Revillagigedo Islands
Encyclopedia
Island
An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...
s in 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...
, known for their unique ecosystem. They have been part of Manzanillo
Manzanillo, Colima
The name Manzanillo refers to the city as well as its surrounding municipality in the Mexican state of Colima. The city, located on the Pacific Ocean, contains Mexico's busiest port. Manzanillo was the third port created by the Spanish in the Pacific during the New Spain period...
municipality
Municipalities of Colima
The Mexican state of Colima is divided into ten municipalities :...
of the Mexican
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...
state of Colima
Colima
Colima is one of the 31 states which, with the Federal District, make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima....
since 1861, but are nevertheless under Mexican federal jurisdiction, and lie 386 km southwest of Cabo San Lucas
Cabo San Lucas
Cabo San Lucas , commonly called Cabo, is a city at the southern tip of the Baja California peninsula, in the municipality of Los Cabos in the Mexican state of Baja California Sur. As of the 2010 census, the population was 68,463 people...
, the southern tip of Baja California peninsula
Baja California Peninsula
The Baja California peninsula , is a peninsula in northwestern Mexico. Its land mass separates the Pacific Ocean from the Gulf of California. The Peninsula extends from Mexicali, Baja California in the north to Cabo San Lucas, Baja California Sur in the south.The total area of the Baja California...
, and between 720 and 970 km west of Manzanillo
Manzanillo, Colima
The name Manzanillo refers to the city as well as its surrounding municipality in the Mexican state of Colima. The city, located on the Pacific Ocean, contains Mexico's busiest port. Manzanillo was the third port created by the Spanish in the Pacific during the New Spain period...
. They are located around 18°49′N 112°46′W.
Geography
Socorro Island
Socorro Island is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying some 600 kilometers off the country's western coast at 18°48'N, 110°59'W. The size is 16.5 by 11.5 km, with an area of 132 km².- Geology :...
, with a population of 250 (staff and families). On Clarión
Clarion Island
Isla Clarión, formerly called Santa Rosa, is the second largest, westernmost and most remote of the Revillagigedo Islands, west of Socorro Island and over from the Mexican mainland and an area ². It has three prominent peaks. The westernmost and tallest peak, Monte Gallegos, is high...
, there is a small naval garrison with 9 men. The islands are otherwise uninhabited. The islands are named after Don
Don (honorific)
Don, from Latin dominus, is an honorific in Spanish , Portuguese , and Italian . The female equivalent is Doña , Dona , and Donna , abbreviated "Dª" or simply "D."-Usage:...
Juan Vicente de Güemes, 2nd Count of Revillagigedo, the 53rd viceroy of New Spain
New Spain
New Spain, formally called the Viceroyalty of New Spain , was a viceroyalty of the Spanish colonial empire, comprising primarily territories in what was known then as 'América Septentrional' or North America. Its capital was Mexico City, formerly Tenochtitlan, capital of the Aztec Empire...
.
| Island (Alternate Name) | Length bywidth (km) | Area (km²) | Highest Peak (m) | |
| Inner Islands (UTC-7 UTC-7 thumb|300px|UTC−07: Blue , Orange , Yellow , Light Blue - Sea areasUTC−07:00 is an identifier for a time offset from UTC of −07.... , Pacific Time Zone Mountain Time Zone The Mountain Time Zone of North America keeps time by subtracting seven hours from Coordinated Universal Time, also known as Greenwich Mean Time, during the shortest days of autumn and winter , and by subtracting six hours during daylight saving time in the spring, summer, and early autumn... ) |
||||
| San Benedicto San Benedicto Island San Benedicto, formerly Santo Tomás, is an uninhabited island, and third largest island of the Revillagigedo Islands, located in the Pacific at .... (San Tomás) |
4.315 by 2.490 | 5.94 | Bárcena (310) | |
| Socorro Socorro Island Socorro Island is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying some 600 kilometers off the country's western coast at 18°48'N, 110°59'W. The size is 16.5 by 11.5 km, with an area of 132 km².- Geology :... |
16.813 by 15.629 | 132.06 | Mount (Cerro) Evermann (1130) | |
| Roca Partida Roca Partida Roca Partida is the smallest of the Revillagigedo Islands in Mexico, administrated by the state of Colima. It is uninhabited, with an area of only .... |
0.246 by 0.073 | 0.014 | (34) | |
| (Outer Island) (UTC-8 UTC-8 UTC−08:00 is an identifier for a time offset from UTC of −08. This time is used in:-As standard time :*Canada**Northwest Territories***Tungsten and the associated Cantung Mine*Mexico... , Northwest Time Zone Pacific Time Zone The Pacific Time Zone observes standard time by subtracting eight hours from Coordinated Universal Time . The clock time in this zone is based on the mean solar time of the 120th meridian west of the Greenwich Observatory. During daylight saving time, its time offset is UTC-7.In the United States... ) |
||||
| Clarión Clarion Island Isla Clarión, formerly called Santa Rosa, is the second largest, westernmost and most remote of the Revillagigedo Islands, west of Socorro Island and over from the Mexican mainland and an area ². It has three prominent peaks. The westernmost and tallest peak, Monte Gallegos, is high... (Santa Rosa) |
8.544 by 3.686 | 19.80 | Monte Gallegos (335) | |
| Revillagigedo Islands | 420 by 115 | 157.81 | Mount (Cerro) Evermann (1130) | |
The three eastern islands are called the inner islands. They fall in the time zone
Time zone
A time zone is a region on Earth that has a uniform standard time for legal, commercial, and social purposes. In order for the same clock time to always correspond to the same portion of the day as the Earth rotates , different places on the Earth need to have different clock times...
UTC-7
UTC-7
thumb|300px|UTC−07: Blue , Orange , Yellow , Light Blue - Sea areasUTC−07:00 is an identifier for a time offset from UTC of −07....
(Mountain Time
Mountain Time Zone
The Mountain Time Zone of North America keeps time by subtracting seven hours from Coordinated Universal Time, also known as Greenwich Mean Time, during the shortest days of autumn and winter , and by subtracting six hours during daylight saving time in the spring, summer, and early autumn...
), while the major part of Colima
Colima
Colima is one of the 31 states which, with the Federal District, make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima....
is UTC-6
UTC-6
UTC−06 is an identifier for a time offset from UTC of −06. This time is used in:-Central America:*Belize*Costa Rica*El Salvador*Guatemala*Honduras*Nicaragua-Central Standard Time:...
(Central Time Zone
Central Time zone
In North America, the Central Time Zone refers to national time zones which observe standard time by subtracting six hours from UTC , and daylight saving, or summer time by subtracting five hours...
). Clarión is comparatively far to the west, by more than 200 km in comparison with the inner islands, and in UTC-8
UTC-8
UTC−08:00 is an identifier for a time offset from UTC of −08. This time is used in:-As standard time :*Canada**Northwest Territories***Tungsten and the associated Cantung Mine*Mexico...
(Pacific Time Zone
Pacific Time Zone
The Pacific Time Zone observes standard time by subtracting eight hours from Coordinated Universal Time . The clock time in this zone is based on the mean solar time of the 120th meridian west of the Greenwich Observatory. During daylight saving time, its time offset is UTC-7.In the United States...
). The Revillagigedo Islands are one of three Mexican island groups in the Pacific Ocean that are not on the continental shelf
Continental shelf
The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...
; the others are Guadalupe Island
Guadalupe Island
Guadalupe Island, or Isla Guadalupe is a volcanic island located 241 kilometers off the west coast of Mexico's Baja California peninsula and some 400 kilometers southwest of the city of Ensenada in Baja California state, in the Pacific Ocean...
and Rocas Alijos
Rocas Alijos
Rocas Alijos are a group of tiny, steep and barren volcanic islets or above-water rocks in the Pacific Ocean at . They are part of Comondú municipality of the Mexican state of Baja California Sur, and situated about 300 km west of the mainland. The total surface area is less than...
.
Sixteenth to nineteenth century
No evidence of human habitation on Socorro exists before its discovery by Spanish explorers. Hernando de Grijalva and his crew discovered an uninhabited island on December 28, 1533, and named it Isla de los Inocentes, only nine days after the discovery of Santo Tomé island. The description and location may correspond to that of San BenedictoSan Benedicto Island
San Benedicto, formerly Santo Tomás, is an uninhabited island, and third largest island of the Revillagigedo Islands, located in the Pacific at ....
.
In 1542, Ruy López de Villalobos
Ruy López de Villalobos
Ruy López de Villalobos was a Spanish explorer who sailed the Pacific from Mexico to establish a permanent foothold for Spain in the East Indies, which was near the Line of Demarcation between Spain and Portugal according to the Treaty of Saragossa in 1529...
, while exploring new routes across the Pacific, rediscovered Inocentes and changed its name to Anublada ("Cloudy"). In 1608, Martín Yañez de Armida, in charge of another expedition, visited Anublada and changed its name to Socorro. The other two islands were discovered in 1779 by José Camacho. He named the small rocky islet in the middle of the Archipelago Roca Partida ("Broken Rock"), and the westernmost island Santa Rosa ("Saint Rose"). Santa Rosa was later renamed Clarion after the vessel commanded by Henry Gyzelaar at that time. Santo Tomás is called San Benedicto ("Saint Benedict") today.
The Revillagigedo Islands have been visited by a number of other explorers: Domingo del Castillo (1541), Miguel Pinto (1772), Alexander von Humboldt
Alexander von Humboldt
Friedrich Wilhelm Heinrich Alexander Freiherr von Humboldt was a German naturalist and explorer, and the younger brother of the Prussian minister, philosopher and linguist Wilhelm von Humboldt...
(1811), Benjamin Morrell
Benjamin Morrell
Benjamin Morrell was an American sealing captain and explorer who between 1823 and 1831 made a series of voyages, mainly to the Southern Ocean and the Pacific Islands, which are recorded in a colourful memoir A Narrative of Four Voyages...
(1825), Sir Edward Belcher
Edward Belcher
Admiral Sir Edward Belcher, KCB , was a British naval officer and explorer. He was the great-grandson of Governor Jonathan Belcher. His wife, Diana Jolliffe, was the stepdaughter of Captain Peter Heywood.-Early life:...
(1839) who made the first botanical collections and Reeve, who witnessed the eruption of Mount Evermann in 1848. On 25 July 1861, President
President of Mexico
The President of the United Mexican States is the head of state and government of Mexico. Under the Constitution, the president is also the Supreme Commander of the Mexican armed forces...
Benito Juárez
Benito Juárez
Benito Juárez born Benito Pablo Juárez García, was a Mexican lawyer and politician of Zapotec origin from Oaxaca who served five terms as president of Mexico: 1858–1861 as interim, 1861–1865, 1865–1867, 1867–1871 and 1871–1872...
signed a decree awarding territorial control over the four islands to the state of Colima
Colima
Colima is one of the 31 states which, with the Federal District, make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima....
. His plan was to build an offshore penitentiary on Isla Socorro; although this never happened, the decree whereby they were attached to Colima has never been repealed. In 1865, the island was explored by ornithologist Andrew Jackson Grayson
Andrew Jackson Grayson
Andrew Jackson Grayson was an American ornithologist and artist.Grayson was the author of Birds of the Pacific Slope , which he considered to be a completion of John James Audubon's Birds of America...
, who discovered the Socorro Dove
Socorro Dove
The Socorro Dove is a dove that is extinct in the wild. It was endemic to Socorro Island in the Revillagigedo Islands off the west coast of Mexico. The last sighting in its natural habitat was in 1972. There are not more than 200 and probably fewer than 100 purebred birds in captivity...
and the Socorro Elf Owl which were later given scientific names in his honor.
Twentieth century
Barton Warren Evermann
Barton Warren Evermann was an American ichthyologist. He was born in Monroe County, Iowa, and graduated from Indiana University in 1886. For 10 years, he served as teacher and superintendent of schools in Indiana and California. He was professor of biology at the Indiana State University in...
, director of the California Academy of Sciences
California Academy of Sciences
The California Academy of Sciences is among the largest museums of natural history in the world. The academy began in 1853 as a learned society and still carries out a large amount of original research, with exhibits and education becoming significant endeavors of the museum during the twentieth...
in San Francisco, California
San Francisco, California
San Francisco , officially the City and County of San Francisco, is the financial, cultural, and transportation center of the San Francisco Bay Area, a region of 7.15 million people which includes San Jose and Oakland...
, promoted the scientific exploration of the islands. The most comprehensive biological collections were obtained at this time. The volcano on Isla Socorro was renamed in his honor. In 1957 the Mexican Navy established a naval base on Socorro and has had a permanent presence on the island since then. A tiny outpost also exists on Clarión, as noted above. On 21 March 1972, Pablo Silva García became the first governor of Colima to visit his state's island territories. A plaque was unveiled to mark the event and cement Colima's claim.
The seas surrounding the larger islands are popular with scuba divers
Scuba diving
Scuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater....
; a variety of marine life such as cetaceans, shark
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
s and manta ray
Manta ray
The manta ray is the largest species of the rays. The largest known specimen was more than across, with a weight of about . It ranges throughout waters of the world, typically around coral reefs...
s can be observed. Visitors usually stay aboard expedition vessels during their visit to the islands, which is desirable from an ecological standpoint to prevent introduction of further invasive species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
.
The islands are occasionally visited by amateur radio
Amateur radio
Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
operators, who usually use the ITU prefix
ITU prefix
The International Telecommunication Union allocates call sign prefixes for radio and television stations of all types. They also form the basis for, but do not exactly match, aircraft registration identifiers. These prefixes are agreed upon internationally, and are a form of country code...
XF4. Because of their distance from the mainland, for award credit they are considered to be an "entity" separate from Mexico. Expeditions from organizations engaged in biological conservation
Conservation biology
Conservation biology is the scientific study of the nature and status of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction...
of the islands visit the islands for fieldwork on a regular basis. No tourism
Tourism
Tourism is travel for recreational, leisure or business purposes. The World Tourism Organization defines tourists as people "traveling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes".Tourism has become a...
facilities exist; the islands have no reliable sources of fresh water of their own.
Ecology
The Revillagigedo Islands are home to many endemicEndemic (ecology)
Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
plant and animal species, and are sometimes called Mexico's "little Galapagos
Galápagos Islands
The Galápagos Islands are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, west of continental Ecuador, of which they are a part.The Galápagos Islands and its surrounding waters form an Ecuadorian province, a national park, and a...
". They are recognized as a distinct terrestrial ecoregion, part of the Neotropic
Neotropic
In biogeography, the Neotropic or Neotropical zone is one of the eight terrestrial ecozones. This ecozone includes South and Central America, the Mexican lowlands, the Caribbean islands, and southern Florida, because these regions share a large number of plant and animal groups.It is sometimes used...
ecozone
Ecozone
An ecozone is the broadest biogeographic division of the Earth's land surface, based on distributional patterns of terrestrial organisms.Ecozones delineate large areas of the Earth's surface within which organisms have been evolving in relative isolation over long periods of time, separated from...
. Socorro is the most diverse in flora, fauna, and topography. The Mexican Government established the islands as a Biosphere Reserve
Biosphere reserve
The Man and the Biosphere Programme of UNESCO was established in 1971 to promote interdisciplinary approaches to management, research and education in ecosystem conservation and sustainable use of natural resources.-Development:...
on June 4, 1994.
World Wide Fund for Nature
The World Wide Fund for Nature is an international non-governmental organization working on issues regarding the conservation, research and restoration of the environment, formerly named the World Wildlife Fund, which remains its official name in Canada and the United States...
, (http://www.worldwildlife.org/wildworld/profiles/terrestrial/nt/nt0216_full.html?iframe=true&width=100%&height=100%) 14 of the islands' 16 generally accepted resident taxa of landbirds as well as one seabird
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...
are endemic, as are all of the islands' native terrestrial vertebrates. The latter, however, consist only of one Masticophis
Masticophis
Masticophis is a genus of colubrid snakes that are commonly referred to as whip snakes or coachwhips. They are characterized by having a long, thin body and are not dangerous.- Species :...
whipsnake and two Urosaurus
Urosaurus
The North American genus Urosaurus belongs to the New World Iguanian family Phrynosomatidae. They can be distinguished from members of the genus Sceloporus by the presence of a gular fold and granular lateral scales...
iguanids. Numerous seabird
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...
taxa breed no further north(east)wards than San Benedicto; storm-petrel
Storm-petrel
Storm petrels are seabirds in the family Hydrobatidae, part of the order Procellariiformes. These smallest of seabirds feed on planktonic crustaceans and small fish picked from the surface, typically while hovering. The flight is fluttering and sometimes bat-like.Storm petrels have a cosmopolitan...
s are notably absent as breeders though they breed in the region and visit the islands to forage. Albatross
Albatross
Albatrosses, of the biological family Diomedeidae, are large seabirds allied to the procellariids, storm-petrels and diving-petrels in the order Procellariiformes . They range widely in the Southern Ocean and the North Pacific...
es are also not normally found here. Among landbirds, the absence of the House Finch
House Finch
The House Finch is a bird in the finch family Fringillidae, which is found in North America. This species and the other "American rosefinches" are usually placed in the rosefinch genus Carpodacus...
, widespread on northeastern Pacific offshore islands, is the most conspicuous one.
Apart from the native birds, migrant
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
shorebirds and others are often found on the islands. Bahia Azufre (Sulfur Bay) on Clarión seems to be a favorite stopover location, as it is one of the few longer stretches of beach in the islands; mostly, the shoreline is steep cliffs.
Socorro has numerous endemic plant taxa, whereas Clarión which is farthest from land has but a few. The San Benedicto was effectively wiped out in the devastating eruption of Bárcena volcano on August 1, 1952, but has since recovered; apparently just the San Benedicto Rock Wren
San Benedicto Rock Wren
The San Benedicto Rock Wren is a small extinct passerine which was endemic to San Benedicto Island in the Revillagigedo Islands off Mexico. It was a subspecies of the Rock Wren.-Extinction:...
became entirely extinct. Most if not all native plants found on San Benedicto today are shared with Clarión, not with the closer Socorro to the south, due to the prevailing winds and ocean current
Ocean current
An ocean current is a continuous, directed movement of ocean water generated by the forces acting upon this mean flow, such as breaking waves, wind, Coriolis effect, cabbeling, temperature and salinity differences and tides caused by the gravitational pull of the Moon and the Sun...
s. The native flora of Clarión is about equally shared with both other large islands.
As opposed to the interchange between the islands, the animals and plants that colonized them initially are apparently all from mainland populations generally to the northeastward of the Revillagigedos. Plants are most often derived from Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
founder populations, whereas the endemic nonavian reptile
Reptile
Reptiles are members of a class of air-breathing, ectothermic vertebrates which are characterized by laying shelled eggs , and having skin covered in scales and/or scutes. They are tetrapods, either having four limbs or being descended from four-limbed ancestors...
s seem to be rather derived directly from mainland populations of the Sonora
Sonora
Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....
-Sinaloa
Sinaloa
Sinaloa officially Estado Libre y Soberano de Sinaloa is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 18 municipalities and its capital city is Culiacán Rosales....
area. The ancestors of the islands' terrestrial birds probably came from the general area of southern North
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and northern Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
. As illustrated by the fact that no endemic landbird taxon occurs on more than one island and the cases of the Socorro
Socorro Wren
The Socorro Wren is a species of bird in the Troglodytidae family.It is endemic to Socorro Island, Mexico. It was formerly placed in Thryomanes but was moved to Troglodytes considering "manners, song, plumage, etc." and by biogeography and mtDNA NADH dehydrogenase subunit 2 sequence analysis.Its...
and Clarión Wren
Clarión Wren
The Clarión Wren is a species of bird in the Troglodytidae family.It is endemic to Clarión Island off Pacific Mexico....
s as well as the Socorro Dove
Socorro Dove
The Socorro Dove is a dove that is extinct in the wild. It was endemic to Socorro Island in the Revillagigedo Islands off the west coast of Mexico. The last sighting in its natural habitat was in 1972. There are not more than 200 and probably fewer than 100 purebred birds in captivity...
and Clarión Mourning Dove
Mourning Dove
The Mourning Dove is a member of the dove family . The bird is also called the Turtle Dove or the American Mourning Dove or Rain Dove, and formerly was known as the Carolina Pigeon or Carolina Turtledove. It is one of the most abundant and widespread of all North American birds...
, each bird population seems to have arisen independently.
Threats and conservation
"The future of the avifauna of the islands appears to be secure at present. There are no human inhabitants, and no mammals of any kind except the moderate and apparently stable population of sheep on Socorro."
The unique ecology of the islands has since then come under threat from these and other exotic species. Sheep were introduced to Socorro in 1869, and cats have become established after 1953, probably in the early 1970s. Pigs were introduced to Clarión in 1979, and rabbits became feral
Feral
A feral organism is one that has changed from being domesticated to being wild or untamed. In the case of plants it is a movement from cultivated to uncultivated or controlled to volunteer. The introduction of feral animals or plants to their non-native regions, like any introduced species, may...
at some earlier date.
Several endemic species of Socorro are now threatened with extinction. The Socorro Mockingbird
Socorro Mockingbird
The Socorro Mockingbird, Mimus graysoni, is an endangered mockingbird endemic to Socorro Island in Mexico's Revillagigedo Islands. The specific epithet commemorates the American ornithologist Andrew Jackson Grayson....
(Mimodes graysoni) numbers less than 400 individuals altogether. The endemics Socorro Parakeet
Socorro Parakeet
The Socorro Parakeet is a subspecies of the Green Parakeet. It was formerly considered a distinct species, and some taxonomists still consider it so. It is endemic to Socorro Island in the Revillagigedo Islands, Mexico. Its natural habitat is subtropical or tropical moist lowland forests...
(Aratinga brevipes) and the Townsend's Shearwater
Townsend's Shearwater
Townsend's Shearwater, Puffinus auricularis, is a rare seabird of the tropics from the family Procellariidae.Its relationships are unresolved. Its closest relatives are probably, but not certainly, the Hawaiian Shearwater and possibly the Manx Shearwater...
(Puffinus auricularis), are also endangered. The Socorro Dove
Socorro Dove
The Socorro Dove is a dove that is extinct in the wild. It was endemic to Socorro Island in the Revillagigedo Islands off the west coast of Mexico. The last sighting in its natural habitat was in 1972. There are not more than 200 and probably fewer than 100 purebred birds in captivity...
(Zenaida graysoni) is now extinct in the wild, but is being bred in captivity. The Elf Owl
Elf Owl
The Elf Owl is a member of the owl family Strigidae that breeds in the southwestern United States and Mexico. It is the world's lightest owl, although the Long-whiskered Owlet and the Tamaulipas Pygmy Owl are of a similarly diminutive length. The mean body weight of this species is 40 grams...
's Socorro subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
Micrathene whitneyi graysoni appears to be extinct. Other plant and animal taxa in the archipelago are also considered threatened or nearly so.
A number of conservation
Habitat conservation
Habitat conservation is a land management practice that seeks to conserve, protect and restore, habitat areas for wild plants and animals, especially conservation reliant species, and prevent their extinction, fragmentation or reduction in range...
initiatives are dedicated to halting the destruction of the native ecosystems of the islands. Dr. Harmunt Walter of the University of California, Los Angeles
University of California, Los Angeles
The University of California, Los Angeles is a public research university located in the Westwood neighborhood of Los Angeles, California, USA. It was founded in 1919 as the "Southern Branch" of the University of California and is the second oldest of the ten campuses...
(UCLA) and Dr. Luis F. Baptista of the California Academy of Sciences
California Academy of Sciences
The California Academy of Sciences is among the largest museums of natural history in the world. The academy began in 1853 as a learned society and still carries out a large amount of original research, with exhibits and education becoming significant endeavors of the museum during the twentieth...
have coordinated breeding and reintroduction efforts for the Socorro Dove since 1988, through the Island Endemics Institute. The Comité Científico para la Conservación y Restauración del Archipiélago Revillagigedo ("Scientific Committee for the Conservation and Restoration of the Revillagigedo Islands") was founded in 1996, and is a committee representing several organizations, including the Island Conservation & Ecology Group, Island Endemics Institute, the University of Missouri–St. Louis
University of Missouri–St. Louis
The University of Missouri–St. Louis is one of four universities in the University of Missouri System. Established in 1963, it is the newest university in the UM System. , it is the largest university by enrollment in the St. Louis area with 16,548 students...
(UMSL), the National Autonomous University of Mexico
National Autonomous University of Mexico
The Universidad Nacional Autónoma de México is a university in Mexico. UNAM was founded on 22 September 1910 by Justo Sierra as a liberal alternative to the Roman Catholic-sponsored Royal and Pontifical University of Mexico The Universidad Nacional Autónoma de México (UNAM) (National Autonomous...
(UNAM) and others. It is chaired by Dr. Walter and Dr. Luis Medrano of UNAM is its secretary. The committee has been advocating removal of the exotic species from the islands, especially the estimated 2000 sheep on Socorro, to allow the islands' ecology to recover, and adoption of a management plan to promote the recovery of the islands' native species, including reintroduction of the Socorro Dove.
Poignantly, Brattstrom and Howell who gave the optimistic outlook in 1956 went on to caution that
"it may be hoped that the Mexican government will guard against the introduction of mammals such as rabbits, cats, goats and others that have invariably brought disaster to the flora and fauna of insular regions."