In the deep waters of the ocean, there are no places to hide. To avoid predators, many deep-sea animals have dark-colored, reflective, or transparent bodies. Others have evolved elaborate methods of deception.

Sept 15, 2014 – Ocean researchers are on the verge of gaining new insights about the changing Southern Ocean with help from sensors developed by a research team at the Monterey Bay Aquarium Research Institute (MBARI).

Cephalopods—squids, octopuses, and their relatives—are some of the most beautiful and intriguing animals in the ocean. During the week of June 23-27, 2014, MBARI, the Monterey Bay Aquarium, and Science Friday teamed up to present a wonderful array of videos and still images of these creatures.

In the 100 years since marine biologists hauled the first vampire squid up from the depths of the sea, perhaps a dozen scientific papers have been published on this mysterious animal, but no one has been able to figure out exactly what it eats. A new paper by MBARI Postdoctoral Fellow Henk-Jan Hoving and Senior Scientist Bruce Robison shows for the first time that the vampire squid uses two thread-like filaments to capture bits of organic debris that sink down from the ocean surface into the deep sea.

In a recent paper, MBARI researcher Lonny Lundsten and his coauthors describe the first observations of these rare fish in their natural, deep-sea habitat.

  Axial Seamount, 480 kilometers (300 miles) off the coast of northern Oregon, is one of the best-studied underwater volcanoes in the world. For 30 years, researchers have explored this volcano using submersibles and monitored its activity using pressure sensors, tilt meters, temperature probes, and seismometers (earthquake detectors). Now MBARI researchers have created the world’s …

May 11, 2012 – MBARI engineer Andy Hamilton looks out his office window in Moss Landing and points at the waves crashing on the beach below. “Pretty impressive, aren’t they? You’d think there’d be a way to make use of all that energy.” Since 2009, Hamilton has led a team of engineers trying to do just that.

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.

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.

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.