Isla Clarión, formerly called Santa Rosa, is the second largest, westernmost and most remote of Mexico's

Revillagigedo Islands The Revillagigedo Islands ( es, Islas Revillagigedo, ) or Revillagigedo Archipelago are a group of four volcanic islands in the Pacific Ocean, known for their unique ecosystem. They lie approximately from Socorro Island south and southwest of C ...

. The island is located west of

Socorro Island Socorro Island ( es, Isla Socorro) is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying off the country's western coast. The size is 16.5 by 11.5 km (10.25 by 7.15 miles), with an area of . It is the largest ...

and over from the Mexican mainland. It has an area of and three prominent peaks. The westernmost and tallest peak, ''Monte Gallegos'', is high. The central peak is called ''Monte de la Marina'', , and the eastern peak Pico de la Tienda . The coasts are backed by perpendicular cliffs, high, with the exception of the middle part of the southern coast in the vicinity of ''Bahía Azufre'' (Sulphur Bay), which is the location of a small military garrison with a contingent of 9 soldiers. Two small and at least temporarily

brackish Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estu ...

pools are the only source of fresh water; even these may dry up in summers with little rain. Clarion can only be reached by sea, which from Mexico takes 30 hours.

History

No signs to indicate prehistoric human activity have ever been found on Clarión Island. It was visited in late 1542 by the Spanish navigator

Ruy López de Villalobos Ruy López de Villalobos (; ca. 1500 – April 4, 1546) 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 a ...

, but with the exception of a possible re-sighting of the Revillagigedos by Juan Fernández de Ladrillero before 1574 and a short-lived residence by the adventurer Martín Yáñez de Armida on the island he later renamed Socorro (1606), the archipelago was neglected by the Spaniards.

Joris van Spilbergen Joris van Spilbergen (1568 in Antwerp – January 31, 1620 in Bergen op Zoom) was a Dutch naval officer. Joris van Spilbergen was born in Antwerp in 1568. His first major expedition was in 1596, when he sailed to Africa. He then left for As ...

's sighting of the whole group in December 1615 seems not to have been noted in Spain or its American colonies. Clarion was sighted again by the English privateer George Shelvocke on the ''Speedwell'', August 21, 1721. The name of the island goes back to the American brig ''Clarion'', Capt. Henry Gyzelaar, who was engaged in the North Pacific trade around 1820. The ''Handbook of Selected Pacific Islands'' (1959), by Edwin B. Doran, observed that "Clarion has never been occupied by man for more than a few days at a time", adding that "there are no facilities of any sort at present."

Ecology

As the

topography Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary sc ...

of Clarión lacks any prominent peaks that could induce rains like Cerro Evermann on

, the island is

semiarid A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi- ...

arid A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most ...

all over. Consequently, the whole of the island is covered in shrubland,

grassland A grassland is an area where the vegetation is dominated by grasses ( Poaceae). However, sedge ( Cyperaceae) and rush ( Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur na ...

Tapertip Cupgrass (''

Eriochloa ''Eriochloa'' is a widespread genus of plants in the grass family, commonly called cupgrass. They are found across much of Africa, Asia, Australia, and the Americas, plus a few places in European Russia. ; Species * ''Eriochloa acuminata'' &ndas ...

acuminata''), Madagascar Dropseed (''

Sporobolus ''Sporobolus'' is a nearly cosmopolitan genus of plants in the grass family. The name ''Sporobolus'' means "seed-thrower", and is derived from Ancient Greek word (), meaning "seed", and the root of () "to throw", referring to the dispersion of ...

pyramidatus''), and endemic ''

Aristida ''Aristida'' is a very nearly cosmopolitan genus of plants in the grass family. ''Aristida'' is distinguished by having three awns (bristles) on each lemma of each floret. The genus includes about 300 species found worldwide, often in arid warm ...

tenuifolia'': CMICD (2007) and '' Opuntia''Probably related to Engelmann's Prickly Pear (''O. engelmannii''): Brattstrom & Howell (1956) cacti. Far away from land,

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

taxa In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

are fewer than on Socorro but like there mainly consist of landbirds and plants. Rabbits and

feral A feral () animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some ...

sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to domesticated ...

are found on the island and have caused serious harm to the local vegetation; pigs introduced in 1979 have caused harm to the local

fauna Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is ''funga''. Flora, fauna, funga and other forms of life are collectively referred to as ''Biota (ecology ...

. Native

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () (chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, with c ...

s – except birds – are limited to two snake species and one

iguanid The Iguanidae is a family of lizards composed of the iguanas, chuckwallas, and their prehistoric relatives, including the widespread green iguana. Taxonomy Iguanidae is thought to be the sister group to the collared lizards (family Crotaphy ...

lizard species, both endemic. A few

seabird Seabirds (also known as marine birds) are birds that are 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 enviro ...

species breed on Clarión or formerly did so. The island is near the north(east)ern limit of the breeding range of several of these, but their continued presence needs confirmation: *

Nazca booby The Nazca booby (''Sula granti'') is a large seabird of the booby family, Sulidae, native to the eastern Pacific. First described by Walter Rothschild in 1902, it was long considered a subspecies of the masked booby until recognised as distinct ...

, ''Sula granti'' * East Pacific red-footed booby, ''Sula sula websteri'' – a doubtfully distinct subspecies * East Pacific great frigatebird, ''Fregata minor ridgwayi'' – breeding suspected but not verified; a doubtfully distinct subspecies For reasons not fully known, Clarión seems to be more attractive to

shorebird 245px, A flock of Dunlins and Red knots">Red_knot.html" ;"title="Dunlins and Red knot">Dunlins and Red knots Waders or shorebirds are birds of the order Charadriiformes commonly found wikt:wade#Etymology 1, wading along shorelines and mudflat ...

s and other vagrant or migrant birds than Socorro; perhaps this is due to the presence of

red-tailed hawk The red-tailed hawk (''Buteo jamaicensis'') is a bird of prey that breeds throughout most of North America, from the interior of Alaska and northern Canada to as far south as Panama and the West Indies. It is one of the most common members wit ...

s on the latter island. Great blue heron, snowy egret,

white-faced ibis The white-faced ibis (''Plegadis chihi'') is a wading bird in the ibis family, Threskiornithidae. This species breeds colonially in marshes, usually nesting in bushes or low trees. Its breeding range extends from the western United States south ...

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...

and possibly

American golden plover The American golden plover (''Pluvialis dominica''), is a medium-sized plover. The genus name is Latin and means relating to rain, from ''pluvia'', "rain". It was believed that golden plovers flocked when rain was imminent. The species name ''d ...

spotted sandpiper The spotted sandpiper (''Actitis macularius'') is a small shorebird. Together with its sister species the common sandpiper (''A. hypoleucos''), it makes up the genus ''Actitis''. They replace each other geographically; stray birds may settle do ...

wandering tattler The wandering tattler (''Tringa incana''; formerly ''Heteroscelus incanus'': Pereira & Baker, 2005; Banks ''et al.'', 2006), is a medium-sized wading bird. It is similar in appearance to the closely related gray-tailed tattler, ''T. brevipes''. ...

ruddy turnstone The ruddy turnstone (''Arenaria interpres'') is a small cosmopolitan wading bird, one of two species of turnstone in the genus ''Arenaria''. It is now classified in the sandpiper family Scolopacidae but was formerly sometimes placed in the plov ...

, black-necked stilt,

western gull The western gull (''Larus occidentalis'') is a large white-headed gull that lives on the west coast of North America. It was previously considered conspecific with the yellow-footed gull (''Larus livens'') of the Gulf of California. The western ...

and

barn swallow The barn swallow (''Hirundo rustica'') is the most widespread species of swallow in the world. In fact, it appears to have the largest natural distribution of any of the world's passerines, ranging over 251 million square kilometres globally. ...

are examples of the species that can be encountered on Clarión with some regularity; most of the shorebirds congregate in the sheltered shallows of Sulphur Bay. Others, such as

blue-winged teal The blue-winged teal (''Spatula discors'') is a species of bird in the duck, goose, and swan family Anatidae. One of the smaller members of the dabbling duck group, it occurs in North America, where it breeds from southern Alaska to Nova Scoti ...

western sandpiper The western sandpiper (''Calidris mauri'') is a small shorebird. The genus name is from Ancient Greek ''kalidris'' or ''skalidris'', a term used by Aristotle for some grey-coloured waterside birds. The specific ''mauri'' commemorates Italian bota ...

least sandpiper The least sandpiper (''Calidris minutilla'') is the smallest shorebird. The genus name is from Ancient Greek ''kalidris'' or ''skalidris'', a term used by Aristotle for some grey-colored waterside birds. The specific ''minutilla'' is Medieval Lat ...

short-eared owl The short-eared owl (''Asio flammeus'') is a widespread grassland species in the family Strigidae. Owls belonging to genus ''Asio'' are known as the eared owls, as they have tufts of feathers resembling mammalian ears. These "ear" tufts may or ...

, belted kingfisher,

northern mockingbird The northern mockingbird (''Mimus polyglottos'') is a mockingbird commonly found in North America. This bird is mainly a permanent resident, but northern birds may move south during harsh weather. This species has rarely been observed in Europe ...

and

brown-headed cowbird The brown-headed cowbird (''Molothrus ater'') is a small, obligate brood parasitic icterid native to temperate and subtropical North America. It is a permanent resident in the southern parts of its range; northern birds migrate to the southern ...

have only been recorded on very few occasions, sometimes only once. Clarion angelfish (Holacanthus clarionensis) (19185438555)

Endemic animals

* Clarión

burrowing owl The burrowing owl (''Athene cunicularia''), also called the shoco, is a small, long-legged owl found throughout open landscapes of North and South America. Burrowing owls can be found in grasslands, rangelands, agricultural areas, deserts, or an ...

, ''Athene cunicularia rostrata'' *

Clarión wren The Clarión wren (''Troglodytes tanneri'') is a species of bird in the family Troglodytidae. It is endemic to Clarión Island off Pacific Mexico. It looks much like a house wren but is larger with a prominently longer bill, somewhat approachi ...

, '' Troglodytes tanneri'' ( vulnerable) * Clarión

mourning dove The mourning dove (''Zenaida macroura'') is a member of the dove family, Columbidae. The bird is also known as the American mourning dove, the rain dove, and colloquially as the turtle dove, and was once known as the Carolina pigeon and Caroli ...

, ''Zenaida macroura clarionensis'' * Clarion Island whipsnake, ''Masticophis anthonyi'' * ''Urosaurus clarionensis'' Clarion Owl - February 1997

* Clarión nightsnake, '' Hypsiglena unaocularis'' In addition, the local population of the

western raven The common raven (''Corvus corax'') is a large all-black passerine bird. It is the most widely distributed of all corvids, found across the Northern Hemisphere. It is a raven known by many names at the subspecies level; there are at least e ...

(''Corvus corax sinuatus'' or ''C. sinuatus'') was formerly considered a distinct subspecies ''clarionensis'', but this is not usually accepted at present. It can be expected that this question will soon be resolved as there is currently renewed interest in the

phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spe ...

of the common/western/

Chihuahuan raven The Chihuahuan raven (''Corvus cryptoleucus'') is a species of crow in the family Corvidae that is native to the United States and Mexico. Description The proportions resemble the common raven with a heavy bill, but is about the same size as a c ...

s. If the Revillagigedos population is indeed distinct, it might be endemic of Clarión as the only other local

subpopulation In statistics, a population is a Set (mathematics), set of similar items or events which is of interest for some question or experiment. A statistical population can be a group of existing objects (e.g. the set of all stars within the Milky Way g ...

, on San Benedicto, was destroyed by a volcanic eruption on August 1, 1952; on the other hand, mainland birds have sometimes been assigned to ''clarionensis'' also. The Clarión population of the critically endangered

Townsend's shearwater Townsend's shearwater (''Puffinus auricularis'') is a rare seabird of the tropics from the family Procellariidae. Taxonomy Its relationships are unresolved. Its closest relatives are probably, but not certainly, the Hawaiian shearwater (''Puffi ...

(''Puffinus auricularis'') was probably extirpated in 1988 due to the feral pigs' depredations on the young and nesting birds.

Plants

Endemic plant taxa of Clarión are: * ''Aristida tenuifolia'' * ''Ipomoea halierca'' * ''Physalis clarionensis'' ''Brickellia peninsularis'' var. ''amphithalassa''''Bulbostylis nesiotica'', ''Cheilanthes peninsularis'' var. ''insularis'', ''Cyperus duripes'', ''Euphorbia anthonyi'', ''Nicotiana stocktonii'', ''Perityle socorrosensis'', ''Spermacoce nesiotica'' and ''Zapoteca formosa'' ssp. ''rosei'' are Revillagigedo endemics which Clarión shares with either San Benedicto or Socorro. Whether ''Teucrium townsendii'' var. ''townsendii'' is the same plant as on San Benedicto is not conclusively determined. There has not been recent dedicated research on the impact the sheep and rabbits had on the local

flora Flora is all the plant life present in a particular region or time, generally the naturally occurring (indigenous (ecology), indigenous) native plant, native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' ...

. While no plants seem to have gone extinct on the other Revillagigedo Islands, Clarión is one most heavily affected by introduced herbivores.

Notes

References

External links

Scuba Diving at Clarion Island
{{Authority control * Volcanoes of Colima Volcanoes of the Pacific Ocean Islands of Colima Pacific islands of Mexico Uninhabited islands of Mexico