Cephalopods, crustaceans and other shellfish play important roles in maintaining healthy ocean systems. Cephalopods like the southern blue-ringed octopus and the vampire squid look other-worldly, while Atlantic blue crab and American lobster are the focus of major fishing industries.
Learn fun facts about how you can help protect your favorite octopus, crabs and more by clicking a species below.
Barnacles, somewhat surprisingly, are crustaceans (like crabs, lobsters, krill, etc.). Unlike most crustaceans, however, adult barnacles are sessile – they can’t move. After a short phase spent as planktonic larvae, barnacles settle, attach to a hard substrate, and never move again. The Acorn Barnacle is one species in a large group of species with the … Read more
The rings of a southern blue-ringed octopus are particularly vivid when an individual is threatened or agitated. In addition to the bright blue rings, these octopuses are famous for having extremely potent venom that can be strong enough to kill a person. There is currently no known anti-venom to treat a person who has been bitten. The southern … Read more
Red king crabs are covered with a spiny exoskeleton that provides them some protection from potential predators, but at different stages of its lifecycle, the species is preyed upon by fishes, octopuses, and some marine mammals. Red king crabs are also known to be occasionally cannibalistic. Red king crabs are omnivorous and will eat just … Read more
The queen conch is a large marine snail that lives in the Caribbean Sea and adjacent waters and is one of the most valuable fishery resources for every country throughout its range. Reaching its maximum length of approximately one foot (30 cm) in three to five years, the queen conch spends its growth resources thickening … Read more
Like many squids, the Humboldt squid grows rapidly and likely lives for only a single year. During that time, it reaches its maximum size, reproduces multiple times, and dies. Humboldt squid reproduce via internal fertilization and lay large egg masses of at least one million eggs. In their short lifetime, females may lay as many as 20 million … Read more
Females are also brightly colored but are mostly red. Peacock mantis shrimp are powerful hunters, feeding on hard-shelled invertebrates of all kinds and even some fishes. They are well known for the extremely fast punching motion that they do with their front appendages to kill and break apart their prey. This punch is one of the fastest movements … Read more
The name dumbo octopus refers not just to one species but to an entire genus of deep-sea umbrella octopuses, noted for their fins that resemble Dumbo the elephant’s ears (of Disney fame). There are at least 15 species of dumbo octopuses, and like all umbrella octopuses, their arms are connected by a web of skin, … Read more
The colossal squid is a massive squid that lives in the deep sea surrounding Antarctica, and it is the holder of multiple records. Not only is it the largest invertebrate on Earth, it also has the largest eyes of any animal, larger even than those of the great whales. Human knowledge of the colossal squid … Read more
The Atlantic blue crab (also known as the Chesapeake Blue Crab) is a common species along the east coast of the United States and in the Gulf of Mexico and lives as far south as Argentina. It is named for its blue color (in life) and is a favorite seafood species throughout its range. This … Read more
The common limpet is an herbivorous marine snail that lives along the rocky shores of Western Europe. As they live in the intertidal zone (the area along the shore between the high tide and low tide sea levels), these limpets are extremely well adapted to an amphibious life. The thick, conical shell and strong, muscular … Read more
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We have already protected nearly 4 million square miles of ocean and innumerable sea life - but there is still more to be done.