"Ameken's Deep Sea Research Voyage Report," presented by Kentaro Amemiya of Tokyo Sea Life Park, also known as Ameken, is back after a long hiatus.

I am currently aboard the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) research vessel "Natsushima," off the coast of the Mariana Islands. Around the ship, a deep blue, truly azure sea stretches out, and nothing but clouds are visible to the horizon. I truly feel like I'm in the middle of the vast ocean. From here, we will pass off the coast of the Ogasawara Islands and begin a research voyage of approximately two weeks to Yokosuka.

The purpose of this research cruise, in which I am currently participating, is to study the organisms around hydrothermal vents scattered throughout the sea area from the Izu and Ogasawara Islands to the Mariana Islands.

We will use the unmanned submersible Hyper Dolphin (see the link below for details) to dive to the seabed where hydrothermal vents are located and observe the organisms and their habitats there.

Then, in order to study the creatures there in detail, some of them are collected, taken back, and kept and observed. The aquarium is then in charge of caring for these creatures.

Many people may not be familiar with the term "hydrothermal vent." Simply put, it's like a hot spring bubbling up from the seabed. However, even though it's called a hot spring, the temperature can reach 300°C, and various chemical substances are spewed out along with the hot water.

While some hydrothermal vents contain toxic substances like hydrogen sulfide, making them extremely harsh environments for humans, they are home to bacteria and other organisms that use the hydrothermal fluids and chemicals to produce nutrients. These organisms then gather together to utilize or feed on these bacteria, forming an ecosystem known as a "hydrothermal vent community." This community is home to an astonishing number of organisms for the deep sea.

What kind of organisms make up hydrothermal vent communities? Their appearance will be revealed during the dive that is about to begin.

Next time, we'll introduce the organisms found in hydrothermal vent communities. Stay tuned!

Photo: Hyper Dolphin, fully loaded with research equipment, awaits dive.
(Photography assistance provided by: Japan Agency for Marine-Earth Science and Technology [JAMSTEC])

Ameken's Deep Sea Exploration Voyage Report
Part 1
Part Two
Part 3
Number four
Extra episode

[Tokyo Sea Life Park]

(July 30, 2010)