>Synthliboramphus wumizusume (Japanese Murrelet)

Japanese Murrelet

Japanese Murrelet
Swimming in Japan
Conservation status
Vulnerable (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Alcidae
Genus:	Synthliboramphus
Species:	S. wumizusume
Binomial name
Synthliboramphus wumizusume Temminck, 1836

The Japanese Murrelet, Synthliboramphus wumizusume also known as Crested Murrelet is a small bird that inhabits rocky islets and reefs in the warm waters of Japan, Russia and South Korea. It has black and bluish grey upper body and white underparts plumage.

Breeding sites are crevices, burrows and hollows in rocks, the gaps in piles of stones, and among grasses on uninhabited islands. The northern limit of the breeding sites are the Nanatsujima Islands of Japan, while the most important breeding sites are Biro Island and the Izu Islands.

The Japanese Murrelet lays eggs in March. Clutch size is slightly less than two eggs. Incubation duty was shared almost equally by both parents. The chicks are not fed in the nest, but leave the nest one to two nights after hatching.

In 1975, this species was designated a natural treasure by Japanese government. Habitat disturbance due to increasing sport fishing activities, predation by crows, large gulls and rats among others, gives the Japanese Murrelet its Vulnerable status on IUCN Red List of Threatened Species. It is listed on Appendix I of CITES and legally protected in Japan.

>Synthliboramphus antiquus (Ancient Murrelet)

Ancient Murrelet

Ancient Murrelet
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Alcidae
Genus:	Synthliboramphus
Species:	S. antiquus
Binomial name
Synthliboramphus antiquus (Gmelin, 1789)

The Ancient Murrelet, Synthliboramphus antiquus, is a bird in the auk family. It breeds from the Yellow Sea (islands off China), through the Russian Pacific coast and the Aleutian Islands to the Haida Gwaii archipelago of British Columbia, where about half of the world population breeds.

These birds breed in colonies, their two eggs (sometimes one) are laid in burrows excavated in forest soil among tree roots, under logs or in grass tussocks, occasionally in rock crevices. These small auks arrive at and depart from their nesting grounds at night, presumably to reduce predation, and perhaps for the same reason the young are never fed at the nest, being taken to sea 1-3 days after hatching. The parents and young recognise one another by call and after the chicks have run from the burrow to the sea, they locate their parents by call and the entire family swims immediately out at sea. The family continues to move away from land for at least twelve hours. After that, the young are fed exclusively at sea by their parents for more than a month.

Some Ancient Murrelets move south in winter as far as California, and odd birds are found inland in North America, carried by autumn storms. The most remarkable record of this relatively short-distance Pacific migrant was a bird found on Lundy, Devon in spring 1990. Even more remarkably, the same bird returned to this British island the following spring.

This small auk species is black on the head, throat and rear neck, grey-backed, and has white underparts. The yellow bill is short and stubby. It has a small rounded black tail. The summer adults have white head streaks giving an aged look and leading to the English name. Other plumages are similar, but lack the crown streaks and black on the throat.

Ancient Murrelets tend to bank from side to side in flight to a greater extent than other small auks. They fly with fast wing beats due to their short wings. Like other auks, Ancient Murrelets forage by swimming underwater using their wings for propulsion. Their diet is poorly known. In winter it consists mainly of crustacea, while in summer both small fish, and crustaceans are taken. Based on stable isotope analysis, their diet in Haida Gwaii seems to consist primarily of small mesopelagic fish. 

The Ancient Murrelet is listed as of 'Special Concern' by the Committee on the Status of Endangered Wildlife in Canada because populations have been greatly reduced over the past century by mammalian predators introduced to their breeding islands. Some recent restoration work is helping to reverse this trend.

>Synthliboramphus craveri (Craveri's Murrelet)

Craveri's Murrelet

 

Craveri’s Murrelet
Conservation status
Vulnerable (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Alcidae
Genus:	Synthliboramphus
Species:	S. craveri
Binomial name
Synthliboramphus craveri (Salvadori, 1865)

Craveri’s Murrelet (Synthliboramphus craveri) is a small seabird which breeds on offshore islands in both the Pacific Ocean and the Gulf of California off the Baja peninsula of Mexico. It also wanders fairly regularly as far as central California in the USA, primarily during post-breeding dispersal. It is threatened by predators introduced to its breeding colonies by oil spills, and tanker traffic. Increasing tourism development and commercial fishing fleets also further threaten the species. With an estimated population of 6,000-10,000 breeding pairs, its population is listed as vulnerable.

Description and range

The Craveri’s Murrelet is a small black and white auk with a small head and thin sharp bill. It resembles the closely related Xantus's Murrelet, with which it shares the distinction of being the most southerly living of all the auk species. The Craveri’s Murrelet has a partial neck collar (Xantus’s has none), and dusky underwings (Xantus’s has white underwings). Craver’s black face mask dips a bit further down the face compared to the Xantus’s. Both species can be also separated by voice.

Behaviour

Craveri's Murrelet feeds far out at sea on larval fish such as herring, rockfish, and lanternfish. Like all auks it is a wing-propelled diver, chasing down prey under the water with powerful wingbeats. It flies well, and can take off without taxiing.

The Craveri's Murrelet nests in small crevices, caves and under dense bushes on arid islands in loose scattered colonies. It returns to the colony only at night, laying two eggs which are incubated for about a month. Like other murrelets of the genus Synthliboramphus (like the Ancient Murrelet) the chicks are highly precocial, leaving the nest within two days of hatching and running actively towards the sea, where the parents call to them. Once at sea the family swims to offshore waters. Little is known about the time at sea due to difficulties in studying them.

Threats

Craveri's Murrelet is considered by some to be one of the more endangered species of auk. It is threatened by offshore oil drilling and tanker traffic. Increased tourist developments and birds getting caught in nets from commercial fishing operations also pose a danger. It is also threatened by introduced species such as mice, rats and feral cats; this threat has been lessened lately by efforts to restore its habitat by removing introduced predators.

Name

The bird is named for Frederico Craveri (1815-1890), an Italian chemist and meteorologist who was a professor at the National Museum inMexico City, then later at University of Turin in the city of his birth.

>Synthliboramphus hypoleucus (Xantus's Murrelet)

Xantus's Murrelet

Xantus's Murrelet
Conservation status
Vulnerable (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Subclass:	Neornithes
Order:	Charadriiformes
Suborder:	Lari
Family:	Alcidae
Genus:	Synthliboramphus
Species:	S. hypoleucus
Binomial name
Synthliboramphus hypoleucus (Xantus, 1859)

Xantus's Murrelet (Synthliboramphus hypoleucus) is a small seabird found in the California Current system in the Pacific Ocean. This auk breeds on islands off California and Mexico. It is threatened by predators introduced to its breeding colonies and by oil spills.

The species is named for the Hungarian ornithologist John Xantus de Vesey who described it from specimens collected off Baja California.

Description and range

This species is a small black and white auk with a small head and thin sharp bill. It resembles the closely related Craveri's Murrelet, with which it shares the distinction of being the most southerly living of all the auk species. It breeds on islands in the Channel Islands of California, the largest colonies being on the Coronado Islands  and on Santa Barbara Island, and also several islands off Baja California, including Isla Guadalupe. After the breeding season it disperses north at sea, usually to offshore waters, as far as British Columbia.

Behaviour

The Xantus's Murrelet's chicks leave the nest for the ocean at just two days old.

Xantus's Murrelet feeds far out at sea, often in association with large pelagic predatory fish like tuna, on larval fish like anchovies, sardines and Sebastes rockfish. Like all auks it is a wing-propelled diver, chasing down prey under the water with powerful wingbeats. There is some speculation that it may feed cooperatively in pairs, as it is almost always observed in pairs, even during the non-breeding season. It flies well, and can take off without taxiing.

It nests in small crevices, caves and under dense bushes on arid islands in loose scattered colonies. It returns to the colony only at night, laying two eggs which are incubated for about a month. Like other synthliboramphine murrelets (e.g. the Ancient Murrelet) the chicks are highly precocial, leaving the nest within two days of hatching and running actively towards the sea, where the parents call to them. Once at sea the family swims to offshore waters.

Little is known about the time at sea due to difficulties in studying them. A female shot at Isla Guadalupe at the end of June was moulting its primary remiges (flight feathers) and unable to fly.

Status and conservation

By the end of the 20th century, Xantus's Murrelet was considered to be among the most endangered species of auk. This has changed since, but not because the present species' status has improved, but because other auks (e.g. Kittlitz's Murrelet) have become rarer. The species is currently classified as Vulnerable (VU B2ab(iv,v); C2a(ii)) by the IUCN^.

Xantus's Murrelet is mainly threatened by oil spills, as much of its population lives near the busy shipping lanes connecting Los Angeles to other ports. Because a large part of its small population nests in such a small area a single catastrophic oil spill could have far reaching implications. It is also threatened by introduced species such as rats and feral cats; this threat has been lessened lately by efforts to restore its habitat by removing introduced predators. In one case the population of rats was removed from Anacapa Island by the use of poisoned bait, the money for which being paid by a trust fund from an oil spill settlement.

>>Genus Synthliboramphus

Synthliboramphus

Synthliboramphus
Ancient Murrelet
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Alcidae
Genus:	Synthliboramphus Brandt, 1837
Species
S. hypoleucus S. craveri S.antiquus S. wumizusume
Synonyms
Endomychura

Synthliboramphus is a small genus of seabirds in the auk family from the North Pacific. It consists of four species:

• Xantus's Murrelet, Synthliboramphus hypoleucus
• Craveri's Murrelet, Synthliboramphus craveri
• Ancient Murrelet, Synthliboramphus antiquus
• Japanese Murrelet, Synthliboramphus wumizusume

The first two species were formally considered conspecific, and are sometimes separated in the genus Endomychura.

Fossil remains of two prehistoric species are known: an undescribed Synthliboramphus sp. from the Late Miocene or Early Pliocene (c. 5 mya) of Cedros Island, Mexico, andSynthliboramphus rineyi from the Late Pliocene (around 3.5-2 mya) San Diego Formation of the southwestern USA.

These birds breed in colonies, their eggs being laid directly amongst tree roots or in rock crevices. They are nocturnal on the breeding grounds, presumably to reduce predation, and for the same reason the precocial young are never fed at the nest, being taken to sea a couple of days after hatching. The parents call to the young from out at sea, and the chicks swim towards the adults who keep moving further out throughout the night.

Synthliboramphus species disperse out to sea after breeding, with northern species migrating further south.

Synthliboramphus auks are small, with mainly black upper parts and white the short wings. These birds forage for food like other auks, by swimming underwater. They mainly eat fish, also some crustaceans and other small invertebrates.