In the ocean's shadowy depths lies one of the Earth's last frontiers: the ocean twilight zone. It's a vast swath of water extending throughout the world's oceans from 650 to 3,280 feet (200 to 1,000 meters) below the surface, and it abounds with life: small but fierce-looking fish, giant glowing jellies, and microscopic animals that feed marine life higher up the ocean's food web.
This cold, dark, remote region of the ocean has remained largely unexplored, but a team of scientists and engineers from Woods Hole Oceanographic Institution have pioneered an ambitious new vehicle to blaze a trail into this ocean wilderness. Known as the Deep-See, it is a modern-day, subsea Conestoga wagon filled with a remarkable array of instruments designed to illuminate the ocean’s mysterious interior and reveal how many and what kinds of animals live there.
“To date, scientists have used several methods to explore the midwater depths, but each had its pros and cons,” said WHOI marine biologist Larry Madin. Acoustic sonars could detect masses of animals that reflected sound well, but they usually couldn’t distinguish individual species. Nets could bring back some intact animals, but they often squished the more gelatinous ones and missed those that were very small or could get out of the way. And cameras weren’t so effective at capturing images of animals that were sparsely distributed, moving, and often small or transparent.
Read more at Woods Hole Oceanographic Institution (WHOI)
Photo: WHOI mechanical engineer Kaitlyn Tradd (left) prepares the new towed vehicle Deep-See for its first mission, with help from engineering assistant Troy Petitt (center) and guest student Will Scott. The vehicle left on its first expedition to the ocean twilight zone in August 2018 aboard the NOAA research vessel Henry B. Bigelow. (Photo by Veronique LaCapra, WHOI)