) and with the support of the Kingdom of Tonga took the opportunity to study the life that was forming and existing on the island.

The team collected soil samples from the island for analysis. 

Researcher CIRES PhD student Nick Dragone, explained:

“These types of volcanic eruptions happen all over the world, but they don’t usually produce islands. We had an incredibly unique opportunity. No one had ever comprehensively studied the microorganisms on this type of island system at such an early stage before.

“We didn’t see what we were expecting. We thought we’d see organisms you find when a glacier retreats, or cyanobacteria, more typical early colonizer species—but instead we found a unique group of bacteria that metabolize sulfur and atmospheric gases.”

“One of the reasons why we think we see these unique microbes is because of the properties associated with volcanic eruptions: lots of sulfur and hydrogen sulfide gas, which are likely fueling the unique taxa we found.

 “The microbes were most similar to those found in hydrothermal vents, hot springs like Yellowstone, and other volcanic systems. Our best guess is the microbes came from those types of sources.”

When the volcano exploded again and obliterated the island, the area the team was studying went with it.

Acknowledging the cooperation that was needed to make this study possible Nick Dragone said:

“This work brought in so many people from around the world, and we learned so much. We are of course disappointed that the island is gone, but now we have a lot of predictions about what happens when islands form.

“So if something formed again, we would love to go there and collect more data. We would have a game plan of how to study it.”

The expedition required close collaboration with members of the government of the Kingdom of Tonga, who were willing to work with researchers to collect samples from land normally not visited by international guests. Coordination took years of work by collaborators at the Sea Education Association and NASA: a Tongan observer must approve and oversee any sample collection that takes place within the Kingdom.

Noah Fierer, CIRES fellow, professor of ecology and evolutionary biology at CU Boulder added:

“Studying the microbes that first colonize islands provides a glimpse into the earliest stage of ecosystem development – before even plants and animals arrive.”

Click on this link to access The Early Microbial Colonizers of a Short-Lived Volcanic Island in the Kingdom of Tonga published in mBio