Originally designed to live on land, marine mammals are a diverse, charismatic group of animals that include more than 120 species. The animals share key characteristics of land mammals. They have hair, breathe air, give birth to live young, which feed off mother's milk when young. They have warm bodies and usually thick blubber to keep their body temperatures high. The bottlenose dolphin is probably the most widely recognized marine mammal, easily spotted just offshore from beaches around the world. Small groups of 20 or less can live in close proximity to shorelines, but groups living more offshore can reach several hundred. Bottlenose dolphin calves stay with their mothers for up to six years, learning how to hunt and become good dolphin citizens. Full-grown dolphins reach eight to 12 feet in length and can weigh up to 1,430 pounds. The bottlenose dolphin is protected in U.S. waters.
What makes them "marine" depends on the animal. They either live mostly in the sea or, like polar bears, depend on the ocean for food. The largest in the group are whales -- including humpback whales. These massive animals reach up to 50 feet in length and weigh up to 79,000 pounds. To maintain their weight, the animals feed on tons of krill and fish. They neared extinction due to whaling, but have recovered somewhat since a 1966 moratorium on whaling was introduced.
While polar bears live mostly on land or ice, they are excellent swimmers and have been known to swim up to 45 miles a day. The massive animals, weighing up to 1,500 pounds, hunt mostly seals. In recent years, biologists have observed that the bears are swimming now more than ever as melting stretches the distances between Arctic ice flows. Because they depend on sea ice to hunt seals, the polar bear is considered threatened as global warming melts and thins ice in this region.
This member of the weasel family is also the smallest marine mammal, with females weighing about 60 pounds and males weighing up to 90 pounds. They may be small, but they're also clever. They're the only marine mammals known to use tools. They use stones to break open clams and store food they gather in the folds of their armpits! Another feature that sets them apart is their lack of blubber. These marine mammals depend mostly on their fur to stay warm. That feature makes them particularly vulnerable to oil spills, which can compromise their fur's insulating effect.
Immediately recognizable by its long tusks and whiskers, the sea walrus is a hefty, flippered member of the Odobenidae family and is, in fact, the last living member of this group. Since both the males and females have big tusks and not much for teeth, the animals feed by sucking up shellfish from the ocean floor. So, just what are those tusks for? The longer they are (they grow to be up to four feet long in males), the higher an animal is ranked in the group. Males attack each other with their tusks to establish dominance. The ivory appendages are also handy for poking holes in the winter ice and for helping the animals pull themselves out of the water.
Manatees, also known as sea cows, are gentle herbivores that live in marshy areas in tropical and subtropical waters. The average adult manatee can weigh up 1,200 pounds and is around 10 feet long. Because of their slow metabolism, these animals can only survive in warm waters. Due to the unusually long, cold winter this year in part of the southeastern United States, populations of manatees throughout Florida were devastated. During the day, manatees usually like to stay close to the surface. At night, manatees will often sleep about three to 10 feet below sea level. This is why these gentle animals are so often accidentally injured, maimed or killed by passing boats.
Found up and down the North American coastlines, these marine mammals spend half of their lives swimming. Although they can reach up to six feet in length and weigh around 180 pounds, when on land and in plain sight harbor seals may not be easy to spot. Their spotted brown or tan fur allows harbor seals to blend in with sand and rocks. Unlike their very vocal relatives -- sea lions and elephant seals -- harbor seals are quiet creatures that make little noise. They like to hang out on beaches, sand bars and rocks during low tide to bask in the sun and sleep, but they never go far from the water. At the slightest sign of danger, they will quickly slip back under the waves. These expert swimmers have been known to plunge to depths of more than 1,600 feet and stay underwater up to 28 minutes.
UPDATE: The orcas slated to be an attraction at the Sochi Olympics will not be put on display, reports OneGreenPlanet.org. The killer whales will, however, remain in captivity, most likely to be used for entertainment in marine amusement parks, the site reported yesterday.
The Olympic Games in Sochi, which are starting in a few weeks, will likely feature a bizarre attraction: two killer whales.
The Vancouver Sun reported today that officials at Sochi's aquarium, Aquatoria, have confirmed that one killer whale has been captured and is acclamating at a “specially equipped base.”
Orca monitoring groups have had their eyes on this possibility since 2012, reports the Sun. Now that it has become reality, an online petition has been started, demanding that the whales not be on show during the Games. Almost 35,000 people had signed as of this writing.
This is what the petition says.
The Olympic Charter states:
“The IOC’s role with respect to the environment
is: to encourage and support a responsible
concern for environmental issues, to promote
sustainable development in sport and to require
that the Olympic Games are held accordingly.”
Chapter 1, Rule 2, Paragraph 13 of the 2011
2 young wild Orcas have recently been stolen from their natural environment and their family pod, and sent to Sochi Dolphinarium purely for the purpose of maximizing profits during the 2014 Winter Olympics.
Allowing these 2 Orcas to be captured from the sea as a DIRECT consequence of the 2014 SOCHI WINTER OLYMPICS breaks many rules of the Olympics Environment Mandates.
We call upon Thomas Bach & the IOC to ensure that these 2 Orcas are URGENTLY returned and released back into the Sea of Okhotsk to be reunited with their family.
It is the IOC's DUTY to uphold the Olympic Charter rules & the ensure that Olympic Host cities COMPLY with the United Nation's Agenda 21 document.
THE WORLD IS WATCHING.
Global Olympic Dolphins
Some killer whale experts say that putting an orca in captivity is akin to animal abuse, causing the animal great stress. Indeed, it's thought that the deadly 2010 attack on its trainer by Sea World's orca, Tilikum, was provoked by sensory deprivation, isolation, boredom and too-frequent breeding.
And that attack was not an isolated one. Other orcas have attacked their trainers, too, sparking a public controversy -- including a high-profile documentary called "Blackfish" -- over whether whales and dolphins should be kept in captivity at all.
As for the orca exhibit in Sochi, it's imaginable that the question isn't whether it will go on, but how many whales will be in it: one or two.