The Deep Sea Gold Rush

The discovery of deep-sea hydrothermal vents in 1977 northeast of the Galapagos Islands sparked the realization that we as a species really knew nothing about our planet’s largest habitat: the seabed. Hydrothermal vents are like deepsea hot springs, caused by magmaemitting cracks in the seafloor rapidly heating cold seawater and forcing it up through chimney structures formed by the precipitation of this now mineralrich seawater.

The deep sea is mankind’s penultimate frontier, where the creatures and their way of life are so alien to us that they are actually helping us understand things as far reaching as yet undiscovered life on other planets. The unique and wonderful biological communities found to thrive in hydrothermal vents are the first and only example of marine life being sustained in the complete absence of sunlight. Unlike most other ecosystems on earth, which rely on primary production by photosynthetic organisms, hydrothermal vent species rely on primary production from chemosynthetic bacteria. These bacteria, either free-living or in a symbiotic relationship with certain vent fauna, feed of the chemicals spewed from the seabed and become the base of unique food chains. Some animals such as tube worms are so dependent on these chemosynthesizing bacteria that they have completely done away with their digestive system and replaced it with a trothosome, which is effectively a bag for their symbiotic bacteria. Alternatively, the Hoff crab— named after David Hasselhoff for its hairy chest—feeds off the microbial mats that cover the seafloor around vents by cultivating them on their Hofflike chest hair.

The existence of sunlight-independent life on earth implies that similar life may occur elsewhere in the universe and even on certain moons in our own solar system! As if that suggestion isn’t spectacular enough, a recent study lead by researchers from the New York Center for Astrobiology suggests all life on earth may have originated at hydrothermal vents as they contain the conditions required to synthesize life’s organic building blocks from inorganic compounds.

The precipitation of minerals at hydrothermal vents is key to the scientific intrigue surrounding them, but may also be their downfall. As ever, that which has great scientific value also holds a more tangible— but ultimately finite—monetary value. Before I continue I should point out that, as a conservation ecologist, I am inevitably biased; however, I do believe it is possible to simultaneously explore, exploit, and safeguard any ecosystem if we can strike the right balance.

So who wants to exploit hydrothermal vents, and who in the world owns them? The answer to both of those questions is everyone. With the increasing production of personal computers, from smartphones to laptops, the rare metals constituents from these vents are becoming more valuable and, well, rare. Many desirable rare metals, such as gold and copper, are found in high quantity and quality within deposits at hydrothermal vents. So the arms race is on and the weapons of mass destruction have been built. “When will the madness begin?” I hear you cry. The answer is as early as April right here in Okinawa. Well, not right here, but one thousand kilometers northwest of here in the Okinawa Trough at a vent field known as the Izena Cauldron.

The Okinawa Trough is home to at least eight hydrothermal vent fields, each containing multiple vents and associated ecosystems, with new ones being discovered all the time. When compared to the many other hydrothermal vents found around Japan, those within the Okinawa Trough support such unique and diverse species that lead-author Ryota Nakajima recommends they should be considered a priority for protection. But do not despair; as we speak the Mitarai Unit within OIST is studying the hydrothermal vents in Okinawa and beyond. The work is focused on the level of connectivity between hydrothermal vent population, knowledge the international scientific community agrees is vital to the implementation of reserves designed to protect these ecosystems.

 So I claimed we all own the hydrothermal vents, and maybe you got a bit excited because I also mentioned gold. The truth is the vents in the Okinawa Trough are owned by Japan and the people of Japan as they sit within Japanese national waters. The majority of hydrothermal vents however are believed to rest in international waters beyond any country’s jurisdiction. This means all countries and peoples of this earth have a stake in the future of hydrothermal vents. This shared ownership could result in the mismanagement of this precious resource, but it may also be its saving grace. As part owners we can all play a part in ensuring hydrothermal vents are correctly managed by not ignoring them and by insisting on their importance as more than just another mine on the earth’s surface. So get online and learn more about the rapidly-expanding field of deep-sea conservation. Check out the recommended further reading and keep up-to-date with the latest deep-sea conservation projects; you can also find an interactive map of all deep-sea mining efforts, the scale of which may shock you. Far too easily does that which is out of sight and out of mind also run out of time.

Further reading:

“Deep Sea Conservation Coalition,”, last modified January 25, 2017,

“International network for scientific investigation of deep-sea ecosystems,” INDEEP, last modified December 2016,

“Deep Sea Mining Watch,” UCSB Benioff Ocean Initiative, last modified September 4, 2016,!/home?layers[]=vessel-tracks&layers[]=isa-areas&layers[]=labels&view=0.3516|-159.9609|1||965|741.


1Bradley T. Burcar, Laura M. Barge, Dustin Trail, E. Bruce Watson, Michael J. Russell , and Linda B. McGown, “RNA Oligomerization in Laboratory Analogues of Alkaline Hydrothermal Vent Systems,” Astrobiology 15, no. 7 (2015): 509.

2Ryota Nakajima, Takehisa Yamakita, Hiromi Watanabe, Katsunori Fujikura, Katsuhiko Tanaka, Hiroyuki Yamamoto, and Yoshihisa Shirayama, “Species richness and community structure of benthic macrofauna and megafauna in the deep-sea chemosynthetic ecosystems around the Japanese archipelago: an attempt to identify priority areas for conservation,” Diversity and Distributions 20 (2014): 1120.

Images from top to bottom:

  1. AD Rogers, PA Tyler, DP Connelly, JT Copley, R James, RD Larter, et al. “The Discovery of New DeepSea Hydrothermal Vent Communities in the Southern Ocean and Implications for Biogeography,” PLoS Biol 10, no. 1 (2012): e1001234.

  2. Tubeworms on blacksmoker, courtesy of CSSFROPOS/NEPTUNE Canada

  3. Satoshi Mitaraia, Hiromi Watanabeb, Yuichi Nakajimaa, Alexander F. Shchepetkinc, and James C. McWilliams, “Quantifying dispersal from hydrothermal vent fields in the western Pacific Ocean,” PNAS 113, no. 11 (2016): 2976

Otis Brunner is an intern in the Mitarai Unit. His goal is to immerse himself in the society and science of OIST as much as possible. The marine environment is his workplace as well as his playground, which is why Okinawa is where he wants to be.