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51-694: Foxe Basin is a shallow oceanic basin north of Hudson Bay , in Nunavut , Canada, located between Baffin Island and the Melville Peninsula . For most of the year, it is blocked by sea ice ( fast ice ) and drift ice made up of multiple ice floes . The nutrient-rich cold waters found in the basin are known to be especially favourable to phytoplankton and the numerous islands within it are important bird habitats , including Sabine's gulls and many types of shorebirds . Bowhead whales migrate to

102-469: A global ocean model. These trajectories are of particles that move only on the surface of the ocean. The model outcome gives the probability of a particle at a certain grid point to end up somewhere else on the ocean's surface. With the model outcome a matrix can be created from which the Eigenvectors and Eigenvalues are taken. These Eigenvectors show regions of attraction, aka regions where things on

153-411: A mile away. White- and blue-morph birds interbreed and the offspring may be of either morph. These two colors of geese were once thought to be separate species; since they interbreed and are found together throughout their ranges, they are now considered two color phases of the same species. The color phases are genetically controlled. The dark phase results from a single dominant gene and the white phase

204-504: A particle on the ocean surface in a certain region is more likely to stay in the same region than to pass over to a different one. Depending on the chemical composition and the physical state, the Earth can be divided into three major components:  the mantle , the core , and the crust . The crust is referred to as the outside layer of the Earth. It is made of solid rock, mostly basalt and granite . The crust that lies below sea level

255-605: Is a rare vagrant to Europe , but escapes from collections have occurred, and it is an occasional feral breeder. Snow geese are visitors to the British Isles where they are seen regularly among flocks of brant , barnacle goose , and greater white-fronted goose . There is also a feral population in Scotland from which many vagrant birds in Britain seem to derive. Around 2015, a small group of 3-5 snow geese landed on

306-585: Is a shallow depression lined with plant material and may be reused from year to year. After the female lays the first of three to five eggs, she lines the nest with down. The female incubates for 22 to 25 days, and the young leave the nest within a few hours of hatching. The young feed themselves, but are protected by both parents. After 42 to 50 days they can fly, but they remain with their family until they are two to three years old. Where snow geese and Ross's geese breed together, as at La Pérouse, they hybridize at times, and hybrids are fertile. Rare hybrids with

357-580: Is a species of goose native to North America. Both white and dark morphs exist, the latter often known as blue goose . Its name derives from the typically white plumage . The species was previously placed in the genus Chen , but is now typically included in the "gray goose" genus Anser . Snow geese breed north of the timberline in Greenland , Canada , Alaska , and the northeastern tip of Siberia , and spend winters in warm parts of North America from southwestern British Columbia through parts of

408-555: Is affected not only by the volume of the ocean basin, but also by the volume of water in them. Factors that influence the volume of the ocean basins are: The Atlantic Ocean and the Arctic Ocean are good examples of active, growing oceanic basins, whereas the Mediterranean Sea is shrinking. The Pacific Ocean is also an active, shrinking oceanic basin, even though it has both spreading ridge and oceanic trenches. Perhaps

459-429: Is drab or slate-gray with little to no white on the head, neck, or belly. Both snow and blue phases have rose-red feet and legs, and pink bills with black tomia ("cutting edges"), giving them a black "grin patch". The colors are not as bright on the feet, legs, and bill of immature birds. The head can be stained rusty-brown from minerals in the soil where they feed. They are very vocal and can often be heard from more than

510-454: Is from the Latin anser , "goose", and caerulescens , "bluish", derived from caeruleus , "dark blue". The snow goose is the sister species to Ross's goose ( Anser rossii ). Two subspecies are recognised: The greater snow goose is distinguished from the nominate form by being slightly larger. It nests farther north and east. The lesser snow goose can be found in two color phases ,

561-460: Is homozygous recessive. When choosing a mate, young birds will most often select a mate that resembles their parents' coloring. If the birds were hatched into a mixed pair, they will mate with either color phase. The species is divided into two subspecies on the basis of size and geography. Size overlap has caused some to question the division. The smaller subspecies, the lesser snow goose ( C. c. caerulescens ), lives from central northern Canada to

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612-532: Is known as the oceanic crust , while on land it is known as the continental crust . The former is thinner and is composed of relatively dense basalt, while the latter is less dense and mainly composed of granite. The lithosphere is composed of the crust (oceanic and continental) and the uppermost part of the mantle. The lithosphere is broken into sections called plates . Tectonic plates move very slowly (5 to 10 cm (2 to 4 inches) per year) relative to each other and interact along their boundaries. This movement

663-604: Is responsible for most of the Earth's seismic and volcanic activity. Depending on how the plates interact with each other, there are three types of boundaries. The Earth's deepest trench is the Mariana Trench which extends for about 2500 km (1600 miles) across the seabed. It is near the Mariana Islands , a volcanic archipelago in the West Pacific. Its deepest point is 10994 m (nearly 7 miles) below

714-424: Is rocky and rugged in the southern half of the region, and generally low-lying in the north. High cliffs are found across the southern portion of the region, where most of the seabirds nest. Coastal marshes and tidal flats up to 6.5 km (4.0 mi) in width are found in the vast lowland section of eastern Foxe Basin, as well as in the bays of Southampton Island . This is one of the little-known areas of

765-603: Is the Southern Ocean (20 million km / 7 million mi ). All ocean basins collectively cover 71% of the Earth's surface, and together they contain almost 97% of all water on the planet. They have an average depth of almost 4 km (about 2.5 miles). "Limits of Oceans and Seas" , published by the International Hydrographic Office in 1953, is a document that defined the ocean's basins as they are largely known today. The main ocean basins are

816-693: The Atlantic coastal plain . Traditionally, lesser snow geese wintered in coastal marsh areas where they used their short but strong bills to dig up the roots of marsh grasses for food. However, they have also since shifted inland towards agricultural areas, likely the cause behind the unsustainable population increase in the 20th century. This shift may help to contribute to increased goose survival rates, leading to overgrazing on tundra breeding grounds. In March 2015, 2,000 snow geese were killed in northern Idaho from an avian cholera epidemic while flying their spring migration to northern Canada . The snow goose

867-559: The Bering Straits area. The lesser snow goose stands 64 to 79 cm (25 to 31 in) tall and weighs 2.05 to 2.7 kg (4.5 to 6.0 lb). The larger subspecies, the greater snow goose ( C. c. atlanticus ), nests in northeastern Canada. It averages about 3.2 kg (7.1 lb) and 79 cm (31 in), but can weigh up to 4.5 kg (9.9 lb). The wingspan for both subspecies ranges from 135 to 165 cm (53 to 65 in). Long-term pair bonds are usually formed in

918-753: The bowhead whale , beluga whale and narwhal . Both bowhead whales and belugas winter in the waters of northeastern Hudson Bay . Bowheads were the only known baleen whales to occur in the Hudson Bay, but recently some other species of whale, such as humpback and minke , are confirmed to migrate into the waters as well. The region is the main North American stronghold of the Sabine's gull , with some 10,000 pairs nesting here. Moderate numbers of black guillemots , Arctic terns and glaucous , herring and ivory gulls also breed here. The Great Plain of

969-483: The greater white-fronted goose , Canada goose , and cackling goose have been observed. Snow geese breed from late May to mid-August, but they leave their nesting areas and spend more than half the year on their migration to-and-from warmer wintering areas. During spring migration (the reverse migration), large flocks of snow geese fly very high and migrate in large numbers along narrow corridors, more than 3,000 mi (4,800 km) from traditional wintering areas to

1020-804: The Atlantic and Arctic basins. The Atlantic Basin began to form around 180 million years ago, when the continent Laurasia (North America and Eurasia ) started to drift away from Africa and South America. The Pacific plate grew, and subduction led to a shrinking of its bordering plates. The Pacific plate continues to move northward. Around 130 million years ago the South Atlantic started to form, as South America and Africa started to separate. At around this time India and Madagascar rifted northwards, away from Australia and Antarctica, creating seafloor around Western Australia and East Antarctica. When Madagascar and India separated between 90 and 80 million years ago,

1071-542: The Canadian Arctic , though it is proving to be biologically rich and diverse. The numerous polynyas in northern Foxe Basin support high densities of bearded seals and the largest walrus herd in Canada (over 6,000 individuals). Ringed seal and polar bear are common, with north Southampton Island as one of the highest-density polar bear denning areas in Canada. This area is also an important summering area for

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1122-457: The Hudson Bay coastline. The cause of this overpopulation may be the heavy conversion of land from forest and prairie to agricultural usage in the 20th century. Since the late 1990s, efforts have been underway in the U.S. and Canada to reduce the North American population of lesser snow and Ross's geese to sustainable levels due to the documented destruction of tundra habitat in Hudson Bay and other nesting areas. The Light Goose Conservation Order

1173-459: The Koukdjuak on Baffin Island is the world's largest goose nesting colony, with upwards of 1.5 million birds, 75 per cent of which are lesser snow geese and the remainder Canada and brant geese. Shorebirds and ducks are also abundant. Several hundred thousand thick-billed murres breed on the cliffs of Digges Sound and Coats Island to the south. This region is not yet represented in

1224-617: The Mariana Islands. It is located far away from oceanic spreading centers, where oceanic crust is constantly created or destroyed. The oldest crust is estimated to be only around 200 million years old, compared to the age of Earth which is 4.6 billion years. 200 million years ago nearly all land mass was one large continent called Pangea , which started to split up. During the splitting process of Pangea, some ocean basins shrunk, such as the Pacific, while others were created, such as

1275-609: The Swedish naturalist Carl Linnaeus updated his Systema Naturae for the tenth edition , he placed the snow goose with the ducks and geese in the genus Anas . Linnaeus included a brief description, coined the binomial name Anas caerulescens and cited Edwards' work. The snow goose is now placed in the genus Anser that was introduced by the French zoologist Mathurin Jacques Brisson in 1760. The scientific name

1326-600: The United States to Mexico . In 1750 the English naturalist George Edwards included an illustration and a description of the snow goose in the third volume of his A Natural History of Uncommon Birds . He used the English name "The blue-winged goose". Edwards based his hand-coloured etching on a preserved specimen that had been brought to London from the Hudson Bay area of Canada by James Isham . When in 1758

1377-672: The best example of an inactive oceanic basin is the Gulf of Mexico, which formed in Jurassic times and has been doing nothing but collecting sediments since then. The Aleutian Basin is another example of a relatively inactive oceanic basin. The Japan Basin in the Sea of Japan which formed in the Miocene , is still tectonically active although recent changes have been relatively mild. Snow goose The snow goose ( Anser caerulescens )

1428-518: The high sediment content of the water makes the sea ice of Foxe Basin dark and rough, easily distinguishable from other ice in the Canadian Arctic . Foxe Basin is connected to the Gulf of Boothia via the narrow Fury and Hecla Strait , and to Hudson Bay and Hudson Strait via the wide Foxe Channel . It is also connected to Naujaat and Roes Welcome Sound via Frozen Strait . The terrain

1479-572: The individual ocean basins has fluctuated in the past due to, amongst other, tectonic plate movements. Therefore, an oceanic basin can be actively changing size and/or depth or can be relatively inactive. The elements of an active and growing oceanic basin include an elevated mid-ocean ridge , flanking abyssal hills leading down to abyssal plains and an oceanic trench . Changes in biodiversity, floodings and other climate variations are linked to sea-level, and are reconstructed with different models and observations (e.g., age of oceanic crust). Sea level

1530-539: The lesser snow goose exceeds 5 million birds, an increase of more than 300% since the mid-1970s. The population is increasing at a rate of more than five percent per year. Non-breeding geese (juveniles or adults that fail to nest successfully) are not included in this estimate, so the total number of geese is likely higher. Lesser snow goose population indices are the highest they have been since population records have been kept, and evidence suggests that large breeding populations are spreading to previously untouched sections of

1581-506: The line between the North and South Atlantic is set at the equator . The Antarctic or Southern Ocean, which reaches from 60° south to Antarctica had been omitted until 2000, but is now also recognized by the International Hydrographic Office. Nevertheless, and since ocean basins are interconnected, many oceanographers prefer to refer to one single ocean basin instead of multiple ones.   Older references (e.g., Littlehales 1930) consider

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1632-636: The national marine conservation areas system. Studies to identify preliminary representative marine areas have yet to be undertaken. Oceanic basin Most commonly the ocean is divided into basins following the continents distribution : the North and South Atlantic (together approximately 75 million km / 29 million mi ), North and South Pacific (together approximately 155 million km / 59 million mi ), Indian Ocean (68 million km / 26 million mi ) and Arctic Ocean (14 million km / 5.4 million mi ). Also recognized

1683-446: The normal white-colored animals and a dark gray-colored "blue" phase. The greater snow goose is rarely seen in a blue phase. The snow goose has two color plumage morphs , white (snow) or gray/blue (blue), thus the common description as "snows" and "blues". White-morph birds are white except for black wing tips, but blue-morph geese have bluish-gray plumage replacing the white except on the head, neck and tail tip. The immature blue phase

1734-491: The north shore of O'ahu . They were seen and photographed several times over the course of 3-4 months. In Central America , vagrants are frequently encountered during winter. Outside of the nesting season, they usually feed in flocks. In winter, snow geese feed on left-over grain in fields. They migrate in large flocks, often visiting traditional stopover habitats in spectacular numbers. Snow geese frequently travel and feed alongside greater white-fronted geese ; in contrast,

1785-445: The northern part of the basin each summer. The basin takes its name from the English explorer Luke Foxe who entered the lower part in 1631. Foxe Basin is a broad, predominantly shallow depression, generally less than 100 m (330 ft) in depth, while to the south, depths of up to 400 m (1,300 ft) occur. The tidal range decreases from 5 m (16 ft) in the southeast to less than 1 m (3 ft 3 in) in

1836-436: The northwest. During much of the year, landfast ice dominates in the north, while pack ice prevails towards the south. Foxe Basin itself is rarely ice-free until September, open pack ice being common throughout the summer. Vigorous tidal currents and strong winds keep the ice pack in constant motion and contribute to the numerous polynyas and shore leads which are found throughout the region. This same motion, combined with

1887-406: The ocean is very slow compared to horizonal flow and observing the deep ocean is difficult. Defining the ocean basins based on connectivity of the entire ocean (depth and width) is therefore not possible. Froyland et al. (2014) defined ocean basins based on surface connectivity. This is achieved by creating a Markov Chain model of the surface ocean dynamics using short term time trajectory data from

1938-440: The oceanic basins to be the complement to the continents , with erosion dominating the latter, and the sediments so derived ending up in the ocean basins. This vision is supported by the fact that oceans lie lower than continents, so the former serve as sedimentary basins that collect sediment eroded from the continents, known as clastic sediments, as well as precipitation sediments. Ocean basins also serve as repositories for

1989-827: The ones named in the previous section. These main basins are divided into smaller parts. Some examples are: the Baltic Sea (with three subdivisions), the North Sea , the Greenland Sea , the Norwegian Sea , the Laptev Sea , the Gulf of Mexico , the South China Sea , and many more. The limits were set for convenience of compiling sailing directions but had no geographical or physical ground and to this day have no political significance. For instance,

2040-514: The owls, since they are predatory, were capable of keeping competing predators away from the nests. A similar association as with the owls has been noted between geese and rough-legged hawks . Additional predators at the nest have reportedly included wolves , coyotes and all three North American bear species. Few predators regularly prey on snow geese outside of the nesting season, but bald eagles (as well as possibly golden eagles ) will readily attack wintering geese. The breeding population of

2091-474: The recommendation on ways to combat the growing population and the damage that the snow geese were creating in the arctic breeding grounds. The committee recommended relaxing hunting restrictions and giving hunters a better opportunity to harvest more snow geese on their way back to the breeding grounds in the spring. The suggested restrictions were to allow the use of electronic callers, unplugged shotguns, extended shooting hours, and no bag limits. Two years after

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2142-471: The same habitat. Major nest predators include Arctic foxes and skuas . The biggest threat occurs during the first couple of weeks after the eggs are laid and then after hatching. The eggs and young chicks are vulnerable to these predators, but adults are generally safe. They have been seen nesting near snowy owl nests, which is likely a solution to predation. Their nesting success was much lower when snowy owls were absent, leading scientists to believe that

2193-407: The second year, although breeding does not usually start until the third year. Females are strongly philopatric, meaning they will return to the place they hatched to breed. Snow geese often nest in colonies. Nesting usually begins at the end of May or during the first few days of June, depending on snow conditions. The female selects a nest site and builds the nest on an area of high ground. The nest

2244-455: The skeletons of carbonate - and silica -secreting organisms such as coral reefs , diatoms , radiolarians , and foraminifera . More modern sources (e.g., Floyd 1991) regard the ocean basins more as basaltic plains, than as sedimentary depositories, since most sedimentation occurs on the continental shelves and not in the geologically defined ocean basins. The flow in the ocean is not uniform but varies with depth. Vertical circulation in

2295-673: The spreading ridges in the Indian Ocean were reorganized. The northernmost part of the Atlantic Ocean was also formed at this time when Europe and Greenland separated. About 60 million years ago a new rift and oceanic ridge formed between Greenland and Europe, separating them and initiating the formation of oceanic crust in the Norwegian Sea and the Eurasian Basin in the eastern Arctic Ocean. The area occupied by

2346-434: The surface of the ocean (plastic, biomass, water etc.) become trapped. One of these regions is for example the Atlantic garbage patch . With this approach the five main ocean basins are still the North and South Atlantic, North and South Pacific and the Arctic Ocean, but with different boundaries between the basins. These boundaries show the lines of very little surface connectivity between the different regions which means that

2397-492: The surface of the sea. The Earth's longest trench runs alongside the coast of Peru and Chile, reaching a depth of 8065 m (26460 feet) and extending for approximately 5900 km (3700 miles). It occurs where the oceanic Nazca plate slides under the continental South American plate and is associated with the upthrust and volcanic activity of the Andes. The oldest oceanic crust is in the far western equatorial Pacific, east of

2448-553: The tundra. The lesser snow goose travels through the Central Flyway , Mississippi Flyway , and Pacific Flyway across prairie and rich farmland to their wintering grounds on grassland and agricultural fields across the United States and Mexico, especially the Gulf coastal plain . The larger and less numerous greater snow goose travels through the Atlantic Flyway and winters on a relatively more restricted range on

2499-570: The two tend to avoid travelling and feeding alongside Canada geese , which are often heavier birds. The population of greater snow geese was in decline at the beginning of the 20th century, but has now recovered to sustainable levels. Snow geese in North America have increased to the point where the tundra breeding areas in the Arctic and the saltmarsh wintering grounds are both becoming severely degraded, and this affects other species using

2550-492: Was also causing critical damage to other varieties of waterfowl species and other wildlife that uses the arctic and sub-arctic grounds for home habitat. The increase in population in substantial amounts raised concern to then DU chief biologist Dr. Bruce Batt who was part of a committee that put together various data and submitted it to the U.S. Fish and Wildlife Service and the Canadian Wildlife Service with

2601-441: Was established in 1997 and federally mandated in 1999. Increasing hunter bag limits, extending the length of hunting seasons, and adding new hunting methods have all been successfully implemented, but have not reduced the overall population of snow geese in North America. The late 1990s was when the mid-continent population of snow geese was recognized as causing significant damage to the arctic and sub-arctic breeding grounds which

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