15 Feb 2021

More research needed on deep sea mining - experts

8:53 am on 15 February 2021

Ocean scientists say the importance of providing Pacific governments with accurate data about the potential impacts of deep sea mining cannot be underestimated.

Underwater seascape sandy seabed with natural sunlight below water surface in the Mediterranean sea, France

Photo: 123RF

There's growing interest from mining companies in polymetallic nodules on the seabed of the Pacific Ocean.

A number of Pacific Island governments are backing exploration efforts by these companies.

University of Hawaii Department of Oceanography professor Jeffrey Drazen is among scientists working in this area in the Pacific.

While there is still much to be learnt he said the damage risks were high for such a slow-evolving ecosystem as the ocean floor.

"If you drive a vehicle across a lawn and it's a little bit wet, you get tyre tracks on the lawn, and it's unsightly, and we don't like them. But they typically are gone in a few weeks or a month. If you drive a vehicle across the deep sea floor, those tyre marks are there for decades. Decades upon decades. They don't go away."

University of California ocean science professor and Benioff Ocean Initiative director Douglas McCauley said it was important that the whole community was informed.

"Hard to see a brand new industry with such potentially revolutionary impacts or potentially significant impacts on ocean health happening in a space that is so little studied, as of yet."

Professor McCauley identified three main areas of potential impacts from potential mining: on fisheries, biodiversity and also climate change.

"So a lot of the material that's stored in the deep ocean where (they're) proposing to mine is ancient carbon. It's locked up in these sort of carbon vaults. That is where we want it, safely stored away from circulation in our global system.

"Cook Islands, Nauru, Kiribati, Tonga, are all very interested and bullish on mining. On the other hand you have countries like Fiji, PNG, Vanuatu that are saying we just don't have enough science right now to make informed decisions about going forward with ocean mining, therefore we're going to pause."