As Polar Bears loom ominously in the traveler's mind, I've devoted an entire post to them, here. This post will focus on the other mammals we may encounter. Polar Bear image, below, copyright, Debi Shearwater. 
The abundance of marine mammals was a principle attractant for people to this region historically. Massive harvesting of marine mammals commenced shortly after Svalbard's discovery. Various species were targeted over a period of several hundred years. Bowhead Whales and the Walrus were driven to near extinction. Populations of the Great Whales were greatly reduced. Today, Polar Bears are protected, as are most other marine mammals, although hunting does still take place. On this voyage, we hope to encounter as many species of mammals as possible. The pack ice will be our constant companion. There is nothing in the world that I love more than the sound of ice cracking as either the ship or Zodiac navigates these frigid, productive waters. Music to my ears! Look carefully— for there is a seal on the ice in the image below!
Nineteen species of marine mammals frequent Svalbard, including the Polar Bear, Walrus, five species of true seals and twelve species of cetaceans. Seal species we hope to encounter include: RINGED, BEARDED, HARBOR, HARP and HOODED. The image below, copyright Debi Shearwater, is of three HOODED SEALS at Spitsbergen. The young Hooded Seal shows a blue-black pelage which is maintained for two years. During breeding season (March), male Hooded Seals inflate a nasal sac to display to the females and other males. It is estimated that the global population of Hooded Seals is one million. The Polar Bear is a predator of Hooded Seals.
We shall make Zodiac cruises in search of marine mammals and seabirds. In the image below, someone is happy to spot a WALRUS! Image, below, copyright Vera Simonsson.
Walruses have a disjointed circumpolar distribution. Two subspecies are recognized, one in the Pacific and the other in the Atlantic. There are approximately 200,000 Pacific Walruses and some 20-30,000 Atlantic Walrus. The Svalbard population is thought to be about 2,000. Walrus is a year-round resident at Svalbard. In Svalbard, nearly all Walruses encountered are males. There are females and calves on the east side of Nordaustlandet but most of these walruses remain in the Barents Sea near Franz Josef Land. In recent years, more females have been seen in Svalbard, as they continue to repopulate their former range. Image below, copyright, Adam Rheborg.
Walruses are extremely social animals. They haul out in tight groups on land and usually travel at sea in tight groups as well. Their is significant sexual segregation outside of the breeding season. Solitary individuals can be seen on occasion on the ice or in the water. These are usually adult males. Image below, copyright, Lisa Strim.
Walrus have a narrow ecological niche that limits their distribution. They depend on: 1) the availability of large areas of shallow water with suitable bottom substrate to support a productive bivalve community, 2) the presence of reliable open water over rich feeding areas, particularly in winter when access to feeding ares is limited by ice cover, and 3) the presence of haul out areas in reasonably close proximity to feeding areas. Their main diet is bivalve mollusks, clams of various types, that they search for using their sensitive whiskers. Their ivory tusks were a valuable trade item. Walruses can live to an age of over 40 years. Image below, copyright, Morten Joergensen.
A variety of toothed whales (Odontocetes) can be found in the Svalbard region. These include: BELUGA, NORTHERN BOTTLENOSE WHALE, SPERM WHALE, KILLER WHALE, PILOT WHALE and WHITE-BEAKED DOLPHIN. NARWHAL is a very, very remote possibility.
Folks who have taken pelagic trips from California will be familiar with the Pacific White-sided Dolphin. The WHITE-BEAKED DOLPHIN, above, is a member of that same genus, Lagenorhynchus). This is the most numerous dolphin in the Barents Sea. Image above, copyright, Troels Jacobsen.
The SPERM WHALE is the largest toothed whale, up to 45 tons. Sperm Whales are very deep divers that feed primarily on squid. Female Sperm Whales are highly social and live together with other females and their young. Adult males are usually solitary. Hunting of Sperm Whales began in the early 1880's. Their population was very depleted, especially the large males. There is currently no hunting of Sperm Whales in the north Atlantic region and they are protected in Svalbard. Images of Sperm Whales, above and below, copyright, Don Doolittle.
Several species of baleen whales which we might encounter include: MINKE, HUMPBACK, BLUE, FIN, and rarely, but possibly, BOWHEAD. Minke Whale is the most likely whale we could encounter. However, an encounter with a BLUE WHALE, below, would be unforgettable. Blue Whale is the largest animal ever to have lived on Earth. Sightings in the north Atlantic region are rare, as Blue Whales were hunted to the brink of extinction by commercial whaling. They remain endangered. In fact, worldwide, Blue Whales remain a rare and endangered species. In Svalbard, they are protected. Blue Whale image below, copyright, Don Doolittle.
HUMPBACK WHALES are making a very slow comeback in this region, despite suffering a 90% depletion of their population due to commercial whaling. They are one of the most easily recognized whales, especially their uniquely patterned under tail flukes. Image below, copyright, Debi Shearwater.
The only naturally occurring terrestrial mammals are the ARCTIC FOX and SVALBARD REINDEER. The Arctic Fox has a circumpolar distribution and is found in a wide variety of tundra habitats. In Svalbard, they occur from the highest mountain ridges to the coast, and even on pack ice. Arctic Foxes are especially abundant in areas where food are readily obtained, such as the west coast of Svalbard where large numbers of seabirds, eiders and geese breed. They are commonly seen around the town of Longyearbyen. So, be alert! Arctic Fox image, below, copyright, Don Doolittle.
The SVALBARD REINDEER is a small subspecies of Rangifer tarandus. Males are significantly larger than females and have larger antlers. Svalbard Reindeer are short-legged and have relatively short, round heads. They are well insulated against the cold winter. These reindeer exhibit a very sedentary behavior which reduces their energy demands. They have a well developed ability to use their own reserves, both fat and muscle tissue, when access to food is poor in winter. They are commonly seen in town at Longyearbyen. Oh, and no, that is not a reindeer, below! It is a lemming which I photographed near Hudson Bay, Churchill, Canada. It is the closest image I have of an introduced animal that is found in Svalbard— the SIBLING VOLE. 
The SIBLING VOLE is a microtus that was accidentally brought to Svalbard with hay shipments that came from Russia to feed horses. Sibling Voles have been observed regularly near Longyearbyen since the 1960s. It is active throughout the winter. They have a very high reproductive rate and good dispersal abilities. The Sibling Vole in Svalbard has no natural competitors and its only predator is the Arctic Fox.
Join me in the search for Svalbard's mammals and birds on Shearwater Journeys' charter voyage on board M/S Stockholm, July 8 - 18, 2013!
Walrus forever,
Debi Shearwater
debi@shearwaterjourneys.com
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