Addendum K. Wild Arctic Station, the Franklin Research Institute
Welcome to Wild Arctic Station: looks like you made it safely here after that somewhat hazardous ride here. On behalf of the Franklin Research Institute, studying some of the animals that live here, let me point out a few facts. First of all, my name is BERT, and I am one of the researchers stationed here. I will say a few words, answer any questions you might have, and send you off to view the other exciting animals that we have here at Wild Arctic Station.
Before I launch into my talk on the animals, let me point out a few safety considerations for the personal well being of yourself and the animals that live here.
Be conscious of any “loose” items you have: that includes keys, sunglasses, cell phones, digital cameras, and any other “objects” that are valuable to you. If they should happen to fall into the water, it will take a lot of excitement, concern, coordination, and time in order to recover; just be super careful.
This means that you should not sit or stand on the ledge of the railings.
Any food or drinks that you have should have already been discarded before you entered into the “exciting ride” here.
In this Beluga exhibit, there are 3 of these white whales. Ferdinand, Ruby, and Allua, with the male weighing in around 2000 pounds, nearly 13.5 feet long, and the two females are each about 1300 pounds, and Ruby is 11.4 feet long while Allua is shorter at nearly 11 feet long. Ferdinand is 37 years old, Ruby 29, and Allua is the youngest at around 23 years of age.
The Beluga whales here are true whales, belonging to the group called Cetacea, all of which are large aquatic mammals that have forelimbs modified into flippers, a tail that is flattened horizontally, a nostril at the top of the head for breathing (called a blowhole), and no hind limbs externally. This group contains all the whales, dolphins, and porpoises. This group is further subdivided, based on whether they have teeth (and thus eat larger animals) or whether they have a filtering, comb-like structure called a baleen, which allows these to eat smaller, shrimp like animals. The Beluga is in the former group.
The Beluga’s closest relative is the narwhal, which also lives in the
Belugas are found in shallow coastal waters, often in waters barely deep enough to cover their bodies. You can see that the absence of a dorsal fin is of advantage to these whales, as they skim just below the ice in search of breathing openings; they are also one of the only whales that can swim both forward and backward, which allows them to get into enclosed waters from which they can “back out” and free themselves.The lack of a dorsal fin also means that they have less surface area for the loss of body heat, which assists them in their thermoregulation.
The world population of Belugas is estimated to be about 60,000-80,000 animals.
The colors of a Beluga whale is dark gray to bluish or brownish gray when first born, becoming darker after the first month or so. Thereafter, they gradually become paler, due to the lessening of black color pigments in their skin. As adults, they are the stunning white that you see in our 3 Belugas.
The melon is a rounded structure on the top/dorsal part of the whale’s head, just in front of the blowhole. You can observe that the melon is very prominent and hangs over the rostrum/nose area. This melon is composed of fats. It is known that the melon facilitates sound production, as it changes shape when the whale is producing sounds.
The blowhole is single, and it is covered by a muscular flap. The flap provides a water-tight seal, so that when the animal is swimming underwater, no water enters the blowhole. When the animal gets to the surface and needs to “breathe,” it then can force the flap to open so that it can exhale and inhale.
Beluga whales have a well developed sound reception system, acute vision both in and out of the water, a social sense of touch as they are known to seek out other Belugas for physical contact.
In general, Belugas are slow swimmers. They commonly swim around 2-6 mph, but are capable of sustaining a maximum speed of over 13 mph for as long as 15 minutes. They are highly maneuverable rather than being high speed swimmers.
Since the Belugas live and feed on fishes primarily in shallow waters, they do not need to dive to deep depths nor stay submerged for long periods of time. But, under experimental conditions, they have been made to dive down to depths deeper than 2000 feet, and though most of their dives are less than 10 minutes, they can stay under for more than 15 minutes.
Belugas, like the other whales, are well adapted for the marine world. They contain blubber for insulation, which allows them to maintain their warm-bloodedness as a mammal. In order to make their diving periods be extended, the heart rate slow down, thus requiring less energy, once they submerge.
Blood is shunted away from the peripheral areas and confined to the internal, vital organs, so that those organs are well oxygenated during a dive. The muscle areas do contain a second type of respiratory pigment called myoglobin, which serves as a storehouse of oxygen that can be released in the course of an extended dive once the original supply of oxygen becomes diminished since that is not replenished by more blood.
One very interesting part of the physiology of a Beluga whale, as is true for most of the other whales, is that while it sleeps, it only goes through deep sleep in one hemisphere of the brain at a time.
Can anyone tell me what a group of whales are called? Yep, a pod is a cohesive social unity, containing 2 or more animals, usually up to 25 individuals. The average pod size in Belugas is around 10.
One of the most common Beluga behaviors is vocalizing. They rely on sound production and reception to navigate, communicate, locate breathing holes, and hunt in dark and/or murky waters. At least 11 different vocal sounds produced by Belugas have been documented, including high pitched, resonant whistles and squeals, clucks, mews, chirps, trills, and bell like tones. There is a demonstration in this exhibit hall that allows you to hear some of these sounds. Since the larynx of toothed whales do not have vocal cords, the sounds are produced by movements of air between nasal sacs in the blowhole region.
Beluga whales are opportunistic feeders. This means that they can prey upon more than 100 different kinds of primarily bottom-dwelling animals, such as octopi, squids, crabs, snails, sandworms, and fishes such as cod, herring, smelt, and flounder. Here at Sea World, they are fed frozen fish, but their diet is varied to include squid as well. They eat approximately 3% of their body weight per day, which means these receive about 50 pounds per day.
Beluga whales probably live 25-30 years in the wild; the ones here at Sea World are older than most Belugas in nature, and they appear to be very healthy.
Having Beluga whales at Sea World provides us with the opportunity to learn about the animals and how human activities impact their survival. In the protected environment of Sea World, scientists can examine aspects of their biology that are difficult or impossible to study in the wild.
For those of you who want a special interaction with Belugas, stop off at the Wild Arctic Gift Shop before you leave this exhibit and inquire about this special program that has just recently been introduced. You will have a chance to be with the trainer and animal care person by the poolside, touch the belugas, and have this very special once in a lifetime experience that you cannot get out in the wild.
The Wild Arctic adventure, however, does not stop with the Beluga whales. As you continue through the exhibit, you will come face to face with polar bears and walruses.
Polar bears are found throughout the
v Polar bears, like all other Carnivores, which include bears, dogs, cats, raccoons, otters, and weasels, have well developed claws, strong facial musculature, and specialized teeth. The canines are long, sharp, and well developed.
v Polar bears are among the largest land carnivores, comparable in size to the grizzly bear. Male polar bears grow 2-3 times larger than the females (males between 8-10 feet long and weigh 600-1300 pounds; females 6-7 feet long and 330-660 pounds). The 3 that are here at Sea World are all 12 years old (2007) and include Charly, over 1000 pounds and the lone male, and Snowflake and Szenja, each around 625 pounds. At birth, cubs weigh only about a pound and a half!
v They live in an exhibit area of around 90000 gallons, with a depth of 12 feet, as compared to the area of the beluga habitat of 460,000 gallons and 18 feet in depth. The walrus habitat contains 120,000 gallons at a depth of 16 feet, but most of the time, you will see the walruses playing in the shallow ledge right next to the acrylic panel.
v The Polar Bears are fed about 8-20 pounds of food per day for each of them. Their diet includes meat, fish, biscuits, fruits, vegetables, and a variety of other foods.
v The skin of polar bears is black, with the fur being translucent, although often mistaken for being white. The fur provides insulation and camouflage.
v The sharp claws and stiff hairs on the pads of its paws provide good traction on ice.
v The polar bear has a short tail and small ears that help reduce heat loss, as well as its relatively small head and long, tapered body for streamlining while swimming.
v It depends mainly upon the pack ice and the marine food web for survival. It is circumpolar in and around the
v It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, but will eat anything it can capture, including birds, rodents, shellfish, crabs, beluga whales, young walruses, and an occasional musk oxen or reindeer.
v Orcas are their main predators in their environment.
v Polar bears are crafty hunters and will wait by the breathing holes of the seals (which are their main food) in the ice for them to surface. Sometimes they will crawl up to sleeping seals, stopping if the seal wakes, then resuming only to finally leap to catch them.
v Global warming leads to the melting of the sea ice on which the polar bears are heavily dependent.
v The longevity in nature is unknown, but they can live for more than 40 years in captivity.
The third large marine mammal you will observe in the Wild Arctic Exhibit is the walrus. There are 4 of them here: Obie, the only male, by far the largest at 3400 pounds, and 20 years old; Kitkatska is the large female, weighing 1750 pounds and is 26 years old; the 2 pups are both females, Tessa, born in 2004, and weighing 260 pounds, and Bocce, born in 2005, and weighing 120 pounds. You might not see these 2 pups all the time as they are secretive and not as bold as Obie or Kitkatska.
Those of you who have gone to Pacific Point, with the narration given for the seals and sea lions probably were informed that the order Pinnipedia, which means “fin footed animals”, contain the seals, sea lions, and the walrus. Morphologically, the walrus more closely resembles the true seals, like the harbor seal, whereas in behavior, they are more like the sea lions, or the eared seals. There are 2 subspecies of the walrus, which are geographically isolated from each other. One lives in the Pacific Ocean, like the ones we have here at Sea World, while the other is found in the
Distribution and habitat:
Walruses are circumpolar, but they are concentrated in geographically separate areas, with little or no chance of interbreeding.
The Pacific forms inhabit the Bering, Chukchi, and
Most walruses live where the air temperature is about 5-41 degrees.
They are found where the water temperature is o more than 260 feet deep.
They prefer a habitat with a gravelly bottom. They spend 2/3 of their lives in the water, but they do haul out to rest and to bear their young.
Walruses are adapted to a habitat of sea ice and prefer snow covered moving pack ice or ice floes to land. They haul out on small rocky islands when ice is not present.
The walrus migrates following the extent of the ice pack. Throughout the year, they occur primarily in or near the southern periphery of the pack ice. They migrate primarily by swimming, but they have been observed riding the ice floes as well. Some of them are known to migrate for more than 1800 miles each year.
The total estimated population in the world is about 250,000 animals, with the Pacific form containing most of that, estimated at 200,000 in 1990. This form has been hunted to depletion and allowed to recover several times. After the last depletion in the 1930s, walruses were given protection by
By the early 1980s, Pacific walruses appeared leaner. They increased their consumption of alternate foods such as fishes. Natural mortality increased, and birth rates decreased. This evidence suggests that the Pacific walrus population may have approached the carrying capacity of its environment.
Physical characteristics:
The males weigh about 1700-3700 pounds, and they are about 9-12 feet long.
Females are slightly smaller, weighing 880-2750 pounds and lengths of 7-10 feet.
The Atlantic forms are slightly smaller, with males weighing about 2000 pounds and lengths up to 8 feet.
A walrus has a rounded, fusiform body.
Their coloration is cinnamon brown overall. They appear quite pale in the water; after a sustained period in very cold water, they may appear almost white. They are pinkish in warm weather because the tiny blood vessels in the skin dilate and circulation increases. This increased circulation sheds excess body heat.
Calves at birth are ash gray to brown. Within a week or two, calves become tawny brown. The coloration pales with age, so that the younger individuals are darker.
Their limbs are adapted as flippers, which are hairless. The skin on the soles of a walrus’s flippers is thick and rough, providing good traction on land and ice.
The foreflippers/pectoral flippers have all the major skeletal elements of the forelimbs of terrestrial mammals, but the arm bones are shortened and modified. Each foreflipper has 5 digits of about equal length, and each digit has a small and inconspicuous claw. While swimming, the walrus holds its foreflippers against its body or uses them for steering. On land, a walrus holds its foreflippers at right angles to the body for walking.
They have triangular shaped hind flippers. The hind flippers also have 5 bony digits. The claws on the middle 3 digits are larger than the two outer claws.
The walrus uses alternating strokes of their hind flippers to propel themselves in the water, much like the true seals.
However, like the sea lions/eared seals, the walrus can rotate their hind flippers under their body, enabling them to walk on all fours.
A walrus’ head is square and broad, with conspicuous tusks and whiskers/vibrissae. There are 400-700 vibrissae in 13-15 rows on the snout. Vibrissae are attached to muscles and are supplied with blood and nerves, and are especially sensitive to touch.
Most walruses have 18 teeth, with the 2 canines in the upper jaw modified into long, ivory tusks. Both the males and females have tusks. Those of the male tend to be longer, straighter, and stouter than those of the females. These tusks can grow to lengths of more than a yard (39 inches in males, 32 inches in females). The primary functions of the tusks appear to be in establishing social dominance and for hauling out onto ice or rocky shores.
Like the seals, there are no external ear flaps, just an auditory opening.
The paired nostrils are located on the snout above the vibrissae, and they remain closed during the dive in the resting state.
A walrus’ skin is thick and tough. It may reach a thickness of more than 1 ½ inches, being thickest on the neck and shoulders of adult males, where it protects the animal agains jabs by the tusks of other walruses.
Hair is about ½ inch long over most of the body, being shortest on the face and absent on the flippers. They thin out with advancing age.
Senses:
v A walrus’ hearing is probably sensitive. Eskimos imitating walrus sounds have obtained responses from walruses more than a mile away.
v Their eyesight is probably not as acute as those of the seals and sea lions. This is probably due to their feeding on bottom-dwelling animals, where acute vision is not necessary for survival.
v Walruses seek out physical contact with other walruses. The vibrissae are extremely sensitive tactile organs, and studies indicate that a walrus can discriminate the shape and size of an object using those vibrissae.
v Walruses prefer certain foods, but researchers do not know how acute the sense of taste is or how important it is in food preference. Walruses have fewer taste buds on their tongues than terrestrial mammals.
v The sense of smell in air is well developed. It probably functions in the mother/calf recognition, for sensing approaching predators, or for sensing other walruses while hauled out.
Adaptations for the aquatic environment:
Ø Normal swimming speed for walruses is about 4 mph, but they can make short bursts of more than 20 mph.
Ø They normally breathe at the surface for about 1 minute after every 5-8 minute dives. They can stay submerged for about 10 minutes.
Ø Because their prey usually inhabit waters no more than about 250 feet deep, a walrus generally dives no deeper than that. However, deeper dives have been documented.
Ø Like the other marine mammals, they have other special physiological adaptations for diving, such as increased blood volume, increased concentrations of myoglobin in the muscles, peripheral shunting of the blood,
and slowing of the heart rate when submerged.
Ø Walruses thermoregulate with the presence of blubber and the shunting or dilation of peripheral blood vessels.
Behavior:
Walruses are among the most gregarious of animals. They exhibit social behavior all year and congregate by the hundreds. They haul out in herds, seldome hauling out alone, with the males and females forming separate herds.
Social dominance is well established in herds and subgroups. Dominance is established by tusk length, body size, and aggressiveness. The largest walrus with the longest tusk is the most aggressive and generate threat displays most often.
A male will fight with another male if it intrudes upon him during a courtship display. These fights often result in physical injury, and the frequent scars and lacerations are visible on the necks and shoulders of adult males after the breeding season. The males produce bell like sounds and other vocalizations as part of a courtship display.
Walruses can produce sounds both above and below the water. They are among the most vocal of the pinnipeds, producing growls, taps, knocks, grunts, barks, soft whistles, rasps, and clicks.
Food and foraging:
o Walruses prefer mollusks, mainly bivalves such as clams. They also eat many other kinds of benthic invertebrates, including worms, gastropods/snails, cephalophods/octopi and squid, crustaceans/shrimps, sea cucumbers, and other soft bodies animals. They may occasionally prey on fishes such as cods.
o They may feed on the carcasses of young seals when food is scarce. There are some rare but habitual seal eating walruses, with their diet consisting of ringed and bearded seals. These are usually male walruses, recognizable because they are usually larger than other males, with powerful shoulder and chest muscles. Their skin may become grease stained from the blubber of the seals they prey on.
o These walruses each eat between 60-100 pounds of fish, clams, and squid per day.
o In the seas, they sometimes catch fish, but generally graze along the sea bottom for clams, which they suck from the shell. But their diet also includes shrimp, crabs, tube worms, soft coral, tunicates, sea cucumbers, various other mollusks, and even parts of other pinnipeds. They use the vibrissae to locate food. A walrus moves its snout along the bottom, rooting through the sediment and using those vibrissae to help detect prey. Abrasion patterns of the tusks show that they are dragged through the sediment but are not used to dig up the prey.
o They may also take in mouthfuls of water and squirt powerful jets at the sea floor, uncovering and excavating burrowing invertebrates such as clams.
o The walrus does not chew its food, but they do sometimes crush clam shells.
o Their predators are mainly orcas and polar bears, although the larger walruses are known to have killed polar bears.
o Walruses are known to live around 50 years.
o The gestation period is 15-16 months, with the calving taking place usually on the ice. Newborn calves are about 99-165 pounds, about 3-4 feet long. They nurse for 2 or more years. Here at Sea World, the calves nurse 6-10 times per day, and they are fed a formula of cream, ground fish, and clams, milk replacer, vitamins, and water, if the female is not present. Growth rates are such that they gain nearly 2 pounds daily here at Sea World.
o Walruses live to a maximum of about 40 years.
This Wild Arctic Exhibit/the Franklin Research Institute opened in 1997, and it has proven to be one of the most popular exhibits here at Sea World.
Once more, Sea World thanks you for your patronage, as your admission dollars go toward supporting our studies of these marine mammals in a way that is most difficult to duplicate in nature, and much of what we know about the biology of these animals have come about from our interaction with them.
Let me remind you once again about that special treat of being able to interact with the Beluga whales down at the water’s edge, just as the trainer is doing. Just inquire at the Wild Arctic Gift Shop for details and how you can make the arrangements to be able to do this. This especially applies to those of you with annual Passports, who come repeatedly to Sea World and want closer interaction with some of these animals, but in an entirely safe and most satisfying way. Once you stroke or feed a Beluga whale, you will never be the same, unconcerned person about their welfare in their native Arctic habitat!
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