The Hawaiian monk seal is extremely endangered, as is the only other remaining monk seal species—the Mediterranean monk seal. Sadly, the third monk seal species, the Caribbean monk seal, is already extinct. Threats to the Hawaiian monk seal include entanglement with fishing gear, lack of food, loss of breeding areas due to erosion, and disease. In the Mediterranean, coastal development and human interactions can displace the seals from their habitat. People have also hunted them for their oil, and to reduce competition with our fishing, as monk seals eat commercially important fish and other animals. Monk seals are incredible divers, reaching depths of more than 200 feet and staying under for up to ten minutes.
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Endangered Ocean Animals
The Endangered Species Act (ESA) was signed into law on December 28, 1973 by President Nixon. Over 2,000 species are currently on the ESA, and they are separated into "Threatened" and "Endangered" species. Endangered species are in danger of going extinct, while Threatened species are approaching Endangered status. The U.S. Fish and Wildlife Service manages those animals and plants listed that are found on land and in freshwater, and 137 marine species are managed by NOAA's National Marine Fisheries Service (NMFS). Species that spend only part of their life cycle in the ocean, like salmon and sea turtles, are managed by both! Although marine species only make up around four percent of the the total species on the endangered species list, that doesn't mean that most are doing fine. The ocean can be a difficult place to study and data about the animals there may be lacking.
Many marine species have ranges that extend beyond national borders, and trade in endangered species is a global phenomenon. In these cases, protecting threatened and endangered species is helped by international agreements, such as the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and the International Whaling Commission. For example, about one-fourth of the ESA listed species are not found in in the U.S. and its waters, but are protected in conjunction with CITES.
Monk Seals
Credit: James Watt
White Abalone
Credit: Cabrillo Marine AquariumThe white abalone was the first invertebrate to be listed under the Endangered Species Act in 2001, but it should have been sooner. Its California population collapsed almost two decades before it was listed, not long after a commercial fishery for the shelled mollusk opened in the 1970s. The species still hasn't recovered, largely because males and females of the sedentary abalones need to be in close proximity in order to reproduce—a difficult task when there aren't many abalones out there in the first place. Scientists are making attempts to help the population through the use of aquaculture.
Blue Whales
Credit: Jeremy GoldbogenThe largest of the whales, scientists estimate that there are between 5,000 and 12,000 blue whales throughout the ocean today. Whaling greatly depleted their population in the early 1900s. Although commercial whaling doesn't occur today, blue whales are still killed by getting caught in fishing gear, or from ship strikes. Here, a researcher places a tag on the large whale to track its movement.
Right Whales
Credit: Moira Brown/New England AquariumThe rarest of all the large whales, there are three distinct species of right whales—North Atlantic, North Pacific and Southern, all of which are endangered. It's estimated that only around 450 North Atlantic right whales remain after being hunted for their oil and baleen for generations. As with blue whales, the two primary threats to right whales today are ship strikes and entanglement with fishing gear. New shipping regulations in the waters off New England, including speed limits and recommended routes, are thought to be helping this species begin to recover.
Short-tailed Albatross
Credit: U.S. Fish and Wildlife ServiceIn the 1940s, the short-tailed albatross population plummeted from tens of millions to such a small number that they were believed to be extinct. Their decline was due to hunting for their feathers and damage to their breeding islands from volcanic activity. Keeping track of these migratory birds can be difficult. They nest and breed on islands off the coast of Japan, and then migrate to the West coast of the United States. Today they aren't hunted, but along with other albatross species, they are often caught mistakenly by longline fishing gear and can mistake plastic for food. In 2008, it was estimated that only 2,000 of the birds remained.
Staghorn & Elkhorn Coral
Credit: Albert KokStaghorn (seen here) and elkhorn corals are listed as Threatened under the ESA, as their numbers have fallen catastrophically due to disease. Listed in 2006, they were the only coral species under protection until 2014, when 20 other coral species were listed as threatened for a total of 22 species. Both staghorn and elkhorn coral are found in Caribbean waters and reproduce when bits of their branches break off and reattach to a hard surface. They also can reproduce through spawning, but only do so on a few days each year.
Johnson's Seagrass
Credit:Lori Morris, St. Johns River Water Management District
Johnson's seagrass is the lone ocean plant listed under the Endangered Species Act. Its flowing green stalks play an important role in coastal ecosystems where they act as nursery grounds for small larval fish, and are eaten by the also-endangered West Indian manatee and green sea turtle. Already the rarest seagrass in the U.S. due to its limited distribution, it is threatened by disturbance from boats, dredging, storm waves, and poor water quality.
Sea Turtles
Credit: Claudia Lombard, USFWSThe leatherback turtle (seen here) is the largest of the seven sea turtles, growing as long as six and a half feet (2 m) and weighing some 2,000 pounds (900 kg). All six of the species of sea turtles that are found in U.S. waters are listed as endangered under the ESA. Sea turtles face a variety of threats in both the ocean (like entanglement in fishing gear) and on land (such as artificial lights confusing newborn hatchlings).
The Vaquita
Credit:The vaquita (Spanish for “little cow”) is the world's smallest porpoise and usually grows only 5 ft (1.5 m) in length. Like Johnson’s seagrass, vaquitas have a very limited distribution, as they are just found off the coast of Mexico in the northern part of the Gulf of California. They are the most endangered of the marine mammals, with a population size of less than 600 animals. But estimating their numbers is a difficult task considering their elusive nature—vaquitas move toward the surface of the water very slowly, where they take a quick breathe and barely disturb the surface.