Map of the Bering Sea and Aleutian Islands

THE BERING SEA

The Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves.

The Bering Sea is separated from the Gulf of Alaska by the Alaska Peninsula. It covers over 2,000,000 square kilometres (770,000 sq mi) bordered on the east and northeast by Alaska, on the west by Russia's Far East and Kamchatka Peninsula, on the south by the Alaska Peninsula and the Aleutian Islands and on the far north by the Bering Strait, which connects the Bering Sea to the Arctic Ocean's Chukchi Sea. Bristol Bay is the portion of the Bering Sea which separates the Alaska Peninsula from mainland Alaska. The Bering Sea is named for Vitus Bering, a Danish navigator in Russian service, who in 1728 was the first European to systematically explore it, sailing from the Pacific Ocean northward to the Arctic Ocean.

The Bering Sea ecosystem includes resources within the jurisdiction of the United States and Russia, as well as international waters in the middle of the sea (known as the "Donut Hole"). The interaction between currents, sea ice, and weather makes for a vigorous and productive ecosystem.

THE BERING STRAIGHT

The Bering Strait (Russian: Берингов пролив, Beringov proliv, Yupik: Imakpik) is a strait 82 kilometres (51 mi; 44 nmi) wide at its narrowest point, between Cape Dezhnev, Chukchi Peninsula, Russia, the easternmost point (169° 43' W) of the Asian continent and Cape Prince of Wales, Alaska, USA, the westernmost point (168° 05' W) of the North American continent. Named after Vitus Bering, a Russian explorer born in Denmark, it lies slightly south of the polar circle at approximately 65° 40' N latitude, with the present US-Russia east-west boundary, agreed to only by the USA, at 168° 58' 37" W.

The Strait has been the subject of scientific speculation that humans migrated from Asia to North America across a land bridge known as Beringia when lower ocean levels – perhaps a result of glaciers locking up vast amounts of water – exposed a wide stretch of the sea floor, both at the present strait and in the shallow sea north and south of it. This view of how paleo-indians entered America has been the dominant one for several decades and continues to be the most accepted one.

As of 2014, the Russian coast of the Bering Strait has been a closed military zone since 2012. Through organised trips and the use of special permits, it is possible for foreigners to visit. All arrivals must be through an airport or a cruise port. Unauthorized travelers who arrive on shore after crossing the strait, even those with visas, may be arrested, imprisoned briefly, fined, deported and banned from future visas.

The Bering Strait is approximately 82 kilometres (51 mi; 44 nmi) wide at its narrowest point, with depth varying between 30 metres (98 ft) and 50 metres (160 ft). It connects the Chukchi Sea (part of the Arctic Ocean) to the north with the Bering Sea (part of the Pacific Ocean) to the south.

The International Date Line runs equidistant between the Strait's Diomede Islands at a distance of 1.5 km (1 mi), leaving the Russian and American sides usually on different calendar days, with Cape Dezhnev 21 hours ahead of the American side (20 hours during daylight saving time).

The Humpback whale is one of the most prolific cetaceans to frequent these rich feeding grounds, also one of the most playful. Broaching is a spectacular treat for visitors. Kulo Luna is shown above as a calf.

BIODIVERSITY

The sea supports many endangered whale species including Bowhead Whale, Blue Whale, Fin Whale, Sei Whale, Humpback Whale, Sperm Whale and the rarest in the world, the North Pacific Right Whale. Other marine mammals include walrus, Steller Sea Lion, Northern Fur Seal, Beluga, Orca and polar bear.

The Bering Sea is very important to the seabirds of the world. Over 30 species of seabirds and approximately 20 million individuals breed in the Bering Sea region. Seabird species include Tufted Puffins, the endangered Short-tailed Albatross, Spectacled Eider, and Red-legged Kittiwakes. Many of these species are unique to the area, which provides highly productive foraging habitat, particularly along the shelf edge and in other nutrient-rich upwelling regions, such as the Pribilof, Zhemchug, and Pervenets canyons. The Bering Sea is also home to colonies of Crested Auklets, with upwards of a million individuals.

Two Bering Sea species, the Steller's Sea Cow (Hydrodamalis gigas) and Spectacled Cormorant (Phalacrocorax perspicillatus), are extinct because of overexploitation by man. In addition, a small subspecies of Canada goose, the Bering Canada goose (Branta canadensis asiatica) is extinct due to overhunting and introduction of rats to their breeding islands.

The Bering Sea supports many species of fish. Some species of fish support large and valuable commercial fisheries. Commercial fish species include 6 species of Pacific Salmon, Alaska Pollock, Red King Crab, Chionoecetes Pacific cod, Pacific halibut, Yellowfin Sole, Pacific ocean perch and sablefish.

Fish biodiversity is high, and at least 419 species of fish have been reported from the Bering Sea. The Bering Sea is world renowned for its enormously productive and profitable fisheries, such as King Crab, opilio and tanner crabs, Bristol Bay salmon, pollock and other groundfish. These fisheries rely on the productivity of the Bering Sea via a complicated and little understood food web. The continued existence of these fisheries requires an intact, healthy, and productive ecosystem.

Commercial fishing is big business in the Bering Sea, which is relied upon by the largest seafood companies in the world to produce fish and shellfish. On the U.S. side, commercial fisheries catch approximately $1 billion worth of seafood annually, while Russian Bering Sea fisheries are worth approximately $600 million annually.

The Bering Sea also serves as the central location of the Alaskan king crab and Opilio crab seasons, which are chronicled on the Discovery Channel television program Deadliest Catch. Landings from Alaskan waters represents half the U.S. catch of fish and shellfish.

THE ALEUTIAN ISLANDS

The Aleutian Islands (/əˈl(j)uːʃən/; possibly from Chukchi aliat, "island") are a chain of 14 large volcanic islands and 55 smaller ones belonging to both the United States and Russia. They form part of the Aleutian Arc in the Northern Pacific Ocean, occupying an area of 6,821 sq mi (17,666 km²) and extending about 1,200 mi (1,900 km) westward from the Alaska Peninsula toward the Kamchatka Peninsula in Russia, and mark a dividing line between the Bering Sea to the north and the Pacific Ocean to the south. Crossing longitude 180°, at which point east and west longitude end, the archipelago contains both the westernmost part of the United States by longitude (Amatignak Island) and the easternmost by longitude (Semisopochnoi Island). The westernmost U.S. island in real terms, however, is Attu Island, west of which runs the International Date Line. While nearly all the archipelago is part of Alaska and is usually considered as being in the "Alaskan Bush", at the extreme western end, the small, geologically related Commander Islands belong to Russia.

The islands, with their 57 volcanoes, are in the northern part of the Pacific Ring of Fire. Physiographically, they are a distinct section of the larger Pacific Border province, which in turn is part of the larger Pacific Mountain System physiographic division.

Unalaska

The islands, known before 1867 as the Catherine Archipelago, comprise five groups (east to west):

* The Fox
* Islands of Four Mountains
* Andreanof
* Rat; and
* Near.

All five are located between 51° and 55° N latitude and 172° E and 163° W longitude. The largest islands in the Aleutians are Attu (the furthest from the mainland), and Unalaska, Umnak, and Akun in the Fox Islands.

The axis of the archipelago near the mainland of Alaska has a southwest trend, but near 179° its direction changes to the northwest. This change of direction corresponds to a curve in the line of volcanic fissures that have contributed their products to the building of the islands. Such curved chains are repeated about the Pacific Ocean in the Kuril Islands, the Japanese chain, and in the Philippines. All these island arcs are at the edge of the Pacific Plate and experience much seismic activity, but are still habitable; the Aleutians lie between the Pacific and North American tectonic plates. The general elevation is greatest in the eastern islands and least in the western. The island chain is a western continuation of the Aleutian Range on the mainland.

The great majority of the islands bear evident marks of volcanic origin, and there are numerous volcanic cones on the north side of the chain, some of them active; many of the islands, however, are not wholly volcanic, but contain crystalline or sedimentary rocks, and also amber and beds of lignite. The coasts are rocky and surf-worn, and the approaches are exceedingly dangerous, the land rising immediately from the coasts to steep, bold mountains.

These volcanic islands reach heights of 6,200 feet (1,900 m). Makushin Volcano (5,691 feet (1,735 m)) located on Unalaska Island, is not quite visible from within the town of Unalaska, though the steam rising from its cone is visible on a (rare) clear day. Residents of Unalaska need only to climb one of the smaller hills in the area, such as Pyramid Peak or Mt. Newhall, to get a good look at the snow-covered cone. The volcanic Bogoslof and Fire Islands, which rose from the sea in 1796 and 1883 respectively, lie about 30 miles (50 km) west of Unalaska Bay.

Chapter 7 - ARCTIC CIRCLE  50⁰ N, 170⁰ W

  (extract from: Kulo Luna The $Billion Dollar Whale by Jameson Hunter )

The Arctic region is a vast region of icy seas and snow covered lands where the sun does not set in summer, nor rise in winter. This desolate expanse is home to hardy Eskimos, a race of superbly adapted nomadic aboriginal flesh eaters, polar bears and seals. Around the North Pole, the waters are permanent sheet or pack ice. Further south, the ice melts in summer, which melt is gradually creeping north as the earth is warming. In winter Eskimos shelter in igloos, in summer in animal skin tents. They live on a mixture of fish, seals and the occasional whale, when meat is plentiful. Their clothes are fashioned from furs and they are skilled artisans.

Further south at the rim of the Bering Sea, the Aleutian Islands are the feeding grounds for the humpback whale, giant rorqual acrobats and accomplished vocalists. Humpback whales have strange white patch splashes on their unusually large front flippers and body undersides, presumably as camouflage. The flippers are roughly a third of body length and irregular shaped with round knob like projections on their large upper and lower jaws, and long head. Humpbacks are fond of leaping out of the water in a display called broaching, when their deeply notched tail flukes are a distinguishing feature.  

Humpbacks have widely spaced throat grooves that expand in billows fashion to allow them to intake large volumes of water. They have no teeth, but feed by filling their mouths with water containing zooplankton, krill and fish, then filtering out the water, expelling it through flexible baleen strips made of keratin, a strong fingernail like substance, which hang in closely packed rows, curtain fashion from the upper jaw. The small animals trapped in their mouths by this sieving process are then swallowed. Groups of Humpbacks hunt in teams, swimming in circles around a fish shoal making bait balls in a technique known as bubble net feeding. A dozen or so whales work together to harvest the bonanza of shoals. This requires a high degree of intelligence, good timing and communication; the water equivalent of pack hunting.

The lead whale dives first and locates a shoal, then swims around it in a circle releasing air bubbles to create a theoretical spiral curtain. The other whales join the leader from underneath in a tight formation, singing to confuse the fish. The fish are then panicked to swim ahead reluctant to enter the bubble curtain barrier, so swim upwards, followed by the whales who all surface mouths agape to net a concentrated fish mouthful. Using this method the whales can easily take a ton of fish a day.

Humpback whales can vocalise for up to thirty minutes at a time. Each song is complicated and unique when compared to songs from other whales in their group. Clearly, singing is a means of communication. They are the longest most complex sound sequences of any animal, save for the vocalisations performed by humans supported by orchestras in operas. These songs can be heard many miles away and each regional population has its own song, sung only during the breeding season. To sing, the whale vibrates air inside itself, in a chamber of bone, but how they achieve this is a mystery, since they have no vocal chords. The bone chamber appears to be a natural harmonic wind instrument.  

The Greek philosopher Aristotle recognised that whales breathed air and bore live young as far back as 310BC. Cetaceans are divided into two suborders: Odontceti (toothed) and Mysticeti (baleen) whales, with two blowholes on top of their heads. There are 12 baleen species divided into 4 families. Humpbacks are rorqual whales belonging to the ‘balaenopteridae’ family. Mothers are protective of calves which they suckle for 10-11 months weaning at about 12 months. The calves reach maturity at around 5 years. They can weigh up to 45 tonnes and grow up to 19 metres in length. Kulo is considerably heavier, a veritable giant weighing nearly 60 tons. Female Humpbacks typically breed every 2-3 years.

It was early in the fall and the beginning of the annual migration from the Gulf of Alaska to the Philippines. One group of North Pacific humpback whales had already started the 3,500 kilometre journey to warmer waters, a grand summer migration, to complete the reproduction cycle; and a very necessary adventure to allow calves to be born in more comfortable surroundings. Migrations are thought to have developed when the food whales fed on moved to cooler waters as changes in continental drifts and ocean currents took place. whales simply followed the food supply as they moved to polar regions, but habitually returned to warmer sheltered waters to provide a suitable environment to give birth.

Their migrations often extend to 16 to 20,000 kilometres in total in a year, so this is just one small leg of their journey. The young and mature males were always the first to leave the group, eager to mark their territory. The adult females joined in, as a trickle herd, out to stretch their muscles after many months of gorging in the rich feeding grounds that are the trademark of the northern waters. Many land mammals and birds, make long treks to reach seasonal feeding grounds, but these treks are dwarfed by the vast annual journeys made by whales.

The last to leave, is the giant female named Kulo, shadowing her young female friend called Kana. These two whales had been identified and tagged by SPLASH project volunteers (Structure of Populations, Levels of Abundance and Status of Humpbacks). Their names had been given to them after deciphering of their grunts and singing, by a computer sampler linked to a hydrophone. Kulo and Kana had become great friends despite their disparity in size. Kulo was by far the largest whale in the group and a gentle giant, even bigger than her male counterparts. She is very strong and confident and well respected because she is also clever. She has a temper, which very occasionally snaps; then watch out. Many a male humpback taking liberties had been chased, caught and bruised for their troubles. If a human, she’d have been a redhead, Maureen O’Hara.

Kana, is the smallest and youngest of the group, so a slow swimmer, but intent on meeting her sisters at the other end of the migration route. The epic exodus normally lasts from 4 to 8 weeks, depending on the rate of swim and currents. Kulo was in no particular hurry as she set a southerly bearing for the Babuyan Islands, just north of Luzon, in the Philippines. Although of course, she did no know the Island’s name, nor the compass bearing. She just knew the Island by its taste, warm clear, sheltered waters and the feeling of well being when she reached that location.

Humpback whales navigate by sensing Earth’s geomagnetic field. The tissues around their brains contain an iron oxide concentration called magnetite, allowing them to sense gradients. There are many different groups of whales in three populations spread about the globe, each with their own familiar pattern and customs. Some are North Atlantic and others cruise the Southern Hemisphere. Kulo and Kana are from a northern Pacific group, by far the biggest group of whales, making up approximately 60% of the world’s humpback whale population.

Kulo has eaten her fair share of schooling fish and krill and packed it all away in nature’s larder as blubber, which stores and releases energy on demand to sustain these wonderful animals on their travels. As she swam along she thought of all those long summer days chasing and being chased by the adult males, in a ritual as old as time itself, but none the less enjoyable for that. All the while the sun shone, providing the energy for photosynthesis, the basis of nearly all life on earth. This chemical reaction makes the algae bloom aplenty as they manufacture carbohydrates, which in turn provides food for the next in line in the food chain.

Humpback adults can eat up to 2,000 pounds of krill in a single day. Every food chain eventually comes to a halt with the dominant animal it supports, in this case the humpback. Food chains as with any other form of energy conversion are dreadfully inefficient when viewed clinically. When man broke the back of the food chain by growing his own crops, on which to rely, he accidentally improved the efficiency of the supply chain and gave humans a huge advantage over other species. The invention of cooking, further improved the digestive conversion ratio, then man farmed animals intensively, since he had the crops to feed them and control of the environment, to include controlling his meat supply.

But that didn’t matter to our friendly whales. What mattered was when man became master of the oceans and greedy for energy. Whole towns were built up specifically to hunt for whales and the precious oils they could provide. This was before the discovery of petroleum in vast subterranean lakes, fractional distillation and the invention of the motor car. A large whale could be reduced to around 100 barrels of oil at about 10 barrels to the ton, plus other exotic compounds used as perfumes and lubricants, such as ambergris. The oil in the head of the Sperm Whale has such fine lubricating qualities, that only up until recently did NASA use it for their space programme.

At first the herds of these giant gray animals must have seemed an inexhaustible bonanza. But just as with the Bison of North America, slowly but steadily the population dwindled, until many species were on the verge of extinction. For this reason laws were introduced banning whaling, to prevent extinction. The International Whaling Commission was established in 1946 to conserve what stocks remained. An indefinite moratorium on all commercial whaling was imposed in 1982. The Convention of International Trade in Endangered Species of Wild Fauna and Flora, prohibits trade in whale products, formerly used extensively in cosmetics and for ornamental carvings. The measures which are now taken to protect whales, has seen a revival of numbers, but the population is still only about a fifth of the pre-whaling days.

Where the people of Iceland, Japan and China traditionally included whale meat in their diet, the whaling ban has hit them hard. Eskimos still hunt whales in limited fashion, but they are not an industrialised nation, thus the impact on whale stocks is negligible. Very occasionally, Iceland has taken a few whales to a strict quota, but Japan operates large mechanised whaling ships, claiming that whales taken are for scientific research, which many authorities allege, due to the numbers, is in defiance of international treaties. For this reason fisheries protection agencies shadow such ships, to ensure there is no refueling at sea, which is prohibited to in some measure limit hunting locations.

  Purpose designed whaling ships are more readily detectable by their size and shadowed by fisheries authorities and animal rights protection groups. Smaller privately owned fishing vessels are not so easy to keep track of, since they may be general purpose boats, converted from trawlers or other working ships. These opportunistic brigands are more dangerous to Kulo and her group, as they mingle with other marine transport. Advances in marine electronics, such as echo location fish finders and other sonar devices, makes the job of trawler captains that much easier. The problem though for modern whalers, is oddly enough, not one that the Captain Ahabs of yesteryear faced. It is the price of fuel and range limitations of the modern diesel engine powered boat.

Kulo is not thinking of any of these issues which affect the survival of her species. She is happy to be watching her friend Kana stretching her flippers, rising and leaping from the sea and falling back amid a wave of silver froth and slapping her tail flukes, which is a sign of whale happiness. Kulo is thinking of meeting up with her mate Buka, himself a bigger than normal male humpback, who courted her for most of the winter, until finally they had a meeting of minds.

- * -

This website is Copyright © 2024 Bluebird Marine Systems Limited.   The names Bluebird, Bluefish, SeaNet™, Utopia Tristar™ and the blue bird and fish n flight logo are trademarks. All other trademarks are hereby acknowledged.