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Ocean Twilight Zone


Ocean Twilight Zone Art

Learn how to draw and paint the marvelous creatures of the ocean twilight zone and pick up some fun facts about their anatomy and behavior along the way!

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A Window into the Twilight Zone

Woods Hole Oceanographic Institution oceanographer Andone Lavery and her team of scientists and engineers have created the ultimate tool for exploring the largest, least known habitat on Earth—the Twilight Zone, a layer of the ocean beyond all but the dimmest sunlight. What they find might change our understanding of deep-ocean life.

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The ocean’s carbon pump works better than we thought!

Scientists have long known that the ocean plays an essential role in capturing carbon from the atmosphere, but a study from Woods Hole Oceanographic Institution (WHOI) shows that the efficiency of the ocean’s “biological carbon pump” has been drastically underestimated, with implications for future climate assessments. Marine chemist Ken Buesseler and his co-authors call on their fellow oceanographers to adopt a new metric for estimating the depth of the ocean’s sunlit layer, thus its ability to take up carbon.

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Hyperiid amphipod: a shimmer in the net

This hyperiid amphipod is a member of the crustacean family that typically act as parasites to gelatinous neighbors, such as salps. This particular suborder lives exclusively in the marine environment. Paul Caiger, who snapped the picture, saw this particular shrimp-like species during an ocean twilight zone research cruise on R/V Neil Armstrong (2020).

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360˚ Video: Deploying Mesobot

You’re on deck as the stealthy underwater robot Mesobot makes another trip into the ocean twilight zone to test equipment that will help scientists track bits of “environmental DNA” floating in the water.

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The Ocean Twilight Zone: Earth’s Final Frontier

The mysteries of the ocean twilight zone are waiting to be explored. What was once thought to be desert-like isn’t a desert at all. Where the deep sea creatures lurk there are incredible biomass and biodiversity. The ocean twilight zone is a huge habitat that is very difficult to explore. Woods Hole Oceanographic Institution is poised to change this because we have the engineers that can help us overcome these challenges. Making new discoveries in ocean exploration is more important now than ever.

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Report reveals ‘unseen’ human benefits from ocean twilight zone

A new report from researchers at Woods Hole Oceanographic Institution (WHOI) reveals for the first time the unseen—and somewhat surprising—benefits that people receive from the ocean’s twilight zone. Also known as the “mesopelagic,” this is the ocean layer just beyond the sunlit surface.

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Value Beyond View: The Ocean Twilight Zone

How does the ocean twilight zone benefit life on Earth? The ocean twilight zone helps regulates our climate. Storing two to six billion tons of carbon annually. That’s up to six times the amount of carbon emitted from autos worldwide. Preventing an increase in temperature between 6-11°F. The ocean twilight zone supports a healthy ocean ecosystem. Containing 10 times more fish than the rest of the ocean. Providing food for many other animals in the ocean. The ocean twilight zone could also play an important role in feeding a growing population. We are working to better understand this realm in order to inform sustainable management decisions.

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Open Ocean Diving Observations

Watch and learn how blue and black water diving is conducted in the open ocean and what these divers see during the day and during the twilight zone migration at night.

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Tagging Sharks to Study the Twilight Zone

Former WHOI Joint Program graduate student and current University of Washington postdoc Camrin Braun and his team on the charter fishing vessel Machaca managed to tag two porbeagles, a relative of the goblin shark, about 30 miles east of Chatham, Mass. One was a female nearly seven feet long and weighing 270 pounds. A male came alongside the boat while the team was tagging her and, when they were finished, they quickly hooked the curious male, which measured 6.5 feet and weighed 230 pounds.

Both fish are now equipped with fin-mounted SPOT satellite tags, which will report their location each time they surface and can last up to five years. For the Ocean Twilight Zone team, the big predators are an important indicator of where mesopelagic animals are collecting deep below the surface. In short, the predator will go where the prey is.

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Paul Caiger hunts for things that glow in the Ocean Twilight Zone

Paul Caiger is a fish biologist, marine photographer and postdoctoral investigator at Woods Hole Oceanographic Institution (WHOI). From the ghoulish grimace of the viperfish, to the bejeweled beauty of the strawberry squid, Caiger’s marine portraits have helped shine a light in this dark but critical ocean zone.

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A pop of red in the twilight zone

This bejeweled beauty is a strawberry squid (Histioteuthis reversa), sampled from the ocean twilight zone, a mysterious stratum of the ocean between the sunlit surface layer and extending down to about 1,000 meters (3,300 feet) deep.

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The Ocean Twilight Zone’s crucial carbon pump

Ken Buesseler

When CO₂ enters the ocean, where does this heat-trapping gas go? WHOI geochemist investigates how much carbon from the surface ocean is dispatched to the ocean twilight zone–the midlayer of the ocean–and on to the deep ocean.

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New Eyes in the Twilight Zone

Members of WHOI’s Ocean Twilight Zone team, particularly the lab led by marine biologist Annette Govindarajan, are pioneering the use of environmental DNA (eDNA) sampling and analysis to provide a more finely tuned picture of what lives deep beneath the surface of the ocean.

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Top of Mind with Julie Rose

BYU Radio

Associate Scientist Joel Llopiz describes the vast, virtually unexplored ecosystem lurking beneath the surface of the ocean known as the twilight zone. It is deep enough that it hasn’t really been affected by humans yet. But commercial fishing companies are eyeing it now, so scientists who study the Twilight Zone are urging the UN to establish some rules for it soon. (segment begins at 23:08)

Why we must protect the ocean’s ‘twilight zone’

Mother Nature Network

The twilight zone can be found 200 to 1,000 meters (about 650 to 3,300 feet) below the ocean surface, at the point where the sun’s rays can no longer reach, according to the Woods Hole Oceanographic Institute (WHOI) in Massachusetts. Because it’s so deep and there’s no sunlight, it’s cold and dark.

Minion robots in the Ocean Twilight Zone

Phytoplankton use sunlight and carbon dioxide to grow, forming the base of the ocean food web. Phytoplankton are eaten by zooplankton, which are eaten by other animals. Dead zooplankton and other particles become marine snow drifting in the ocean, but how much marine snow sinks below the sun-lit ocean surface? Scientists are developing a new device
that will follow marine snow into the ocean’s twilight zone.

The MINION is a small (2 Liters) inexpensive instrument. It is equipped with… cameras, seawater sensors, acoustic recorder, ballast weight. Once deployed, MINION will sink to the twilight zone and drift with currents.

Cameras on the side record the rate and quantity of particles falling through the ocean. Falling particles also accumulate on a clear glass panel. A camera on top will record the particle type and accumulation rate.

Similar images have revealed the twilight zone is a perpetual snowstorm, of organic debris. Particles such as this fecal pellet from a jellyfish-like salp are extremely carbon-rich. Pellets like this will sink quickly to deeper waters, or even become buried in the seafloor. Any marine snow that reaches the deep ocean means less carbon in the atmosphere.

The MINION is designed to listen for underwater sound sources. This will determine their location as they drift.

After a MINION has finished its mission, it will release weight and float to the surface. At the surface, it sends a homing signal so it can be recovered. The next generation of MINION will send compressed data-sets via satellite. Allowing them to be deployed by the dozens. Data from MINIONS will help scientists learn more about the ocean’s role in Earth’s climate system.

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