Brachyramphus
Marmelalk
Brachyramphus is a genus of the family of Auks, among the three extant species. By 1996, only two extant species have been recorded to the genus. The now recognized as an independent species Kamtschatkamarmelalk was up to this time as a subspecies of Marmelalks. Findings based on mtDNA and allozymes showed, however, that the Marmelalk is more closely related to Kurzschnabelalk and Kamtschatkamarmelalk is a sister species of the two. All three species, however, are very closely related, the split into different types occurred within the last two to three million years.
All three extant species exhibit an unusual behavior for Auks. They nest singly in the rule and its Niststandorte often find themselves far away from the coast.
Appearance
All three species reach a body length of about 25 centimeters. They belong to the very small Alkenvögeln. From other Alkenvögeln they are distinguished by their small body size, the relatively slender physique and the relatively long, pointed wings. They have very short legs that target very far back on the body. Because of this, Kurzschnabelalke move very awkwardly continued on land. Floating animals carry their head obliquely upwards, the tail jutting out of the water and is also directed upwards.
The plumage of the three species resembles very strongly. In breeding plumage the entire body plumage is mottled with irregular dark chocolate brown on a white ground. In Plain dress the plumage is entirely black and white, so that it resembles the plumage of a guillemot.
The beak is for all three types of black, short and pointed. The largest beak length has the Kamtschatkamarmelalk. The Kurzschnabelalk has the shortest beak of the three species. He is a total of slightly more curved and looks even smaller than it actually is by the springs forwardly.
Distribution area
All three extant species are limited to the North Pacific.
The North American Marmelalke breed on the west coast of North America from southern California through Oregon, Washington, British Columbia and the West Coast of Vancouver Iceland to southeastern Alaska, and also in the western Aleutian Islands. However, the prerequisite is always an extensive stock of old trees, which is why the stocks in California, Oregon and Washington are small and fragmented, because these conditions are no longer met.
The North American distribution area of Kurzschnabelalks ranges from the LeConte Bay in Southeast Alaska on Prince William Sound, the Kenai Peninsula, Kodiak Island and Afognak isolated in Iceland to the Bering Strait and the Aleutian Islands. Kurzschnabelalke that breed on the coast of the Bering Strait, must pull southward, as these waters freeze after the breeding season. Otherwise, however, few southward train movements of North American birds can be observed. Individual vagrants were observed to the south of British Columbia and to the coasts of the U.S. states of Washington and California.
In Siberia the Kurzschnabelalk occurs mainly in the northern part of the Okhotsk Sea. Breeding birds but are also found on the coasts of the Chukchi Peninsula and on Karaginski. However Kurzschnabelalken occasionally be observed, for example, on the Kuril Islands and Hokkaido also significantly further south. Also significantly further north Kurzschnabelalken were observed. It is possible that the type of hatches on Wrangel.
The breeding range of the Kamtschatkamarmelalkes extending along the shores of the Sea of Okhotsk, the Kamchatka Peninsula and Sakhalin to Hokkaido, where this species breeds sporadically. During the winter months the northern breeding birds move south to avoid the ice.
Similar to the Kurzschanbelalk Kamtschatkamarmelalke are frequently observed well outside of their range. Secured observations are available for both species in North America, among others, from Florida, Pennsylvania, New Jersey, New York, Massachusetts and Newfoundland. When the found in a fishing net in Lake Zurich in December 1997 individual is believed to be an Kamtschatkamarmelalk. A second living individual of Kamtschatkamarmelalkes appeared at the beginning of November 2006 in Devon, England, and was observed for several days.
Reproduction
None of the three species of the genus Brachyramphus breeds in colonies, which is a rather unusual breeding behavior within the Auks. Your Niststandorte found some of them very far inland. The Kurzschnabelalk is a ground-nesting birds, the preferred invests its nests on mountain tops above the timber line. This breeding behavior was already known at the beginning of the 20th century. Persons of the indigenous population from the breeding region had reported variously compared to ornithologists about this breeding behavior, however, were initially encountered from skepticism. All three species lay only one egg, which is incubated by both parents birds.
The breeding behavior of Kamchatka and Marmelalk became known only during the second half of the 20th century. Both species preferred breed on old mighty trees. Their nest is located in the upper area of the respective Nistbaumes on strong branches, and is neither the ground nor the air out to discover.
Particularly well studied is the breeding behavior of the Marmelalkes, the bird became a symbol of the efforts to preserve unsprünglicher forests on the coasts of the United States in North America. The breeding range of this species is usually removed 16.8 km from the coast, on average. Extreme Niststandorte can be found up to 40 kilometers away. The typical Niststandort found on old trees, as are at least 200 years. Typical of the forests in which nest Marmelalken, is a small understory under the tall trees, but a pronounced moss and epiphyte. The top height of the trees is on average approximately 64 meters in height, the size of the forests in which brood Marmelalke, is 206 hectares on average. The nest is located in the upper area of the Nistbaumes about a meter away from the tree trunk on a strong branch that offers a Nistplattform of about twenty by thirty inches square. The nest is lined with lichens and moss and is due to over hanging branches from above usually not visible. In Alaska, also ground-breeding Marmelalke have been observed. Brooding Marmelalke each have two lateral breeding spots. The nestlings hatch after an incubation time of 27 to 30 days. Immediately after hatching, the nestling is brooded continuously for two days. The parent birds feed the nestlings with small fish, which they usually carry zoom individually cross in its beak. The nestling period is 27 to 30 days, then the young bird flies usually unaccompanied by parents birds alone to the sea. It is not yet known how the young birds find their way to the sea. Some young birds can see the sea shortly after they fly away, but others need to travel long distances before they sift through the sea. It is possible that young birds notice the direction of flight of the parent birds, and are based on it.
Stock
All three species are classified by the IUCN as endangered negative mainly the loss of breeding areas act by melting glaciers and marine pollution from ships and oil rigs from. In the wreck of the Exxon Valdez possibly up to 10 percent of the global stock perished.
For the Kamtschatkamarmelalk are no precise population numbers. The IUCN expects that some ten thousand birds of this species exist: During Kamtschatkamarmelalk on the coast of Hokkaido is a rare bird, he is to observe numerous on the coasts of the Sea of Okhotsk. There are several regions in Russia, where it is even considered as a relatively frequent. This includes the estuary of the Amur and the Kamchatka Peninsula. In the region of Sakhalin, the species is much less common. Similar to the Marmelalk this species is threatened mainly by cutting down the old growth forests, to which both species depend as Niststandorte. Even with these two species, the oil pollution and drowning in fishing nets a substantial risk dar.
Species
The following three extant species are counted to the genus Brachyramphus:
- Marmelalk ( Brachyramphus marmoratus )
- Kurzschnabelalk ( Brachyramphus brevirostris )
- Kamtschatkamarmelalk ( Brachyramphus perdix ), sometimes referred to as Langschnabelalk.