Beluga whales are small (3 - 5m) toothed whales that inhabit coastal and estuarine areas, often with pack ice, in arctic and subarctic areas of the northern hemisphere. They can be recognized by their white color, prominent rounded melon, stout body shape and lack of dorsal fin.

There are approximately 20, 000 beluga whales inhabiting western Hudson Bay and Churchill River estuary areas. Over 3,000 of these white whales summer in the estuary, moving in and out of Hudson Bay with the tides. Beluga whales are among the most vocal whales in the world.

The beluga is the only whale with a flexible neck. (Their vertebrae remain unfused.) Belugas can swim an average speed of 16 -22 kilometers ( 10 - 13.5 miles) per hour, dive to depths of 600 meters (1,950 feet) and hold their breath for 15-20 minutes. The average life span of a Western Hudson Bay Beluga is 10 years, although some have lived as long as 30! Learn more about the beluga whale here.

 
Orca (Killer) whales have a reputation for ferocity unequalled among the cetaceans. They hunt in packs of 3 to 40 animals, and prey on squid, fish, seabirds, seals and other cetaceans. They dislodge basking seals from ice floes by tipping the floes from below, and attacks on beluga and narwhal are well. known. When killer whales are in the vicinity, other marine mammals reportedly take shelter among the ice floes or in deep fiords.

Colouration is shiny black with distinct white areas on belly, chin, flank and behind the eye. A grey saddle patch, whose shape can be used to identify individuals, is found behind the dorsal fin. Adult males average 6 m in length, but may reach 9 m, while females are smaller reaching 4 to 5 m. As befitting their predatory nature, their teeth are large and number 10 to 12 in each half-jaw. The dorsal fin is prominent, and may reach 2 m in height.

In the Canadian Arctic, they are found from Davis Strait to as far north as Lancaster Sound. Although not seen regularily, they can be sometimes be viewed further out from shore from Chesterfield Inlet. They follow migrating herds of seals and other whales to summering areas, but do not usually arrive until after the pack ice has dispersed. They tend to avoid areas of heavy ice due to their large dorsal fin and, therefore, do not penetrate far into the ice-covered Arctic Archipelago. October finds them migrating southward again in advance of the new ice cover.

There is little information available on numbers, populations, population structure, age of sexual maturity or reproductive rate. Mating occurs from May to July. The gestation period is approximately 16 months and a single calf is born in November or December. Life span is probably 40 to 50 years and groups of killer whales are likely cohesive family units.

Killer whales are not hunted in the Canadian Arctic, except when they can be killed with impunity, due to the fear they inspire in northern communities.

 
The ringed seal is the most abundant, widespread and important seal to the socio-economy of the people in the Northwest Territo-ries. The common name refers to the circular markings on the back of the adult. The scientific name refers to the seal's bristly coat.

The ringed seal is the smallest pinniped in the Canadian Arctic. Newborn pups average 4.5 kg in weight and 65 cm in length. When one year old, they are about 70 per cent of their mature size. The average adult is 135 cm long and weighs about 70 kg. Females tend to be slightly smaller than males.

Primarily solitary, the ringed seals occasionally travel in loosely organized groups. They tend to form aggregates at haul-out areas, such as ice cracks.

Segregation by age occurs in winter when adults remain in preferred breeding habitat under stable ice in bays and fiords and non-breeders are found at the floe edge and move in response to food avail-ability and population pressures. Ringed seals have a varied diet composed primarily of the larger shrimp-like crustaceans, small fish and planktonic krill. Fasting occurs during the breeding, moulting and basking periods.

As with most seals, physiological adaptations, such as a high red blood cell count, the ability to reduce their heartrate from 80 -90 beats per minute to 10 -20, and control over the blood flow to vital organs, have enabled ringed seals to make deep and sustained dives. Feeding dives average 3 minutes with 1-1/2 minutes at the surface. Their maximum diving potential is about 90 m and 45 minutes. Ringed seals dive verti-cally, tail first, rarely exposing their backs.

Breathing holes in ice up to 2-1/2 m thick are maintained by clawing the ice with the forefIippers. Before surfacing, a seal may blow bubbles into the hole to test for predators. The breathing hole is cone-shaped and covered with an ice dome punc-tured by a small vent. If snow drifts over the hole, a lair may be hollowed out of it.

Seal pups are usually born on stable ice in a snow den from mid-March to early April. The female finds a natural snow cave or excavates a birth lair in a snow drift over a breathing hole.

 
The name of the bearded seal refers to its conspicuous moustache of long, white whiskers. The alternate name of "square-flipper" describes the shape of its front limbs. In lnuktitut, it is called "ugjuk". Lacking distinctive colouration, the pelt is dark grey on the back and lighter grey on the belly. The sexes are similar in colour. An annual moult occurs between March and August. Annual growth rings in the foreclaws indicate age. The oldest seal that has been found was 31 years old. The bearded seal is one of the largest seals found in the waters of the Northwest Territories. The average weight of adults is 250 kg and the length averages 235 cm. The blubber and hide layers account for 29 to 39 per cent of its weight.

There are about 300,000 bearded seals in Canada. They are permanent residents of the Arctic and are generally found as solitary individuals in areas associated with moving pack ice, such as leads and polynyas. They maintain breathing holes in areas of thin ice by breaking it with their heads. Their diet consists of bottom dwelling organisms found in the shallower waters of the continental shelf. These include worms, crustaceans, clams, crabs and fish, such as arctic cod, sculpin and flounder. Feeding dives as deep as 220 m have been re-ported.

An undisturbed seal swims with its head and back above the water. When sleeping, it floats vertically. The senses of sight and hearing are good while its ability to smell is fair. They sing long musical underwater songs. Singing activity peaks in April and May. A highly varied vocal repertoire indicates a complex social structure that is not well understood. It may be related to claims of territory and breeding condition. Mating occurs in mid-May with a delayed im-plantation of two months and a gestation period of approximately 11 months.

A single pup is born on the ice at the end of April to early May. Bearded seals are the only north-ern seal with four mammae rather than two. The mother-pup bond is strong during the relatively short 12 to 18 days of the nursing period. The pups are then left on their own. A female may give birth everyone or two years. Sexual maturity is attained at six years of age.

Bearded seals have always been important to the Inuit of the Arc-tic. The tough, flexible hide is valued for utilitarian purposes, such as lines, traces, kayak coverings and kamik (boot) soles.

 
The harp seal has a large horseshoe shaped black band on its back on a background of steel blue or pale grey. The head is dark brown or black. The horseshoe on the adult female's pelt may be less distinct and blotched. Pups have white coats of soft, curly, woolly fur for about 1-1/2 weeks, then they moult into a juvenile coat. The average adult is 170 cm in length and weighs 135 kg. Harp seals are very vocal on the breeding and whelping grounds. Their ability to hear underwater is similar to that of humans in air. Large sensitive eyes are well developed for nocturnal vision and bright light, in air or water. Their sense of smell is less acute.

Harp seals are the third most abundant seal in the world. There are three stocks: the northwest Atlantic, the White Sea and Jan Mayen (north of Iceland). The northwest Atlantic population numbers about 1.3 million. These seals whelp in the Gulf of St. Lawrence and offshore Newfoundland. After moulting in April, they migrate northward and spend the summer around Greenland and in the eastern arctic islands of the Northwest Territories. The southward migration begins in September.

The harp seal's diet is primarily marine fish and crustacean macroplankton. Young seals feed in the surface waters while adult harps dive deeper for cod and herring. One seal consumes about 450 kg of fish annually, arctic cod being their most important food. Intense feeding occurs during summer and winter while less feeding occurs during spring and fall migration, whelping and moulting.

The few predators that take harp seals are polar bears, killer whales, sharks and humans. Other causes of mortality are decreases in food by large scale capelin fisheries, discarded net-ting, and oil pollution.

Harp seals live up to 40 years of age. They are sexually mature at 6 years of age. Courtship displays are elaborate, and fighting with teeth and flippers is common. Mating is promiscuous and occurs in late March about two weeks after the pups are born. The mother's milk is rich in butterfat enabling the pup to grow rapidly for the first two weeks, after which the pup is abandoned by the mother. Restlessness and hunger lead them into the water where they begin feeding on krill and start moving northward.

 
Walrus belong to the same order as seals and sea lions. All three are called "pinnipeds," which refers to their webbed, fin-like feet. But though there are many species of seals and sea lions in the world, there is only one species of walrus. It is composed of two subspecies: the Atlantic walrus and the Pacific walrus. The latter is found off the shores of eastern Russia and Alaska, and tends to be somewhat more robust and have larger tusks than the Atlantic walrus, which occurs in the arctic waters of eastern Canada, Greenland, Norway, and western Russia. The adult male walrus may attain a length of 3.6 m and a weight of 1400 kg, becoming considerably more massive in the neck and chest area than the female, which grows to 3.0 m and 900 kg. Walrus' bodies are rather bulky with numerous folds and wrinkles, and a sparse covering of light brown hair, which is moulted every summer and gradually lost in old age. The skin is generally a medium cinnamon to light grey colour with older animals becoming increasingly lighter. The head is comparatively small, with a blunt snout and a set of whiskers, or vibrissae, 10-12 cm long. One of the most distinguishing features of the walrus is the large canine teeth, or tusks, which protrude from the upper jaw. They can reach a length of 60 cm and a basal girth in excess of 26 cm. Both sexes are equipped with tusks, but those of the males tend to be longer and heavier. Since sea water conducts heat about twenty times faster than air, marine mammals must be well insulated to prevent critical heat loss. A thick tough hide and a thick layer of blubber protect walrus from the cold arctic seas. Walrus also have a special thermo-regulation system. When an animal is warm, its blood is shunted to the outer skin and blubber, allowing it to cool off. When immersed in water, the blood is kept from the skin and blubber, thereby conserving vital body heat.

The vibrissae, or whiskers, of the walrus are used to sense food organisms on the sea bottom. Through oral suction they remove the siphons and feet of clams and mussels, and extract the soft bodies of snails from their shells. Their principal prey is bivalve molluscs, but walrus also take various sea worms, crabs, snails, squid, fish and other benthic organisms in lesser quantities if their preferred food is sparse. On occasion walrus have also been known to feed on seals, which they have either killed or found dead. However, this behaviour, according to Inuit, is more characteristic of older, rogue males.

Despite popular belief, walrus do not use their tusks to dig up clams. Their primary role appears to be social, much like antlers on caribou, a signal of social rank. The larger the tusks and body, the higher the animal usually is in the hierarchy. Tusks are used by both males and females in aggressive displays and to defend themselves and their calves. In addition, they are used to create breathing holes in the ice, and to assist in hauling themselves onto the ice. Their sight is poorly developed and, therefore, they must depend mainly on smell and hearing to detect danger.

Locomotion on land and ice is very ungainly, consisting of a shuffling, humping motion. As a result walrus are seldom found far from the water. There they are very agile for their size, attaining speeds of up to 10 km/hr. They may travel considerable distances from land or ice and on occasion have even been found asleep in the water. Gregarious when hauled out, their land uglit can exceed several hundred animals. On ice pans groups tend to be smaller, although many groups may be present in the same area.

Sexual maturity first occurs at 4 years of age in females and 6 in males. The males are polygamous and may form loose harems during the breeding season of April and May. The average length of gestation is 376 days, with calving occurring sometime between April and early May. A single calf is born on the ice and accompanies the female for up to 3 years. Young walrus are completely dependent on milk throughout the first year and are not weaned until the latter part of the second year. Females will breed every other year once mature; however, they tend to become less fertile in their later years.

 
Source: NWT Wildlife Sketches, Northwest Resources Wildlife and Economic Development