Bird Families

Thick Billed Murre - Facts | Adaptation | Egg | Dive | Habitat

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The thick billed murre is a huge, mighty, deep swimming and diving bird breed in the cool seawater. Very similar to Common Moore. The two are found together in several places, even nesting on the same end of the rocky northern islands, but there are centers of abundance on the thick-extinct north. Despite the recent collapse, the population of the Eastern Canadian Arctic is undoubtedly rising to a few million.

Thick billed murre facts

The thick-billed murre or Brannich's guillemet (urea Lomvia) is a bird of the Auke family (Alcidia). The thick billed murre was named after Danish zoologist Morten Thren Brannich. The deeply dark North Pacific subspecies of the urea Lomvia aura is also called the Moor of Palace after its descriptor.

The name of the genus is a watercolor described by the ancient Greek Ourea, Athenaeus. The species word Lomvia is a Swedish word for auk or diver. The English “Guillemot” is derived from the French Guillemot, probably from Gilliam, “William”. “Murray” is of uncertain origin, but may mimic the call of General Guillemot.

Moores have the highest flight costs for any animal body size.

Description

The head color of the thick billed murre is uniform throughout the bridging plumage in all of Bridnich's Gillette

With the extinction of the Great Auke in the mid-nineteenth century, the murderers are the largest surviving member of the Alcidi. The thick billed murre and the closely related common guillimut (or common vacuum, ULZ) are the same size, but the thick-billed still bind both the average and maximum size of the other species.

The thick-billed twist measures 40-48 cm (16 in19 in) in total length, extends 64-81 cm (25-32 in) across the wings and weighs 736-1,481 g (26.0-52.2 oz). The Pacific nation (US) is larger than the Atlantic, especially with bill levels.

The adult birds are black with white underparts on the head, neck, back, and wings. The bill is long and pointed. They have a small round black tail. The lower face turns white in winter. This species produces a variety of rigid cackling calls in breeding colonies but remains silent in the ocean.

They differ from the simple peacocks of their dense, short bills, striped in white; The “bridesmaid” variant consists of a white eye stripe, or a white bill-stripe, or both, but not both, in a twist unknown in Lomvia, USA; This could be the displacement of this character, enabling individual birds to detect conspecifics at a distant location in densely packed breeding colonies because braided morphs are by far the most common in the North Atlantic colonies where both species of gillimut species are bred.

In winter, thicker bills have less white at the mouth. They seem shorter than the normal flight trim. First-year birds have smaller bills than older ones, and the white line of the bill is often blurred, making it an incredible way for the bill to detect them at this age. The pattern of the head is one of the best ways to distinguish first-year birds from a common killer.

Distribution

The dense-build spaces are distributed in the polar and sub-polar regions of the Northern Hemisphere where there are four subspecies; One life in the North American Atlantic and Arctic Oceans (U. L. Lomvia), the other resides in the Pacific coast of North America (U. L. Ara), and two others live in the Russian Arctic (Euleniore and U. Checkeri).

Habitat

Thick-billed killers spend less than 8 ° C all their life in seawater, except during the breeding season where they form dense colonies in the cliffs. Oceans colonize colonies at the climax of the ocean. The choice of very cool seawater in the Arctic; When not nesting, it is often far from the ground over deep water. The pack can be attached to the edge or opening of the ice. Nestled on rocky shores or islands with steep cliffs.

Breeding

Thick-billed killers form large breeding colonies, sometimes composed of over one million breeding birds facing the water at narrow ends and steep cliffs. They have the smallest area of ​​any bird, which requires less than one square foot per individual. A breeding pair lays one egg per year. Despite this, they are one of the most abundant marine birds in the Northern Hemisphere.

Adults display communalism early in the breeding season during their reproductive cycle. They do not nest, but lay eggs directly on empty stones. Both parents are involved in hatching and raising the baby. Due to the large amount of energy needed to get on the flight, adults can provide their chickens with only one meal at a time.

Goats spend 18 to 25 days up the mountain before heading out to sea. Once ready to go out, the youngsters will wait for the nightfall and jump to the water. One of the parents immediately jumped in and walked within a centimeter of freshness. At sea, men and chick live together for about 8 weeks during which adults provide food for the children.

The survival rate of the young thick billed murre is not based on the individual population of the colony, but on the age of the breeders in the colony [the offspring of the inexperienced couple grows more slowly than the experienced breeders, probably because they do not receive as much food from their parents.

Also, the hatch rate is lower among the joints that have at least one young breeding bird. Older and more experienced adults receive better nesting sites in the center of the colony, while inexperienced individuals are placed at the margin of their margins where their young adults are more likely to be victims.

Migratory patterns

In winter, thick billed murre moves to the South Atlantic and the northern part of the Pacific but only to be kept in ice-free waters.

Flight and feeding features

The thick-billed twisted flight is strong and straight and their short wings beat their wings quickly. Like other birds, these birds dip into the wings and use wings to swim. They are skilled divers, reaching a depth of 150 meters and diving for four minutes at a time; Generally, however, the birds either make shallow short dives or sink below 21-40 meters for a long period of time. When hunting, the diving trajectory is analogous to a flat 'U'.

The bird will make the long journey to the desired eating place; They usually travel more than 100km when they travel dozens of kilometers from their home. The result of their short wings, for their body size, powerful and direct aircraft of the Moors, the most expensive form of sustainable locomotion of any animal

The depth and duration of diving that are regularly acquired by these birds indicate that they and similar auks, some mechanisms for diving and some to continue to avoid lung collapse are still unknown - it is imperative that auks temporarily absorb the excess gases in the vascular formation of their bones. From there it is gradually released from temporary storage in a controlled process of erosion.

Egg

Thick billed murre lay one egg. Very variable, usually white, tan, blue or green with brown and black markings. Incubation is by both sexes, 30-35 days. A parent is almost always in the nesting cycle. Young: Both parents feed. Adults often walk many miles to the colony. Youth is able to leave home at 15-30 days; Comes down to the sea with an adult male. Young men are looked after for several weeks after leaving home.

Juvenile

Both parents feed the thick billed murre. Adults often walk many miles to the colony. Youth is able to leave home at 15-30 days; Comes down to the sea with an adult male. Young men are looked after for several weeks after leaving home.

Status and Conservation

Although their range has declined in most places, the thick-billed build is not a species of concern as the total population is estimated to be between 15 and 20 million people worldwide.

The population is still a few million, but in recent decades a 20% -50% reduction in several large colonies is a cause for concern. Eggs and adults are harvested for food by locals in some Arctic regions. The major threats to survival are the mass casualties and pollution in fishing nets, the risk of oil spills and the effects of climate change.

The threat of egg collection and adult birds are threatened in Greenland, where the population declined between the 3 and the 7. In the Barents Sea region, the species has declined locally due to the influence associated with polar centers in Russia.

Fisheries may also be a threat, but the effect of over-phishing is not as severe as in ordinary burials due to being able to use alternative food sources due to fattened bills. Pollution from sea oil faces another major threat. Moores are among the most sensitive marine to oil pollution. Accidental mortality associated with fishing gear is also an important factor in population decline.

Thick-billed murders have been associated with sea-ice all year round. As a result, some scientists believe that climate change could be a threat to this Arctic-bred species. However, the species appears to be adaptable. As eastern ice turned into ice breaks, populations on the southern end of their range shifted from feeding ice-related Arctic cod to hot-water capelins.

The dates for the laying of eggs progressed as the ice disappeared. The growth of children is slow during the years when ice breaks are sooner than when laid by eggs by Moore. In extremely hot years, mosquitoes and heats kill some breeders.

Diet

Thick billed murre eats fish. Diet is essentially fish in summer (and young people are almost completely fed on fish); Winter may include more crustaceans. Fish in the diet include cod, herring, capelin, sand lance, scalpin and many more. The crustaceans eat include shrimp, amphipods, mysids, copepods. Some marine worms, also eat squid.

Of birds

Probably over 3 years old at first breeding. Home to colonies, some are very large. Some joints may have formed before coming to the colony. At the nest site, members of the pair hang on to each other's bills; The stones can be picked up and presented to each other. The nest site is on the cliffside; Common can use a narrower and shorter tail than Moore. There is no nest, the eggs lie on bare stones.

Watch the video: Common Murres at Farallon NWR (June 2021).

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