Craveri's Murrelet
Encyclopedia
Craveri’s Murrelet 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.
, 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.
, 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.
, rat
s and feral cat
s; this threat has been lessened lately by efforts to restore
its habitat by removing introduced predators.
in Mexico City
, then later at University of Turin
in the city of his birth.
Seabird
Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...
which breeds on offshore islands in both the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
and the Gulf of California
Gulf of California
The Gulf of California is a body of water that separates the Baja California Peninsula from the Mexican mainland...
off the Baja peninsula of Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. It also wanders fairly regularly as far as central California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
in the USA, primarily during post-breeding dispersal. It is threatened by predators introduced
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
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 MurreletXantus's Murrelet
Xantus's Murrelet is a small seabird found in the California Current system in the Pacific Ocean. This auk breeds on islands off California and Mexico...
, 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 herringHerring
Herring is an oily fish of the genus Clupea, found in the shallow, temperate waters of the North Pacific and the North Atlantic oceans, including the Baltic Sea. Three species of Clupea are recognized. The main taxa, the Atlantic herring and the Pacific herring may each be divided into subspecies...
, rockfish
Sebastidae
Sebastidae is a family of marine fish in the order Scorpaeniformes. Their common names include rockfishes, thornyheads and rockcods. Despite the latter name, they are not closely related to the cods in the genus Gadus, nor the rock cod, Lotella rhacina.Not all authorities recognise this family as...
, and lanternfish
Lanternfish
Cooper Lanternfishes are small mesopelagic fish of the large family Myctophidae. One of two families in the order Myctophiformes, the Myctophidae are represented by 246 species in 33 genera, and are found in oceans worldwide. They are aptly named after their conspicuous use of bioluminescence...
. Like all auks it is a wing-propelled diver, chasing down prey under the water with powerful wingbeats. It flies
Bird flight
Flight is the main mode of locomotion used by most of the world's bird species. Flight assists birds while feeding, breeding and avoiding predators....
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
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Synthliboramphus (like the Ancient Murrelet
Ancient Murrelet
The Ancient Murrelet, Synthliboramphus antiquus, is a bird in the auk family. It breeds from the Yellow Sea , 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,...
) the chicks are highly precocial
Precocial
In biology, the term precocial refers to species in which the young are relatively mature and mobile from the moment of birth or hatching. The opposite developmental strategy is called "altricial," where the young are born or hatched helpless. Extremely precocial species may be called...
, 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 miceMICE
-Fiction:*Mice , alien species in The Hitchhiker's Guide to the Galaxy*The Mice -Acronyms:* "Meetings, Incentives, Conferencing, Exhibitions", facilities terminology for events...
, rat
Rat
Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...
s and feral cat
Feral cat
A feral cat is a descendant of a domesticated cat that has returned to the wild. It is distinguished from a stray cat, which is a pet cat that has been lost or abandoned, while feral cats are born in the wild; the offspring of a stray cat can be considered feral if born in the wild.In many parts of...
s; this threat has been lessened lately by efforts to restore
Island restoration
The ecological restoration of islands, or island restoration, is the application of the principles of ecological restoration to islands and island groups. Islands, due to their isolation, are home to many of the world's endemic species, as well as important breeding grounds for seabirds and some...
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 MuseumNational museum
A national museum is a museum maintained by a nation.The following is a list of national museums:-Australia:*Australian National Aviation Museum*Australian National Maritime Museum*, Sydney*Australian War Memorial*Museum Victoria...
in Mexico City
Mexico City
Mexico City is the Federal District , capital of Mexico and seat of the federal powers of the Mexican Union. It is a federal entity within Mexico which is not part of any one of the 31 Mexican states but belongs to the federation as a whole...
, then later at University of Turin
University of Turin
The University of Turin is a university in the city of Turin in the Piedmont region of north-western Italy...
in the city of his birth.
External links
- BirdLife Species Factsheet.
- Stamps (for MexicoMexicoThe United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
) with RangeMap - Craveri's Murrelet photo gallery VIREO
- Photo-Med Res; Article montereyseabirds.com
