Southern Resident Killer Whale mother and her calf swimming.

Mom and baby sea turtle sleeping on the beach on the Big Island in Hawaii. Credit: Karyn Wagner

Mom and baby manatee swim in canal in St. Petersburg, Florida.

The many facial expressions of Northern fur seal pups. Credit: Eric Boerner, Alaska Fisheries Science Center, NOAA Fisheries Service

Mom and baby elephant seal just rolling around on the beach in Ano Nuevo Island, California.

Children discover ocean life at the Smithsonian National Zoo's invertebrates exhibit in Washington, DC.

NOAA’s LCDR Joe Pica diving with a humpback whale off Dominica Republic. His encounter with this humpback whale occurred during a routine dive off NOAA ship Gordon Gunter to recover an acoustic underwater buoy.

A northward view of the Big Sur coastline and Monterey Bay National Marine Santuary approximately 120 miles south of San Francisco, Calif. Bixby Creek Bridge, a popular landmark of this region, is visible in the distance.

Octopuses are boneless creatures. They are invertebrates with extremely flexible bodies that can squeeze through incredibly small spaces. An octopus has three hearts, nine brains, and blue blood. Two hearts pump blood to the gills, while a third circulates it to the rest of the body. The nervous system includes a central brain and a large ganglion at the base of each arm which controls movement. Octopus blood contains the copper-rich protein hemocyanin, which is more efficient than hemoglobin for oxygen transport at very low temperatures and low oxygen concentrations. Octopus, along with squid, cuttlefish, and nautalis, are cephalopods. Most of the hundreds of species of cephalopods have three hearts.

Polar bears have evolved to living in the extreme conditions of the Arctic. Polar bears and seals are dependent on sea ice for foraging, resting, and reproduction.

Starfish along the shore in Olympic Coast National Marine Sanctuary in Washington State. 2012 marks the 40th anniversary of the National Marine Sanctuaries Act, which established NOAA's National Marine Sanctuary system. Head to sanctuaries.noaa.gov for a link to a special website highlighting the top 40 accomplishments of the sanctuary system.

The wreck of the schooner E.B. Allen, located within Thunder Bay National Marine Sanctuary in Michigan. 2012 marks the 40th anniversary of the National Marine Sanctuaries Act, which established NOAA's National Marine Sanctuary system. Head to sanctuaries.noaa.gov for a link to a special website highlighting the top 40 accomplishments of the sanctuary system.

A manta ray in Flower Garden Banks National Marine Sanctuary off the coast of Florida. 2012 marks the 40th anniversary of the National Marine Sanctuaries Act, which established NOAA's National Marine Sanctuary system. Head to sanctuaries.noaa.gov for a link to a special website highlighting the top 40 accomplishments of the sanctuary system.

Aplysina fulva, a type of sponge characterized by long rope-like branches. This specimen lives within Gray's Reef National Marine Sanctuary off the coast of Georgia.

Sponges in Gray's Reef National Marine Sanctuary off the coast of Georgia. Within this sanctuary, there are rocky ledges with sponge and coral live bottom communities, as well as sandy bottom areas that are more typical of the seafloor off the southeastern U.S. coast.

Two starfish 'hanging out' on a sponge in Gray's Reef National Marine Sanctuary, located off the coast of Georgia.

Madrepora oculata is one of the deepest reef building stony corals in the world, known to occur as deep as 2020 meters. Colonies are distinguished by the zig-zag appearance of their branches. This colony is home to several squat lobsters at 750 meters depth in Roatan, Honduras. The green laser points in the lower center are 10 cm apart.

Not all sea fans are flexible enough to bend in the currents. This precious coral Corallium species has a rigid calcitic skeleton like stony corals. The sea fans are referred to as precious corals because they are harvested for the jewelry trade in some parts of the world. This particular colony is from 750 meters depth in Roatan, Honduras. The green laser points in the lower center are 10 cm apart.

A diver enjoys the sights in Gray's Reef National Marine Sanctuary. Gray's Reef is one of the largest near-shore live-bottom reefs of the southeastern United States. It's just one of the 14 national marine protected areas that make up the National Marine Sanctuary System.

Several deep-water sea fans (Plumarella pellucida) were photographed with a basket star at 150 meters (492 feet) using a remotely operated vehicle in Georgetown Hole, Ga. In April 2010, a team of researchers aboard NOAA ship PISCES explored deep coral habitat at a depth of 100-300 meters (361 to 984 feet) off Georgia, east of Gray's Reef National Marine Sanctuary in South Atlantic Bight. The team used a remotely operated vehicle, fisheries acoustics, and a grab sampler to collect corals and sediment. The rugged bottom topography and the coral mounds are attractive features for deep-sea reef fish like wreckfish and blackbelly rosefish. Large barrelfish and red bream also shelter in the rugged bottom.

Two species of brightly colored crinoids living upon a deep-sea black coral (Antipathes specie) near 300 meters (984 feet) depth in Roatan, Honduras. Pale yellow featherstars are likely Crinometra brevipinna. The banded white and orange featherstar may be Neocomatella pulchella, per Dr. Charles Messing, Professor of Oceanography, Nova Southeastern University Oceanographic Center. The green laser points visible in the lower right are 10 cm (3.98 inches) apart. In 2010 and 2011, a NOAA-led team of researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear.

Amberjacks swimming behind an outcropping of sponge coral in Gray's Reef National Marine Sanctuary.

An arrow crab perched on a sea urchin, Gray's Reef National Marine Sanctuary. Gray's Reef was designated as a sanctuary on January 16, 1981, and is the only protected natural reef area on the continental shelf off the Georgia coast.

Northern elephant seals, like all marine mammals, are protected under the Marine Mammal Protection Act.

Hawaiian spiny lobster at Necker Island in the Papahanaumokuakea Marine National Monument.

A red-footed booby at the Three Sisters at Pearl and Hermes Atoll in the Papahanaumokuakea Marine National Monument. Image credit: Claire Fackler, NOAA National Marine Sanctuaries

The deep-water sea fan Plumarella pellucida at 150 meter (492 feet) depth in Georgetown Hole, off the coast of Georgia. The genus Plumarella has pharmaceutical properties that may yield new drug discoveries one day. In April 2010, a team of researchers aboard NOAA ship PISCES explored deep coral habitat at a depth of 100-300 meters (361 to 984 feet) off Georgia, east of Gray's Reef National Marine Sanctuary in South Atlantic Bight. The team used a remotely operated vehicle, fisheries acoustics, and a grab sampler to collect corals and sediment. The rugged bottom topography and the coral mounds are attractive features for deep-sea reef fish like wreckfish and blackbelly rosefish. Large barrelfish and red bream also shelter in the rugged bottom.

Large colony of the deep-water coral Madracis myriaster at 150 meters (492 feet) in Roatan, Honduras. The green laser points visible in the lower right are 10 cm (3.98 inches) apart. In 2010 and 2011, a NOAA-led team of researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear.

The brightly colored brisingid seastar Novodinia antillensis is fairly common near 500 meters depth in Roatan, Honduras. In 2010 and 2011, a NOAA-led team of researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear.

Deepwater grouper in Madracis myriaster coral at 150 meters (492 feet) depth in Roatan. In 2010 and 2011, a NOAA-led team of researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear.

Southern sea otter, Enhydra lutris nereis, at South Harbor, Moss Landing, California. World Ocean Day Photo Contest Submission by Dr. Steve Lonhart.

A crab builds a home on a beach in the U.S. Virgin Islands. World Ocean Day Photo Contest Submission by Malinda Vagasky.

A red sea fan (Swiftia pacifica) with shrimp on the branches and crabs at the base. This is one of several images of rarely seen deep-sea animals captured on camera in Olympic Coast National Marine Sanctuary. During an Aug. 2011 expedition, researchers used a NOAA remotely operated vehicle in waters 328 to 656 feet deep (100 to 200 meters) off the Olympic Peninsula in Washington State. Research partners included NOAA's Olympic Coast National Marine Sanctuary, Southwest Fisheries Science Center, and Center for Coastal Environmental Health & Biomolecular Research; plus academic partners from Washington State University and crew of Oregon State University's R/V Pacific Storm. The research to study deep-sea corals was funded by NOAA's Coral Reef Conservation Program.

A school of canary rockfish (Sebastes pinniger). This is one of several images of rarely seen deep-sea animals captured on camera in Olympic Coast National Marine Sanctuary. During an Aug. 2011 expedition, researchers used a NOAA remotely operated vehicle in waters 328 to 656 feet deep (100 to 200 meters) off the Olympic Peninsula in Washington State. Research partners included NOAA's Olympic Coast National Marine Sanctuary, Southwest Fisheries Science Center, and Center for Coastal Environmental Health & Biomolecular Research; plus academic partners from Washington State University and crew of Oregon State University's R/V Pacific Storm. The research to study deep-sea corals was funded by NOAA's Coral Reef Conservation Program.

A white-lobed sponge. This is one of several images of rarely seen deep-sea animals captured on camera in Olympic Coast National Marine Sanctuary. During an Aug. 2011 expedition, researchers used a NOAA remotely operated vehicle in waters 328 to 656 feet deep (100 to 200 meters) off the Olympic Peninsula in Washington State. Research partners included NOAA's Olympic Coast National Marine Sanctuary, Southwest Fisheries Science Center, and Center for Coastal Environmental Health & Biomolecular Research; plus academic partners from Washington State University and crew of Oregon State University's R/V Pacific Storm. The research to study deep-sea corals was funded by NOAA's Coral Reef Conservation Program.

A spiny dogfish (Squalis acanthias) patrolling the seafloor. This is one of several images of rarely seen deep-sea animals captured on camera in Olympic Coast National Marine Sanctuary. During an Aug. 2011 expedition, researchers used a NOAA remotely operated vehicle in waters 328 to 656 feet deep (100 to 200 meters) off the Olympic Peninsula in Washington State. Research partners included NOAA's Olympic Coast National Marine Sanctuary, Southwest Fisheries Science Center, and Center for Coastal Environmental Health & Biomolecular Research; plus academic partners from Washington State University and crew of Oregon State University's R/V Pacific Storm. The research to study deep-sea corals was funded by NOAA's Coral Reef Conservation Program.

A humpback whale breaching in the Gulf of the Farallones National Marine Sanctuary, off the coast of California. Image credit: Robert Schwemmer, NOAA National Marine Sanctuaries

An osprey enjoying a nice breakfast in the Potomac River. World Ocean Day Photo Contest Submission by Kevin Watkins.

Giant Clams in Palau, Federated States of Micronesia World Ocean Day Photo Contest Submission by Doug Helton.

Did you know that, even though they live in the ocean all of the time, dolphins are mammals, not fish?

Sharks have gotten a bad reputation as "man eaters," but the reality is that less than 100 people are attacked by sharks each year and only a handful of species of sharks are responsible for such attacks. Most of the species out there have never been noted to attack a human.

Three willetts along the beach in Monterey, California. World Ocean Day Photo Contest Submission by Paul Jimerson.

Mirror reflection in Whittier, Alaska. World Ocean Day Photo Contest Submission by Henry Hauch.

An image of a crab backlit by the setting sun in West Bengal, India. World Ocean Day Photo Contest Submission by Arnab De.

A single colony of the black coral Bathypathes sp. forms habitat for two squat lobsters and a fish at 400 meters (1,312 feet) depth in Roatan, Honduras. In 2010 and 2011, a NOAA-led team of researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear. Image credit: NOAA DeepCAST I Expedition.

Four crinoids (feather stars) with a squat lobster on top of a sea fan colony with Lophelia pertusa growing at the base. The image is from 400 meters (1,312 feet) depth in Roatan, Honduras. In 2010 and 2011, a NOAA-led team of researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear. Image credit: NOAA DeepCAST II Expedition.

An aggregation of the reef building scleractinian coral Lophelia pertusa at 580 meters (1,903 feet) depth in Roatan, Honduras. In 2010 and 2011, a NOAA-led team of researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear. Image credit: NOAA DeepCAST I Expedition.

The brisingid sea-star Novodinia antillensis perched on a rock next to a primnoid sea fan colony at 610 meters (2,001 feet) depth in Roatan, Honduras. In 2010 and 2011, a NOAA-led team of researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear. Image credit: NOAA DeepCAST II Expedition.

This yellow sea fan is an octocoral colony in the family Paramuriceidae at 400 meters (1,312 feet) depth in Roatan, Honduras. The white forms in the branches are ophiuroid brittle stars (or "snake stars") in the genus Asteroschema. In 2010 and 2011, NOAA researchers explored the deep Meso-American Reef off Roatan, Honduras, as part of a multi-year expedition called 'Deep Coral and Associated Species Taxonomy and Ecology', or DeepCAST. The goal of DeepCAST is to estimate deep-sea coral abundance and diversity; and to discern the nature of the relationship between host corals and their associated species. The primary reasons we study deep-sea corals are because they provide habitat to other species of fish, sea stars, shrimp and crabs; and they grow very slowly, so they are vulnerable to bottom contact fishing gear. Image credit: NOAA DeepCAST I Expedition.

With distinctive reddish and white stripes, gracefully flowing fins, and menacing spines, few fish embody the beauty, mystery, and danger of the ocean quite like the lionfish. Although native to the Indo-Pacific region, lionfish were introduced to the Atlantic and are now found along the U.S. coast from North Carolina to Florida and in the Bahamas and Caribbean. The lionfish's lack of predators, voracious appetite, rapid reproduction, and fast growth spell trouble for the balance of invaded ecosystems and fisheries, as lionfish can out-compete native species for food and space.

Seventy-five percent of the world's coral reefs are currently threatened by local and global pressures, according to a 2011 analysis. The most immediate and direct threats arise from local sources, which currently threaten more than 60% of coral reefs. Local threats include impacts from fishing, coastal development, and pollution. Left unchecked, the percent of threatened reefs will increase to more than 90 percent by 2030 and to nearly all reefs by 2050.

DNA testing confirmed that the eggs pictured here were those of a loggerhead turtle, a marine reptile species listed as threatened under the Endangered Species Act. NOAA's Center for Coastal Environmental Health and Biomolecular Research in Charleston, S.C., runs the only laboratory in the country dedicated to the forensic analysis of marine species.

A manatee, also known as a 'seacow.' These air-breathing herbivores are listed as a federally endangered species. Manatees are slow-moving and therefore unable to swim quickly away from boats; this often results in collisions that may cause injury or death to the creatures. In areas that are known manatee habitats, "no-wake" signs are posted requiring boaters to slow down and produce only minimal wake.

Each year, the Hawaiian Islands Humpback Whale National Marine Sanctuary hosts the 'Sanctuary Ocean Count.' This a fun volunteer activity for residents and visitors on the islands of Oahu, Hawaii, and Kauai—and it helps to provide important population and distribution information on humpback whales around the Hawaiian Islands.

The balloonfish, also known as a porcupine or spiny puffer fish, swells up like a balloon when attacked.

A blue rockfish in Monterey Bay National Marine Sanctuary, Calif.

Pacific white-sided dolphins in California. Image credit: Robert Schwemmer, NOAA National Marine Sanctuaries

A loggerhead turtle captured on camera during an 'Aquarius 2010' dive. During the 10-day mission, students from around the country participated in live broadcasts with Aquanauts based on NOAA's Aquarius, the world's only undersea research station.

Close-up image of brain coral in the Dry Tortugas, Florida.

This school of permits contained 60-80 individuals, each over a foot long. The school was observed in the Dry Tortugas, Florida.

A lobster pokes out of its hiding spot under a coral head in the Dry Tortugas, Florida.

A Caribbean spiny lobster on the sea floor. This photo was shot during a 2010 NOAA expedition in the U.S. Virgin Islands to map underwater habitats and the marine life they support.

A sea anemone nestled in plate coral and various types of algae. This photo was shot during a 2010 NOAA expedition in the U.S. Virgin Islands to map underwater habitats and the marine life they support.

A sea lion is captured in mid-backflip off the California coast. Image credit: Robert Schwemmer, NOAA National Marine Sanctuaries

Coralline algae at Rose Atoll, located off the coast of American Samoa. An atoll is an island of coral that encircles a lagoon partially or completely.

A group of elephant seals sleep in the sun around a sand dune on Active Point, San Miguel Island, of the Channel Islands National Marine Sanctuary, off the coast of California. Image credit: Robert Schwemmer, NOAA National Marine Sanctuaries

Divers free a seal from fishing nets. The impacts of marine debris such as floating nets are wide ranging. From being an eyesore on a beach to injuring marine life or stopping a 400-ton vessel at sea, marine debris is a problem that we cannot ignore.

Horse-eye jacks (Caranx latus) swim by an NOS diver during a safety stop.

Kelp and sardines, Anacapa Island, Channel Islands National Marine Sanctuary. Image credit: Robert Schwemmer, NOAA National Marine Sanctuaries

A sharknose goby (Elacatinus evelynae) propped up on brain coral in the U.S. Virgin Islands.

Marine protected areas, such as Elkhorn Slough in California, are an important tool for managing the nation's natural and cultural marine resources, and are a key component of an ecosystem approach to management.

Eyes of a queen conch (Strombus gigas) peaking out from under its shell in La Parguera, Puerto Rico.

Staghorn coral, which is currently listed as threatened under the Endangered Species Act, observed in Carlos Rosaria Reef near Culebra, Puerto Rico.

A Manta Ray passes over a reef, inviting a host of small fish to clean parasites and other debris off of the giant animal. Manta Rays are the largest rays in the ocean.

A biologist from the Florida Keys National Marine Sanctuary photographs the damage done to a coral reef from a boat that grounded on the reef. An elkhorn coral branch broken in the incident appears in the foreground.

A sea lion poses for the camera in the waters off of California. Image credit: Claire Fackler, NOAA National Marine Sanctuaries

A scientist from the Center for Coastal Environmental Health and Biomolecular Research (CCEHBR) conducts a bottlenose dolphin necropsy demonstration for Coastal Carolina University (Conway, South Carolina) students. CCEHBR has provided necropsy demonstrations to the Coastal Carolina University Marine Mammal class since 1996 to provide students information on anatomy and the causes of natural and human-induced mortality.

A sea turtle swimming off of the Hawaiian islands.

Sponges and corals in Flower Garden Banks National Marine Sanctuary, Gulf of Mexico.