May 11, 2012 – “As the remotely operated vehicle (ROV) descended into the blue depths above the Alarcón Rise, the control room was abuzz with anticipation," wrote MBARI geologist Julie Martin in her April 22nd cruise log. "Today we [are] planning to dive on one of the strangest environments in the deep sea: a hydrothermal vent field.”

MBARI researchers have developed a new instrument that allows them to study the breathing of deep-sea animals without removing the animals from their environment.

Marine researchers want to know the effects of an increasingly acidic ocean, and have turned to two tide pool dwellers for some insight. It appears that mussels and purple sea urchins could tell scientists how marine life might adapt to changes in ocean acidity (pH).

Acorn worms have historically been thought of as shallow-water animals that live in burrows in muddy-bottom areas. Only four species were known to live in deep water. However, a recent paper by MBARI collaborator Karen Osborn and her coauthors shows that acorn worms live in the deep ocean environments around the world.

After six years of design and testing, MBARI scientists have a sophisticated new tool for studying the effects of ocean acidification on deep-sea animals. This complex system, the Free-Ocean Carbon Enrichment (FOCE) experiment, is the only experiment in the world that allows researchers to study ocean-acidification impacts on deep-sea animals in their native habitat, using free-flowing seawater.

Marine biologists are trying to figure out why males of some deep-sea squid mate with other males as often as they mate with females.

In late May of 2011, MBARI and the National Oceanic Atmospheric Administration’s (NOAA) National Data Buoy Center (NDBC) installed a new ocean-monitoring buoy about 30 miles offshore of Monterey Bay. This collaborative effort, brokered by the Central and Northern California Ocean Observing System (CeNCOOS), could pave the way for similar buoys maintained by NDBC around the country, providing a wealth of new scientific information.

The first comprehensive study of the biological effects of Antarctic icebergs shows that they fertilize the Southern Ocean, enhancing the growth of algae that take up carbon dioxide from the atmosphere and then, through marine food chains, transfer carbon into the deep sea.

Each year, an estimated 10,000 shipping containers fall off container ships at sea. Although many of these containers float at the surface for months, most eventually sink to the seafloor. No one knows what happens to these containers once they reach the deep seafloor.

Nature rarely hands over her secrets without a fight. Solving our planet's mysteries means doggedly following clues that may only reveal a small part of the story.

The Sargasso Sea is an ocean within an ocean, bounded not by land masses but by a vortex of swirling ocean currents—a place where mats of seaweed drift on the high seas and shelter a unique community of open ocean animals.

Dead whales that sink down to the seafloor provide a feast for deep-sea animals that can last for years. Previous research suggested that such "whale falls" were homes for unique animals that lived nowhere else.

Off the coast of Central California, in the inky darkness of the deep sea, a bright orange metal pyramid about the size of two compact cars sits quietly on the seafloor. Nestled within the metal pyramid is the heart of the Monterey Accelerated Research System (MARS)—the first deep-sea cabled observatory offshore of the continental United States.

Over the past decade, the undersea robots known as autonomous underwater vehicles (AUVs) have become increasingly important in oceanographic research.

In mid-September a small fleet of ships and robotic submersibles performed a novel experiment about 160 kilometers (100 miles) off the Central California coast. The vessels spent most of their time circling around a floating robotic DNA lab, which drifted southward in the California Current.

Squids are some of the most fascinating and diverse deep-sea animals. In this collection of short video clips, MBARI biologists highlight some of their favorite video clips of deep-sea squids.

Deep-sea animals have evolved a variety of ways of moving through the water. Some are graceful. Some are improbable. But all are fascinating. This new video prepared by MBARI's Video Lab staff shows just a few of these approaches to underwater locomotion.

Suppose you're walking along the beach and you see a jellyfish washed up on the sand. Then you see another and then another. It's a jellyfish invasion! What do you do? Who do you call? If MBARI researcher Steve Haddock has his way, you'll take some photos and maybe a few notes, and send them in to his new Jellywatch website (www.jellywatch.org), to share your discovery with the world.

With dimensions comparable to the Grand Canyon, it's no surprise that Monterey Canyon harbors a variety of different seafloor habitats. But even on the flat, muddy floor of the canyon, animal communities vary considerably, according to a new paper by marine biologists Craig McClain and James Barry.

When most people think about the deep sea, they picture broad expanses of muddy seafloor. However, the majority of deep-sea animals, and perhaps the majority of all animals on Earth, live in the "deep pelagic zone"--the dark waters between the ocean surface and the seafloor.