Brief Description
Located well above the Arctic Circle, the site includes the mountainous Wrangel Island (7,608 km2), Herald Island (11 km2) and surrounding waters. Wrangel was not glaciated during the Quaternary Ice Age, resulting in exceptionally high levels of biodiversity for this region. The island boasts the world’s largest population of Pacific walrus and the highest density of ancestral polar bear dens. It is a major feeding ground for the grey whale migrating from Mexico and the northernmost nesting ground for 100 migratory bird species, many endangered. Currently, 417 species and subspecies of vascular plants have been identified on the island, double that of any other Arctic tundra territory of comparable size and more than any other Arctic island. Some species are derivative of widespread continental forms, others are the result of recent hybridization, and 23 are endemic.
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Justification for Inscription
Criterion (ix): The Wrangel Island Reserve is a self-contained island ecosystem and there is ample evidence that it has undergone a long evolutionary process uninterrupted by the glaciation that swept most other parts of the Arctic during the Quaternary period. The number and type of endemic plant species, the diversity within plant communities, the rapid succession and mosaic of tundra types, the presence of relatively recent mammoth tusks and skulls, the range of terrain types and geological formations in the small geographic space are all visible evidence of Wrangel’s rich natural history and its unique evolutionary status within the Arctic. Furthermore, the process is continuing as can be observed in, for example, the unusually high densities and distinct behaviours of the Wrangel lemming populations in comparison with other Arctic populations or in the physical adaptations of the Wrangel Island reindeers, where they may now have evolved into a separate population from their mainland cousins. Species interaction strategies are highly-honed and on display throughout the island, especially near Snowy owl nests which act as protectorates for other species and beacons for migratory species and around fox dens.
Criterion (x): The Wrangel Island Reserve has the highest level of biodiversity in the high Arctic. The island is the breeding habitat of Asia’s only Snow goose population which is slowly making a recovery from catastrophically low levels. The marine environment is an increasingly important feeding ground for the Gray whale migrating from Mexico (some from another World Heritage site, the Whale Sanctuary of El Vizcaino). The islands have the largest sea-bird colonies on the Chukchi Sea, are the northernmost nesting grounds for over 100 migratory bird species including several that are endangered such as the Peregrine falcon, have significant populations of resident tundra bird species interspersed with migratory Arctic and non-Arctic species and have the world’s highest density of ancestral polar bear dens. Wrangel Island boasts the largest population of Pacific walrus with up to 100,000 animals congregating at any given time at one of the island’s important coastal rookeries. Since Wrangel Island contains a high diversity of habitats and climates and conditions vary considerably from one location to another, total reproductive failure of a species in any given year is practically unheard of. Given the relatively small size of the area, this is very unusual in the high Arctic.
Wrangel Island (Russian: о́стров Вра́нгеля, ostrov Vrangelya) is an island in the Arctic Ocean, between the Chukchi Sea and East Siberian Sea. Wrangel Island lies astride the 180° meridian. The International Date Line is displaced eastwards at this latitude to avoid the island as well as the Chukchi Peninsulaon the Russian mainland. The closest land to Wrangel Island is tiny and rockyHerald Island located 60 km (37 mi) to the east.[1]
Wrangel Island is about 125 km (78 mi) wide and 7,600 km2 (2,900 sq mi) in area. It consists of a southern coastal plain that is as wide as 15 km (9.3 mi); a central belt of low-relief mountains; and a northern coastal plain that is as wide as 25 km (16 mi). The east-west trending central mountain belt, the Tsentral'nye Mountain Range, is as much as 40 km (25 mi) wide and 145 km (90 mi) long from coast to coast. Typically, the mountains are a little over 500 m (1,600 ft) above mean sea level. The highest mountain on this island is Sovetskaya Mountain with an elevation of 1,096 m (3,596 ft) above mean sea level. The east-west trending mountain range terminates at sea cliffs at either end of the island.[1]
Wrangel Island belongs administratively to the Chukotka Autonomous Okrug of the Russian Federation. This rocky island has a weather station and two permanent Chukchi fishing settlements on the southern side of the island (Ushakovskoye[1] and Zvyozdny on the shore of Somnitelnaya Bay[2]).
Geology
Wrangel Island consists of folded, faulted, and metamorphosed volcanic, intrusive, andsedimentary rocks ranging in age from Upper Precambrian to Lower Mesozoic. The Precambrian rocks, which are about 2 km (1.2 mi) thick, consist of Upper Proterozoicsericite and chlorite slate and schist that contain minor amounts of metavolcanic rocks,metaconglomerates, and quartzite. These rocks is intruded by metamorphosed gabbro,diabase, and felsic dikes and sills and granite intrusions. Overlying the Precambrian strata are up to 2.25 km (1.4 mi) of Upper Silurian to Lower Carboniferous consisting of interbeddedsandstone, siltstone, slate, argillite, some conglomerate and rare limestone and dolomite. These strata are overlain by up to 2.15 km (1.34 mi) of Carboniferous to Permian limestone, often composed largely of crinoid plates, that is interbedded with slate, argillite and locally minor amounts of thick breccia, sandstone, and chert. The uppermost stratum consists of 0.7 to 1.5 km (0.4 to 0.9 mi) of Triassic clayey quartzose turbidites interbedded with black slate and siltstone.[1]
A thin veneer of Cenozoic gravel, sand, clay and mud underlie the coastal plains of Wrangel Island. Late Neogene clay and gravel, which are only a few tens of meters thick, rest upon the eroded surface of the folded and faulted strata that comprise Wrangel Island. InduratedPliocene mud and gravel, which are only a few meters thick, overlie the Late Neogene sediments. Sandy Pleistocene sediments occur as fluvial sediments along rivers and streams and as a very thin and patchy surficial layer of either colluvium or eluvium.[1]
Fauna and flora
Wrangel Island is a breeding ground for polar bears (having the highest density of dens in the world), seals, walrus, andlemmings. During the summer it is visited by many types ofbirds. Arctic fox also make their home on the island.
Woolly mammoths survived there until 1700 BC, the most recent survival of all known mammoth populations. However, due to limited food supply, they were much smaller in sizethan typical mammoths.[3] Domestic reindeer were introduced in the 1950s and their numbers are managed at around 1,000 in order to reduce their impact on nesting bird grounds. In 1975 musk ox were also introduced. The population has grown from 20 to about 200 animals. Recently, Arctic Wolf have been spotted on the island; wolves have lived on the island in historical times but previous packs were eradicated to reduce predation on reindeer and musk ox.[4]
The flora includes 417 species of plants, double that of any other Arctic tundra territory of comparable size and more than any other Arctic island. For these reasons, the island was proclaimed the northernmost World Heritage Site in 2004.
Climate
Wrangel Island has a severe polar climate. The region is blanketed by dry and cold Arctic air masses for most of the year. Warmer and more humid air can reach the island from the south-east during summer. Dry and heated air from Siberia comes to the island periodically.
Winters are prolonged and are characterized by steady frosty weather and high northerly winds. During this period the temperatures usually stay well below freezing for months. In February and March there are frequent snow-storms with wind speeds of 140 km/h (87 mph) or above.
The short summers are cool but comparatively mild as the polar day generally keeps temperatures above 0 °C (32 °F). Some frosts and snowfalls occur, and fog is common. Warmer and drier weather are experienced in the center of the island because the interior's topography encourages foehn winds.
Average relative humidity is about 82%.
History
Prehistory
This remote Arctic island is believed to be the final place on Earth to support Woolly Mammoths as an isolated population until their extinction 4000 years ago, making them the most recent surviving population known to science.[3][6] A specific variant of the species seems to have survived as a dwarf version of the species originating from Siberia. A combination of late climate change (warming) and the presence of modern humans using advanced hunting and survival skills probably hastened their demise on this frozen isle which until recently was ice bound for most years with infrequent breaks of clear water in some Arctic summers. A mirror development can be found with the Dwarf elephant on Malta, originating from the African species.
Evidence for prehistoric human occupation was uncovered in 1975 at the Chertov Ovrag site.[7] Various stone and ivory tools were found, including a toggling harpoon. Radiocarbon dating shows the human inhabitation roughly coeval with the last mammoths on the island circa 1700 BC, though no direct evidence of mammoth hunting has been found.
A legend prevalent among the Chukchi people of Siberia tells of a chief Krachai (or Krächoj or Krahay), who fled with his people (the Krachaians or Krahays, also identified as the Onkilon or Omoki) across the ice to settle in a northern land.[8][9] Though the story may be mythical, the existence of an island or continent to the north was lent credence by the annual migration of reindeer across the ice, as well as the appearance of slate spear-points washed up on Arctic shores, made in a fashion unknown to the Chukchi. Archaeological, historical, and linguistic evidence has recently been presented that Wrangel Island was a way station on a trade-route linking the Inuit settlement at Point Hope, Alaska with the north Siberian coast, and that the coast may have been colonized in late prehistoric and early historic times by Inuit settlers from North America. The departure of these colonists is suggested to be related to the Krachai legend.[10]
Outside discovery
In 1764 the Cossack Sergeant Stepan Andreyev claimed to have sighted this island. Calling it Tikegen Land, Andreyev found evidence of its inhabitants, the Krahay. Eventually, the island was named after Baron Ferdinand von Wrangel (1797–1870), who, after reading Andreyev's report and hearing Chukchi stories of land at the island's coordinates, set off on an expedition (1820–1824) to discover the island, with no success.
British, American, and Russian expeditions
In 1849, Henry Kellett, captain of HMS Herald, landed on and named Herald Island. He thought he saw another island to the west, which he called Plover Island; thereafter it was indicated on British admiralty charts as Kellett Land.
The first recorded landing on the island was in 1866 by a German whaler, Eduard Dallmann.
In August 1867, Thomas Long, an American whaling captain, "approached it as near as fifteen miles. I have named this northern land Wrangell [sic] Land … as an appropriate tribute to the memory of a man who spent three consecutive years north of latitude 68°, and demonstrated the problem of this open polar sea forty-five years ago, although others of much later date have endeavored to claim the merit of this discovery."
George W. DeLong, commanding USS Jeanette, led an expedition in 1879 attempting to reach the North Pole, expecting to go by the "east side of Kellett land," which he thought extended far into the Arctic. His ship became locked in the polar ice pack and drifted westward, passing within sight of Wrangel before being crushed and sunk in the vicinity of the New Siberian Islands. A landing on Wrangel Island took place on August 12, 1881, by a party from the USRC Corwin, who claimed the island for the United States and named it "New Columbia." The expedition, under the command of Calvin L. Hooper, was seeking the Jeannette and two missingwhalers in addition to conducting general exploration. It included naturalist John Muir, who published the first description of Wrangel Island. The USS Rodgers, also searching for the Jeannette, landed a party on Wrangel Island, also in 1881 but after the Corwin party. They stayed about two weeks and conducted an extensive survey and search.
In 1911, the Russian Arctic Ocean Hydrographic Expedition on icebreakers Vaygach and Taymyr under Boris Vilkitsky, landed on the island.
Stefansson expeditions
In 1914, the survivors of the ill-equipped Canadian Arctic Expedition, organized by Vilhjalmur Stefansson, were marooned there for nine months after their ship, the Karluk, was crushed in the ice pack. The survivors were rescued by the American motorized fishingschooner King & Winge after Captain Robert Bartlett walked across the Chukchi Sea to Siberia to summon help.
In 1921 Wrangel Island would become the stage for one of history's tragedies when Stefansson sent five settlers (the Canadian Allan Crawford, three Americans: Fred Maurer, Lorne Knight and Milton Galle, and Eskimo seamstress and cook Ada Blackjack) in a speculative attempt to claim the island for Canada[17]. The explorers were handpicked by Stefansson based upon their previous experience and academic credentials. Stefansson considered those with advanced knowledge in the fields of geography and science for this expedition. At the time, Stefansson claimed that his purpose was to head off a possible Japanese claim [18]. An attempt to relieve this group in 1922 was thwarted when the schooner Teddy Bear under Captain Joe Bernard became stuck in the ice [19]]. In 1923, the sole survivor of the Wrangel Island expedition, Ada Blackjack, was rescued by a ship that left another party of 13 (American Charles Wells and 12 Inuit). In 1924, the Soviet Union removed the American and the 13 Inuit (one was born on the island) of this settlement. Wells subsequently died of pneumonia in Vladivostok during a diplomatic American-Soviet row about an American boundary marker on the Siberian coast, and so did an Inuit child. The others were deported from Vladivostok to the Chinese border post Suifenhe, but the Chinese government didn't want to accept them as the American consul in Darbin told them the Inuit were not American citizens. Later the American government came up with a statement that the Inuit were 'wards' of the United States, but that there were no funds for returning them. Eventually the American Red Cross came up with $1600 for their return. They subsequently moved through Darwin,Darien, Kobe and Seattle (where another Inuit child drowned during the waiting for the return trip to Alaska) back to Nome. During the Soviet trip the American reindeer owner Carl J. Lomen from Nome had taken over the possessions of Stefansson and had acquired explicit support ("go and hold it") from US Secretary of State Charles Evans Hughes to claim the island for the United States, a goal which the Russian expedition got to hear during their trip. Loman dispatched the MS Herman, commanded by captain Louis L. Lane. Due to unfavorable ice conditions the Herman could not get any further then Herald Island, where the American flag was raised
Soviet rule
In 1926, a team of Soviet explorers, equipped with three years of supplies, landed on Wrangel Island. Clear waters that facilitated the 1926 landing were followed by years of continuous heavy ice surrounding the island. Attempts to reach the island by sea failed and it was feared that the team would not survive their fourth winter.
In 1929, the icebreaker Fyodor Litke was chosen for a rescue operation. It sailed from Sevastopol, commanded by captain Konstantin Dublitsky. On July 4, it reached Vladivostok where all Black Sea sailors were replaced by local crew members. Ten days later Litke sailed north; it passed Bering Strait, and tried to pass De Long Strait and approach the island from south. On August 8 a scout plane reported impassable ice in the strait, and Litke turned north, heading to Herald Island. It failed to escape mounting ice; August 12 the captain shut down the engines to save coal and had to wait two weeks until the ice pressure eased. Making a few hundred meters a day, Litke reached the settlement August 28. On September 5, Litke turned back, taking all the 'islanders' to safety. This operation earned Litke the order of the Red Banner of Labour (January 20, 1930), as well as commemorative badges for the crew.
According to a 1936 article in Time Magazine Wrangel Island became the scene of a bizarre criminal story in the 1930s when it fell under the increasingly arbitrary rule of its appointed governor Konstantin Semenchuk. Semenchuk controlled the local populace and his own staff through open extortion and murder. He forbade the local Eskimos to hunt walrus, which put them in danger of starvation, while collecting food for himself. He was then implicated in the mysterious deaths of some of his opponents, including the local doctor. The subsequent Moscow trial in June 1936 sentenced Semenchuk to death for "banditry" and violation of Soviet law.
A prisoner who later emigrated to Israel, Efim Moshinsky, claims to have seen Raoul Wallenberg there in 1962. However, despite the legends, there never was a Gulag camp on Wrangel.
Post-Soviet era
According to some US individuals, including the group State Department Watch, eight Arctic islands currently controlled by Russia, including Wrangel Island, are claimed by the United States. However, according to the United States Department of State no such claim exists. The USSR/USA Maritime Boundary Treaty, which has yet to be approved by the Russian Duma, does not address the status of these islands.
In 2004 Wrangel Island and neighboring Herald Island, along with their surrounding waters, were added to UNESCO's World Heritage List.
Woolly mammoths, those icons of the ice age that most paleontologists assume died out around 9,500 years ago, survived in miniature form - or what passed for miniature among mammoths - until about 4,000 years ago on an Arctic Ocean island, according to new findings.
Mammoth teeth found in 1991 on Wrangel Island, located 120 miles off the coast of northeast Siberia, range from approximately 7,000 to 4,000 years old, report Andrei V. Sher and Vadim E. Garutt, paleontologists at the Russian Academy of Sciences in Moscow. The relatively small teeth suggest that Wrangel "dwarf mammoths" reached at most 70 percent of the size of their Siberian kin, the researchers say.
"[This is] one of the most extraordinary fossil finds of recent times," writes Adrian M. Lister, a biologist at University College in London, England, in a comment accompanying the new report in the March 25 NATURE.
He estimates that the Wrangel animals stood 6 feet high and weighed 2 tons, compared with 10 1/2 feet and 6 tons for typical European mammoths.
The Wrangel finds may reignite debate over the reasons for the widespread mass extinctions of large mammals between 12,000 and 10,000 years ago, Lister notes. Some researchers contend that the waning ice age produced abrupt environmental changes that doomed many creatures. Others argue that human hunters, at least in North America, rapidly killed off many large-bodied species (SN: 10/31/87, p.284).
"This is a wonderful discovery, however we end up interpreting its significance regarding mass extinctions," remarks Paul S. Martin, an ecologist at the University of Arizona in Tucson, who favors the latter theory,
Sher and Garutt studied 29 adult mammoth cheek teeth found by Sergei L. Vartanyan, a paleontologist at Wrangel Island State Reserve. Five of them are comparable in size to mammoth teeth previously found in Siberia, the researchers contend. Radiocarbon dating places these five specimens at about 20,000 to 13,000 years old.
The remaining 24 teeth are considerably smaller and date from around 7,000 to 4,000 years ago. This confirms similar radiocarbon ages derived last year from more than two dozen mammoth tusk and bone fragments discovered on Wrangel Island, Sher and Garutt assert.
Radiocarbon dating of bone "can be tricky," Martin points out. But fewer soil contaminants seep into bone buried in cold regions, he says. And two independent laboratories produced nearly the same ages for tusk and bone samples, the Russian scientists note.
Siberian mammoths probably reached Wrangel Island during the ice age, when low sea levels created a land bridge to the mainland, Sher and Garutt theorize. By 12,000 years ago, that connection had been submerged.
Unlike nearby islands, Wrangel currently contains vegetation similar to that of ice age grasslands and may have provided a hospitable environment for mammoth survival, the scientists hold. Full-bodied mammoths then evolved into smaller forms on Wrangel, they suggest. Dwarf forms of other large animals existed on late-ice-age islands elsewhere, Sher and Garutt note.
Why the Wrangel mammoths shrank remains unclear, Sher says. Some Siberian mammoths showed body-size decreases by 12,000 years ago, a process that may have accelerated on Wrangel because of the genetic isolation of a small population under nutritional pressures, he suggests.
Scientific reconstruction of plant and animal histories on the island is now under way, Sher points out, as well as an anatomical analysis of large and small Wrangel mammoth teeth.
COPYRIGHT 1993 Science Service, Inc.
Polar Bears: Population on Wrangel Island
The wind howls over Wrangel Island Zapovednik for much of the year. The winters are long and dark and the sun does not appear from November 22 to January 22. Snow blankets the landscape for 240 days of the year. Yet in the spring, tens of thousands of birds arrive to nest on the jagged cliffs, walruses gather on narrow spits to give birth, and female polar bears emerge from their dens with newborn cubs. In the summer, the tundra bursts into life, flowers color the landscape, and rivers run wild in the lush valleys. Wrangel Island and nearby Herald Island are the only land habitats for wildlife in the Chukchi Sea, northwest of the Bering Strait. Russian scientists called for creation of a nature reserve on the islands to protect the delicate Arctic ecosystem from growing human pressures.
Polar bears (Ursus maritimus), Pacific walruses (Odeobenus rosmarus), and snow geese (Anser caerulescens) attracted hunters and settlers to Wrangel in the first half of the 20th century. The decline of these animal populations was one of the reasons for creation of the Wrangel Island Zapovednik. Snow geese originally nested on the Russian mainland from Taimyr to Chukotka, but the large colonies on Wrangel are the last remaining populations in Asia today.
Despite its fierce reputation, the polar bear is a curious and calm creature. The polar bear is protected throughout the Arctic and is listed in the Russian and IUCN Red Books of endangered species. Wrangel and Herald Islands have the largest number of polar bear dens in the Russian Arctic. From 350-500 pregnant bears den on the two islands, or 80% of the breeding population in the Chukotka region. Some areas support 6-12 bears per square kilometer. The majority of the bear population remains at sea throughout the year searching for prey on the ice, returning to land only when the ice floes have melted completely.
The majority of the Pacific Walrus population summers north of the Bering Strait in theChukchi Sea along the north shore of eastern Siberia, around Wrangel Island, in the Beaufort Sea along the north shore of Alaska, and in the waters between those locations. Smaller numbers of males summer in the Gulf of Anadyr on the south shore of Siberia's Chukchi Peninsula and in Bristol Bay off the south shore of southern Alaska west of the Alaska Peninsula. In the spring and fall they congregate throughout the Bering Strait, reaching from the west shores of Alaska to the Gulf of Anadyr. They winter in the Bering Sea along the eastern shore of Siberia south to the northern part of the Kamchatka Peninsula, and along Alaska's southern shore.[3] A 28,000 year old fossil walrus specimen was dredged out of San Francisco Bay, indicating that the Pacific Walrus ranged far south during the last ice age.[24]
The much smaller Atlantic population ranges from the Canadian Arctic, Greenland, Svalbardand the western portion of the Russian Arctic. There are eight presumed sub-populations based largely on geographical distribution and movement data, five to the west of Greenland and three to the east.[25] The Atlantic Walrus once ranged south to Cape Cod and occurred in large numbers in the Gulf of St. Lawrence. In April 2006, the Canadian Species at Risk Act listed the Northwest Atlantic Walrus population (Québec, New Brunswick, Nova Scotia, Newfoundland and Labrador) as being extirpated in Canada.[26]
The isolated Laptev population is confined year-round to the central and western regions of the Laptev Sea, the easternmost regions of theKara Sea, and the westernmost regions of the East Siberian Sea. Current populations are estimated to be between 5,000 and 10,000 individuals.[27]
Their limited diving ability brings them to depend on shallow waters (and appropriate nearby ice coverage) to enable them to reach their preferred benthic prey.
Misconceptions about lemmings go back many centuries. In the 1530s, the geographer Zeigler of Strasbourg proposed the theory that the creatures fell out of the sky during stormy weather (also featured in the folklore of the Inupiat/Yupik at Norton Sound), and then died suddenly when the grass grew in spring.5 This myth was refuted by the natural historian Ole Worm, who accepted that the lemmings could fall out of the sky but that they had been brought over by the wind rather than created by spontaneous generation. It was Worm who first published dissections of a lemming, which showed that they are anatomically similar to most other rodents, and the work of Carl Linnaeus proved that the animals had a natural origin.67
When large numbers of lemmings get on the move, some of them will inevitably drown while crossing rivers and lakes, like this one in Norway.
Lemmings became the subject of a popular myth that they commit mass suicide when they migrate. Driven by strong biological urges, some species of lemmings may migrate in large groups when population density becomes too great. Lemmings can swim and may choose to cross a body of water in search of a new habitat. In such cases, many may drown if the body of water is so wide as to stretch their physical capability to the limit. This fact combined with the unexplained fluctuations in the population of Norwegian lemmings gave rise to the myth. 8
The myth of lemming "mass suicide" is long-standing and has been popularized by a number of factors. In 1955, Disney Studio illustrator Carl Barks drew an Uncle Scrooge adventure comic with the title "The Lemming with the Locket". This comic, which was inspired by a 1954 American Mercury article, showed massive numbers of lemmings jumping over Norwegian cliffs.910 Even more influential was the 1958 Disney film White Wilderness, which won an Academy Award for Documentary Feature, in which staged footage was shown with lemmings jumping into certain death after faked scenes of mass migration.11 A Canadian Broadcasting Corporation documentary, Cruel Camera, found that the lemmings used for White Wilderness were flown from Hudson Bay to Calgary, Alberta, Canada, where they did not jump off the cliff, but were in fact launched off the cliff using a turntable.12
In more recent times, the myth is well-known as the basis for the failed Apple Computer 1985 Super Bowl commercial "Lemmings" and the popular 1991 video game Lemmings, in which the player must stop the lemmings from mindlessly marching over cliffs or into traps. In a 2010 board game by GMT games, "Leaping Lemmings," players must maneuver lemmings across a board while avoiding hazards and successfully launch them off a cliff.
In the arcade mode of the Playstation 2 game Timesplitters: Future Perfect, players can earn the 'Lemming Award' for committing several suicides.
Because of their association with this odd behavior, lemming suicide is a frequently used metaphor in reference to people who go along unquestioningly with popular opinion, with potentially dangerous or fatal consequences. This metaphor is seen many times in popular culture, such as in the video game Lemmings, and in episodes of Red Dwarf and Adult Swim's show Robot Chicken. The Blink 182 song "Lemmings" also uses this metaphor, and the online game Urban Terror, falling to one's death is called doing the lemming thing.
Lesser Snow Geese generally mate for life, and raise an average of three or four young each year. The young migrate with their parents. During the summer, adult geese and the new young birds are all flightless. Scientists from Canada, the United States and Russia all work together to capture some of these birds during this flightless period to mark them so that their migratory paths can be better understood.
These birds fly 4,000 km between Wrangel Island and the Sanctuary. Their migration stops between nesting and wintering grounds include the Russian mainland, St.Lawrence Island (Bering Sea), the Yukon-Kuskokwin delta (western Alaska), Cooke Inlet (southern Alaska), and the mouth of the Stikine River in northern BC. Some marked individuals have made non-stop flights between Alaska and the Sanctuary (2500 km) in less than 36 hours.
Our Snow Geese start arriving at the Sanctuary in early October and are often referred to as the "Fraser-Skagit” flock or subpopulation, as they move back and forth between the estuaries of the Fraser and Skagit Rivers. The Sanctuary is in the center of the Fraser River estuary. The Skagit River estuary is just south of the Canada/United States border in the State of Washington, and it provides the birds with similar habitats to what they find in the Fraser River estuary- flat farmland next to extensive intertidal marshes. Each area traditionally supports approximately 50% of the flock in the fall, but nearly all of the flock concentrates in the Skagit estuary from late December to February. Birds return to the Fraser estuary in spring, and depart in April for their northward migration to Wrangel Island. Nesting pairs are on their nests and incubating eggs most of June, and the resulting young are ready to fly by late August.
During their stay here, favourite natural foods for these birds are the intertidal marsh plants of the estuary. Marsh plants such as bulrush (Scirpus americanus) store starch reserves in their roots and rhizomes. The geese dig up these food sources using their strong bills. The soils in the Delta area are rich in iron compounds, and stain the head feathers of the geese orange when they have been digging in the marsh. In the spring, the green growth of pastures and marsh plants such as sedge (Carex lyngbeyi) are popular foods.
Agricultural crops are also eaten, although most are harvested by farmers before the snow geese arrive. Leftover potatoes often remain in the fields, and the geese dig these up. Local farmers all participate in a program called “Greenfields” which coordinates the fall planting of green growing grass cover for these geese, other wildlife and soil enrichment through the Delta Farmland and Wildlife Trust.
The snow geese provide spectacular wildlife viewing for our visitors. They form very large dense flocks of up to 20,000 birds which feed, rest and fly over the Sanctuary, neighbouring farmland and nearby Fraser marshes every day. They are restless and constantly moving when Bald Eagles, people and dogs are nearby. Within the flocks, visitors can often identify family groups. The young born that year are fully grown before they migrate to this area, but their first set of adult feathers is grey, not white. Small groups containing two white birds and several darker birds are likely family groups. The snow geese regularly sleep on the water in large dense flocks, sometimes out in the marshes of the estuary, and sometimes in the quiet river channels around the Sanctuary.
The gray whale is a baleen whale or filter feeder and have 2-4 throat grooves, about 5 feet (1.4 m) long each. These grooves allow their throat to expand during the huge intake of water during filter feeding. The baleen plates in the gray whale's jaws have about 160 pairs of short, smooth baleen plates. The largest plates are about 15 inches long and 10 inches wide. The baleen bristles are thicker than those of the other baleen whales and are gray with yellowish bristles. The huge, narrow, pink tongue of the gray whale is used to dislodge the food from the baleen, and weighs about 1-1.5 tons (0.9-1.36 tonnes).
The gray whale's skin is usually gray with some blotchy white spots and has many parasites, including hundreds of pounds of barnacles and whale lice. There are little or no parasites on its right side because of the way it scrapes along the ocean bottom to feed.
They have a layer of blubber up to 10 inches (25 cm) thick and there are hairy bristles (vibrassae) on the gray whale's snout and the front of the head. These are used as tactile sensors, like cat's whiskers.
The gray whale has two broad flippers, no dorsal fin, and a series of small ridges along the its back near the flukes (tail).
Bibliography.
· www.wikipedia.org
· http://whc.unesco.org/en/list/1023/
· www.monolith.com
· www.encyclopedia.com/topic/Wrangel_Island.aspx
· Article: 'Dwarf' mammoths outlived last ice age'
from: Science News
March 27, 1993
Bower, Bruce
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