Most often it is said that Greenland does not have a large variety of fauna. But actually, Greenland has more than 3000 species! Amazingly, of these some 672 species are insects... and Greenland has 52 native moths and butterflies!
However, it is remarkable that only seven land mammals are said to be native to Greenland. In contrast, the ocean surrounding Greenland is brimming with large sea mammals and many other creatures in all sizes and forms! If you look at the list of birds there are about 235 species of birds, of which 58 are well-established 'breeding birds' in Greenland.
There is a Greenlandic saying "We call Greenland Kalaallit Nunaat, the Greenlanders’ Land. However, in reality it is just as much the Wildlife’s Land."
Greenland's fauna have all adapted to the Arctic climate both on land and in the water.
The polar bear is the biggest predator. In Greenland the polar bear is only a rare visitor to places where people are - it is most often seen in remote hunting grounds in North- and East Greenland. Along with the reindeer, the musk ox is one of the land mammals which one has the greatest chance of seeing. Wolves, arctic foxes, mountain hares and other small land mammals are also found, but are not often seen close to people.
Whales can be seen all over Greenland, particularly during the summer months. It is most common to see fin whales, humpback whales and minke whales, in addition to which species such as the bowhead whale, blue whale and sperm whale also frequent Greenlandic waters.
The land mammals immigrated, just like humans, from Canada several thousand years ago. Both land and sea mammals have always been an important resource for people in Greenland. The animals have played a key role for their means of existence and in terms of their beliefs and outlook on life.
Biologists call the physical, physiological and behavioral traits that help an organism survive in a particular environment "adaptations". Organisms that live in the Arctic must have adaptations to help them survive and raise young despite the periodic extreme cold, persistent winds, short growing seasons and other difficulties posed by their severe environment.
Tundra bumble bees provide a fascinating example of Arctic adaptation. Many insects cease functioning during winter. Since they are poikilothermic or "cold-blooded", insect body temperatures are closely related to the temperature of their surroundings. The chemical reactions necessary for insect movement do not occur at cold temperatures. Tundra bumble bees have developed a dense hair on their bodies which slows heat loss to the air. They also "shiver" their flight muscles to generate heat. This heat is temporarily trapped within their velvet coat. Some bumblebees can keep, their body temperatures 20-30, degrees C (68-86 degrees F) above air temperatures and are easily active while other insects are too cold to move.
Blubber (a extra fat layer underneath the skin of whales, seals and polar bears for example) is an example of an adaptation that makes it possible to survive calling the Arctic Ocean home! Another is countercurrent blood flow - where fluids flow separately rather than it being a single channel flowing back and forth... So for example, in the legs of an arctic fox treading on snow the paws are necessarily cold, but blood can circulate to bring nutrients to the paws without losing much heat from the body. Proximity of arteries and veins results in heat exchange, so that as the blood flows down it becomes cooler, and doesn't lose much heat to the snow. As the blood flows back up through the veins, it picks up heat from the blood flowing in the opposite direction, so that it returns to the torso in a warm state, allowing the fox to maintain a comfortable temperature.
The furry and wax-like coatings of certain tundra plants are adaptations that enable them to resist cold and wind. The fine dense hair around the flowers of the woolly lousewort not only reduces wind chill, but also traps heat from sunlight like the glass of a greenhouse. The flowers are thus surrounded by relatively warm air, sometimes 20 degrees C (34 degrees F) warmer than the environment. This is quite important because the process of cell division necessary for the formation of seeds cannot occur at cold temperatures. In addition, many tundra plants retain rather than shed their dead leaves each year. The dead leaves serve no apparent purpose except to insulate fragile new buds from the wind and cold.
Most living things are made up of 70% water. When water freezes, it expands and forms ice crystals. Repeated freezing and thawing can destroy living tissue. Some fish overcome this problem by producing chemicals within its body that lowers the freezing temperature of cell fluids. Much like the antifreeze we add to the water in our vehicles, the "antifreeze" prevents the formation of large ice crystals within its cells, even at low temperatures. These fish can then survive temperatures of-20 degrees C (4 F) and the complete freezing of some body parts, including their heads, for up to several days.
One of the most obvious adaptations for life in a cold environment is insulating feathers or fur. Most tundra birds and mammals actually have two coats. Birds like the ptarmigan can keep their body temperatures at 40 degrees C (104 degrees F) without increasing their respiration rate, even at air temperatures of-34 C (-29 F). The ptarmigan's white winter feathers (brown during summer) not only help camouflage it in the snow from predators, but radiate less heat back to the frigid air than would dark feathers.
In addition to the insulation provided by feathers and fur, large size and short appendages are adaptations that reduce heat loss and resist cold. Since small animals have more surface area relative to their weight than large animals, they lose heat more quickly. Musk oxen are one of the largest mammals found in the Arctic. An average-sized adult bull may weigh 340 kilograms (750 pounds). Their relatively short legs and inconspicuous tails minimize heat loss. Only a small patch between the musk oxen's' nostrils and lips is hairless. The rest of the body, including the head and ears, are all densely haired. In addition to the animal's long, course, guard hairs is an exceptionally effective insulating layer of the finest wool grown by any mammal. Below -40 c (-40 F), musk oxen lie with their backs or sides to the wind and choose sheltered valleys or slopes during storms. Slow movements conserve energy in winter and reduce the likelihood of overheating during the brief but warm temperatures of summer.
Sources: Wikipedia.org, Nps.gov, Naturinstituttet.gl