
A Hubrechtia ribbon worm, found after a long day of searching in mud flats in Fort Pierce, Florida.
Eduardo Zattara, Smithsonian Institution

Seagrass meadows, such as this one composed of turtle grass (Thalassia testudinum and manatee grass (Syringodium filiforme), are an important shallow water habitat.
Heather Dine, Florida Keys National Marine Sanctuary

A humpback whale breaching in Antarctic waters.
Ari Friedlaender

This still of a giant squid is from the first video filmed of the species in its natural habitat.
NHK/NEP/Discovery Channel

Fish swim around the wreck of the HMT Bedfordshire, an Arctic fishing trawler that was converted into an anti-submarine warship during World War II, and sunk off the coast of North Carolina.

Ari Friedlaender, a research scientist at the Duke University Marine Lab, tags a blue whale.
Jeremy Goldbogen

These zooplankton collected on a research cruise include a jellyfish, a lanternfish, a snipe eel, two large orange shrimp, a fuzzy pyrosome (which is bioluminescent), and several smaller animals.
Exploring the Inner Space of the Celebes Sea 2007 Exploration, NOAA-OE.

The whitish spots on this fish are individual parasitic trematode worms.
Hans Hillewaert

A whale shark swims with a diver off the coast of East Africa.
Caine Delacy

Red Pigfish and Blue Mao-Mao school at the edge of a cavern in New Zealand's Poor Knights Islands. Read photographer Brian Skerry's story behind this photo.
Brian Skerry, National Geographic
