Leopard Seal Facts

Leopard Seal Facts If you get the opportunity to take an Antarctic cruise, you may be lucky enough to see a leopard seal in its natural habitat. The leopard seal  (Hydrurga leptonyx) is an earless seal with  leopard-spotted fur. Like its feline namesake, the seal is a powerful predator high on the food chain. The only animal that hunts leopard seals is the killer whale. Fast Facts: Leopard Seal Scientific Name: Hydrurga leptonyxCommon Names: Leopard seal, sea leopardBasic Animal Group: MammalSize: 10-12 feetWeight: 800-1000 poundsLifespan: 12-15 yearsDiet: CarnivoreHabitat: Sea around AntarcticaPopulation: 200,000Conservation Status: Least Concern Description You might think the obvious identifying feature of the leopard seal is its black-spotted coat. However, many seals have spots. What sets the leopard seal apart is its elongated head and sinuous body, somewhat resembling a furry eel. The leopard seal is earless, about 10 to 12 feet long (females slightly larger than males), weighs between 800 and 1000 pounds, and always seems to be smiling because the edges of its mouth curl upward. The leopard seal is large, but smaller than the elephant seal and walrus. The mouth of the leopard seal turns upward at the edges, resembling a smile. Peter Johnson/Corbis/VCG / Getty Images Habitat and Distribution Leopard seals live in the Antarctic and sub-Antarctic waters of the Ross Sea, Antarctic Peninsula, Weddell Sea, South Georgia, and Falkland Islands. Sometimes they are found along the southern coasts of Australia, New Zealand, and South Africa.  The leopard seals habitat overlaps that of other seals. Diet Leopard seals eat penguins.  © Tim Davis/Corbis/VCG / Getty Images The leopard seal will eat just about any other animals. Like other carnivorous mammals, the seal has sharp front teeth and fearsome-looking inch-long canines. However, the seals molars lock together to make a sieve that allows it to filter krill from the water. Seal pups primarily eat krill, but once they learn to hunt, they eat penguins, squid, shellfish, fish, and smaller seals. They are the only seals that regularly hunt warm-blooded prey.  Leopard seals often wait underwater and propel themselves out of the water to snatch their victim. Scientists can analyze a seals diet by examining its whiskers. Behavior Leopard seals are known to play cat and mouse with prey, typically with young seals or penguins. They will chase their prey until it either escapes or dies, but wont necessarily eat their kill. Scientists are uncertain of the reason for this behavior, but believe it may help hone hunting skills or might simply be for sport. Leopard seal males hang under the ice when they sing. Michael Nolan / Getty Images During the austral summer, male leopard seals sing (loudly) underwater for hours each day. A singing seal hangs upside down, with a bent neck and pulsating inflated chests, rocking from side to side. Each male has a distinct call, although the calls change depending on the seals age. Singing coincides with the breeding season. Captive females have been known to sing when reproductive hormone levels are elevated. Reproduction and Offspring While some kinds of seals live in groups, the leopard seal is solitary. Exceptions include mother and pup pairs and temporary mating pairs. Seals mate in summer and give birth after 11 months gestation to a single pup. At birth, the pup weighs around 66 pounds. The pup is weaned on the ice for about a month. Females become mature between ages three and seven. Males mature a bit later, typically between ages six and seven. Leopard seals live a long time for a seal, partly because they have few predators. While the average lifespan is 12 to 15 years, its  not uncommon for a wild leopard seal to live 26 years. Conservation Status According to the National Oceanic and Atmospheric Administration (NOAA), scientists once believed there may be over 200,000 leopard seals. Environmental changes have dramatically affected species the seals eat, so this number is likely inaccurate. The leopard seal is not endangered. The International Union for Conservation of Nature (IUCN) lists it as a species of least concern. Leopard Seals and Humans Leopard seals are highly dangerous predators. While attacks of humans are rare, cases of aggression, stalking, and fatalities have been documented. Leopard seals are known to attack the black pontoons of inflatable boats, posing an indirect risk to people. However, not all encounters with humans are predatory. When National Geographic photographer Paul Nicklen dove into Antarctic waters to observe a leopard seal, the female seal he photographed brought him injured and dead penguins. Whether the seal was trying to feed the photographer, teach him to hunt, or had other motives is unknown. Sources Rogers, T. L.; Cato, D. H.; Bryden, M. M. Behavioral significance of underwater vocalizations of captive leopard seals, Hydrurga leptonyx.  Marine Mammal Science.  12  (3): 414–42, 1996.Rogers, T.L. Source levels of the underwater calls of a male leopard seal.  The Journal of the Acoustical Society of America.  136  (4): 1495–1498, 2014.Wilson, Don E. and DeeAnn M. Reeder, eds. Species: Hydrurga leptonyx. Mammal species of the world : a taxonomic and geographic reference (3rd ed.). Baltimore: Johns Hopkins University Press, 2005.

Explaining Glasnost and Perestroika

Explaining Glasnost and Perestroika When Mikhail Gorbachev came to power in the Soviet Union in March 1985, the country had already been steeped in oppression, secrecy, and suspicion for over six decades. Gorbachev wanted to change that. Within his first few years as general secretary of the Soviet Union, Gorbachev instituted the policies of glasnost (openness) and perestroika (restructuring), which opened the door to criticism and change. These were revolutionary ideas in the stagnant Soviet Union and would ultimately destroy it. What Was Glasnost? Glasnost, which translates to openness in English, was General Secretary Mikhail Gorbachevs policy for a new, open policy in the Soviet Union where people could freely express their opinions. With glasnost, Soviet citizens no longer had to worry about neighbors, friends, and acquaintances turning them into the KGB for whispering something that could be construed as criticism of the government or its leaders. They no longer had to worry about arrest and exile for a negative thought against the State. Glasnost allowed the Soviet people to reexamine their history, voice their opinions on governmental policies, and receive news not pre-approved by the government. What Was Perestroika? Perestroika, which in English translates to restructuring, was Gorbachevs  program to restructure the Soviet economy in an attempt to revitalize it. To restructure, Gorbachev decentralized the controls over the economy, effectively lessening the governments role in the decision-making processes of individual enterprises. Perestroika also hoped to improve production levels by bettering the lives of workers, including giving them more recreation time and safer working conditions. The overall perception of work in the Soviet Union was to be changed from corruption to honesty, from slacking to hard work. Individual workers, it was hoped, would take a personal interest in their work and would be rewarded for helping to better production levels. Did These Policies Work? Gorbachevs policies of glasnost and perestroika changed the fabric of the Soviet Union. It allowed citizens to clamor for better living conditions, more freedoms, and an end to Communism.   While Gorbachev had hoped his policies would revitalize the Soviet Union, they instead destroyed it. By 1989, the Berlin Wall fell and by 1991, the Soviet Union disintegrated. What had once been a single country, became 15 separate republics.