Socorro Island (Spanish: Isla Socorro) is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying 600 kilometres (370 mi) 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 132 km2 (51 sq mi). It is the largest of the four islands of the Revillagigedo Archipelago.
|Native name: |
Socorro Island, from satellite image
Location in Mexico
|Area||132 km2 (51 sq mi)|
|Length||16.5 km (10.25 mi)|
|Width||11.5 km (7.15 mi)|
|Highest elevation||1,150 m (3,770 ft)|
|Highest point||Mount (Cerro) Evermann|
|Pop. density||0.34 /km2 (0.88 /sq mi)|
The island rises abruptly from the sea to 1,050 meters (3,440 feet) in elevation at its summit. Socorro Island is a shield volcano.
The island is part of the northern Mathematicians Ridge, a mid-ocean ridge that became largely inactive 3.5 million years ago when activity moved to the East Pacific Rise. All four islands along with the many seamounts on the ridge are post-abandonment alkaline volcanoes. Socorro Island is unusual in that it is the only dominantly silicic peralkaline volcanic island in the Pacific Ocean.
It most recently erupted in late January-early February, 1993, which was a submarine flank eruption off the coast from Punta Tosca. An earlier eruption was on May 21, 1951; earlier eruptions probably occurred in 1905, 1896 and 1848. The initial volcanic event probably occurred in 3090 BC +/- 500 years. Mount Evermann (Spanish: Cerro Evermann) is the name given to the summit dome complex, in honor of ichthyologist Barton Warren Evermann. The island's surface is broken by furrows, small craters, and numerous ravines, and covered in lava domes, lava flows and cinder cones.
There is a naval station, established in 1957, with a population of 250 (staff and families), living in a village with a church, that stands on the western side of Bahia Vargas Lozano, a small cove with a rocky beach, about 800 meters east of Cabo Regla, the southernmost point of the island. The station is served by a dock, a local helipad and Isla Socorro airport, located six kilometers to the north. There is a fresh water spring about 5 km northwest of Cabo Regla, at the shoreline of Ensenada Grayson (or Caleta Grayson), an inlet. This is brackish and sometimes covered by the sea at high tide. Apart from some temporary pools and maybe one that is more permanent, a small freshwater seep exists most of the time some 45 meters (49 yards) inland at Bahia Lucio Gallardo Pavon (Binner's Cove), 800 meters NW of the naval station.
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 19 December 1533 and named it Santo Tomás. In 1542, Ruy López de Villalobos, while exploring new routes across the Pacific, rediscovered Inocentes and renamed it Isla Anublada ("Cloudy Island") due to the clouds frequently forming on the northern slopes of Mount Evermann, and again in 1608, Martín Yañez de Armida, in charge of another expedition, visited Santo Tomás and changed its name to Isla Socorro after Our Lady of Perpetual Help (Virgen del Perpetuo Socorro).
At the beginning of the twentieth century, Barton Warren Evermann, director of the California Academy of Sciences in San Francisco promoted the scientific exploration of the island. The most comprehensive biological collections were obtained at this time. The volcano on Socorro was renamed in his honor.
Archie Smith, an American laborer from San Diego, was abandoned on the island for one month in 1929 before being rescued by a passing fishing boat.
In September 1997, the island was struck by Hurricane Linda, one of the strongest hurricanes ever recorded.
The lowlands of Socorro – except on the northern, more humid side – are covered with thick shrubland, consisting mainly of endemic Croton masonii and a cactus, probably Engelmann's prickly pear (Opuntia engelmannii). Above 650 metres (2,130 ft) and on the northern side, a richer vegetation occurs. This includes small trees such as Ficus cotinifolia, black cherry (Prunus serotina[note 1]), and the endemic Guettarda insularis, which bear epiphytic orchids (Epidendrum nitens, E. rigidum and the endemic Pleurothallis unguicallosa).
The native land fauna is depauperate, with birds predominating and mammals absent. There is one endemic species of iguanid lizard (Urosaurus auriculatus) and the land crab Johngarthia oceanica which also occurs on Clipperton Island.
Sheep, cats and rodents were introduced to the island by human activity; more recently, the locust Schistocerca piceifrons has also established itself on the island. Unlike the mammals on Guadalupe Island or Clarión, their impact on the local flora was minor, but cat predation has had a drastic effect since the mid-1970s due to the fauna's island tameness, and the locusts that swarm twice a year seriously damage vegetation during that time. There have been no recorded extinctions of plants on Socorro; several birds have been drastically affected by cat predation however, and one taxon, the Socorro dove, has gone extinct in the wild.
Socorro is an important breeding location for several seabirds, many of which have here one of their north(east)ernmost breeding colonies. The present status of these birds is not well known, and they presumably have suffered from cat predation. In 1953, the following taxa were present:
Non-endemic landbirds and shorebirds occur mostly as vagrants or use the island as a stopover during migration; the northern mockingbird became established in the late 20th century. Among those that are recorded not infrequently are great blue heron, Hudsonian curlew, spotted sandpiper and wandering tattler. Unlike the situation on smaller and more isolated Clarión, wind-blown or vagrant birds seem to constititute the bulk of the recorded species, including brown pelican, osprey, peregrine falcon, semipalmated plover, willet, sanderling, belted kingfisher and buff-bellied pipit. It may be that this puzzling observation is due to the presence of the red-tailed hawks and cats, which has at least made the local Urosaurus more wary than its relative on Clarión, and might deter passing birds from stopping on Socorro.
Being the largest of the Revillagigedo Islands and closer to mainland than Clarion, Socorro sports a rich array of endemic taxa, mainly plants and landbirds as well as lizards. Some are threatened due to the presence of feral cats.
Brickellia peninsularis var. amphithalassa, Cheilanthes peninsularis var. insularis, Nicotiana stocktonii, Spermacoce nesiotica and Zapoteca formosa ssp. rosei are near-endemics, being restricted to Socorro and Clarión. Whether Teucrium townsendii ssp. affine is the same plant as those on San Benedicto is not conclusively determined.
Socorro Island is a popular scuba diving destination known for underwater encounters with dolphins, sharks, manta rays and other pelagic animals. Since there is no public airport on the island, divers visit here on live-aboard dive vessels. The most popular months are between November and May when the weather and seas are calmer. November to December are popular months to visit for a good chance to dive with whale sharks.
The 1975 Pacific hurricane season officially started May 15, 1975, in the eastern Pacific, and June 1, 1975, in the central Pacific, and lasted until November 30, 1975. These dates conventionally delimit the period of each year when most tropical cyclones form in the northeast Pacific Ocean.The 1975 Pacific hurricane season was near average, with 17 tropical storms forming. Of these, 9 became hurricanes, and 4 became major hurricanes by reaching Category 3 or higher on the Saffir-Simpson Hurricane Scale. The only notable storms are Hurricane Olivia, which killed 30 people, caused $30 million (1975 USD) in damage, and left thousands homeless when it made landfall in October; and an unnamed hurricane that developed at very high latitude, but had no effect on land. Hurricane Denise was the strongest storm of the year. Hurricanes Lily and Katrina passed close to Socorro Island and Tropical Storm Eleanor made landfall in Mexico. Hurricane Agatha sank a ship.Blue mackerel
The blue mackerel (Scomber australasicus), also called Japanese mackerel, Pacific mackerel, slimy mackerel or spotted chub mackerel, is a fish of the family Scombridae, found in tropical and subtropical waters of the Pacific Ocean from Japan south to Australia and New Zealand, in the eastern Pacific (Hawaii and Socorro Island, Mexico), and the Indo-West Pacific: the Red Sea, the Persian Gulf, the Gulf of Oman and the Gulf of Aden, in surface waters down to 200 m (660 ft). In Japanese, it is known as goma saba (胡麻鯖 sesame mackerel). It typically reaches 30 cm (12 in) in length and 1.4 kg (3.1 lb) in weight.Clarion Island
Isla Clarión, formerly called Santa Rosa, is the second largest, westernmost and most remote of the Revillagigedo Islands (part of Mexico, specifically the state of Colima), located 314 kilometres (195 mi) west of Socorro Island and over 700 kilometres (430 mi) from the Mexican mainland.
It has an area of 19.80 square kilometres (7.64 sq mi) and three prominent peaks. The westernmost and tallest peak, Monte Gallegos, is 335 metres (1,099 ft) high. The central peak is called Monte de la Marina, 280 metres (920 ft), and the eastern peak Pico de la Tienda 292 metres (958 ft). The coasts are backed by perpendicular cliffs, 24 to 183 metres (79 to 600 ft) 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 manned by 9 men.
Two small and at least temporarily brackish pools are the only source of fresh water; even these may dry up in summers with little rain.Erigeron socorrensis
Erigeron socorrensis is a Mexican species of flowering plant in the daisy family known by the common name Socorro Island fleabane. It has been found only on Socorro Island in Mexico, part of the State of Colima. This is a small, volcanic island about 390 kilometres (240 miles) south-southwest of the southern end of the Peninsula of Baja California, the largest of the Revillagigedo Islands.
Erigeron socorrensis is a shrub up to 120 cm (3.9 ft) tall, with a large woody caudex. It has narrowly oblanceolate leaves up to 8 cm (3 in) long. One plant can produce several groups of small flower heads, each group at the end of a long, thin stalk. Each head is 3–4 mm (0.12–0.16 in) long, with several white ray florets surrounding several yellow disc florets.Guamblin Island
Guamblin Island, also known as Socorro Island, Nuestra Señora del Socorro or Huamblin, is a Chilean island. It is part of the Chonos Archipelago, although it is some 25 km distant from the other islands of the archipelago, far out in the Pacific Ocean.
The island is a National Park, and listed as an Important Bird Area. It is a breeding ground of the sooty shearwater.Hurricane Adrian (1999)
Hurricane Adrian caused generally minor damage along its path in mid-June 1999, though it left six people dead in its wake. The first tropical cyclone and first hurricane of the well below-average 1999 Pacific hurricane season, Adrian formed out of a broad area of low pressure south of the Gulf of Tehuantepec that persisted for several days. The disturbance was intertwined with a tropical wave that departed the western coast of Africa on June 5, and both features congealed into a tropical depression by early on June 18. The nascent cyclone paralleled the southwestern coastline of Mexico, intensifying into Tropical Storm Adrian shortly after formation and attaining its peak as a Category 2 hurricane with winds of 100 mph (160 km/h) late on July 20. Though remaining offshore, it resulted in minor flooding and insignificant damage to infrastructure. Four people were killed by a large wave along the coastline of Chiapas, and an additional two people were killed in Durango while trying to cross a flooded river in a pick-up truck; a five-year-old girl accompanying the men went missing. Wind shear and cooler ocean temperatures weakened Adrian as it produced minor damage on Socorro Island, and the system ultimately degenerated into a remnant low late on June 22.Hurricane Bonny
The name Bonny has been used for four tropical cyclones in the Eastern Pacific Ocean. "Bonny" is not to be confused with "Bonnie", which is used in the Atlantic Ocean.
Tropical Storm Bonny (1960), formed southwest of Mexico and moved northwestward; did not make landfall
Tropical Storm Bonny (1968), winds of 60 mph (97 km/h) were measured on Socorro Island
Tropical Storm Bonny (1972), never came near land and caused no known impact
Hurricane Bonny (1976), never threatened landHurricane Linda (1997)
Hurricane Linda was the second-strongest eastern Pacific hurricane on record. Forming from a tropical wave on September 9, 1997, Linda steadily intensified and reached hurricane status within 36 hours of developing. The storm rapidly intensified, reaching sustained winds of 185 mph (295 km/h) and an estimated central pressure of 902 millibars (26.6 inHg); both were records for the eastern Pacific until Hurricane Patricia surpassed them in 2015. The hurricane was briefly forecast to move toward southern California, but instead, it turned out to sea and lost its status as a tropical cyclone on September 17, before dissipating on September 21. Linda was the fifteenth tropical cyclone, thirteenth named storm, seventh hurricane, and fifth major hurricane of the 1997 Pacific hurricane season.
While near peak intensity, Hurricane Linda passed near Socorro Island, where it damaged meteorological instruments. The hurricane produced high waves along the southwestern Mexican coastline, forcing the closure of five ports. If Linda had made landfall on southern California as predicted, it would have been the strongest storm to do so since a storm in 1939. Though it did not hit the state, the hurricane produced light to moderate rainfall across the region, causing mudslides and flooding in the San Gorgonio Wilderness; two houses were destroyed and 77 others were damaged, and damage totaled US$3.2 million (as of 1997; value $5.2 million as of 2018).Hurricane Norman (1978)
Hurricane Norman was the most recent tropical system to make landfall in California. The 14th named storm, 11th hurricane, and 6th major hurricane of the 1978 Pacific hurricane season, Norman evolved from a tropical disturbance noted 400 mi (640 km; 350 nmi) southeast of Acapulco on the afternoon of August 29, 1978. The system moved westward and developed into a tropical depression on August 30. Modest strengthening ensued, and the cyclone became a tropical storm that evening and a hurricane on the evening of August 31 as it turned to the west-northwest. Late on the night of September 1, Norman became a major hurricane with an eye 40 miles (64 km; 35 nmi) wide, and a nearby ship reported seas of 41 ft (12 m). The center grazed the northeast side of Socorro Island on the afternoon of September 2. Moving over cooler waters west of Baja California, the cyclone slowly weakened. By early on September 4, moisture from the hurricane spread north into California initiating rains in the Golden State. A developing trough to its west caused the initial influx of moisture and Norman's turn to the north as a weakening tropical storm. Eventually turning north-northeast towards southern California, the cyclone did eventually turn north-northeast towards southern California, and the cyclone weakened to a tropical depression as it passed the 30th parallel. Hurricane Norman made landfall in California on September 5, as a minimal tropical depression. The tropical cyclone became a remnant low shortly after California landfall, and the final advisory was issued at 00:00 GMT, on September 6. Over 7.01 in (178 mm) of rain occurred in the Sierra Nevada range. Rare snowfall was also reported.Johngarthia planata
Johngarthia planata, sometimes known as the Clipperton crab, is a bright orange species of land crab that lives on Clipperton Island in the eastern Pacific; on Malpelo Island, west of Colombia; and on Socorro Island in the Revillagigedo Islands off Mexico, 900 km north of Clipperton. It is omnivorous and feeds on seaweed (algae), vegetation and sometimes carrion.
The introduction of pigs on Clipperton Island by guano miners in the 1890s reduced the crab population: this in turn allowed grassland to gradually cover about 80 percent of the land surface. The elimination of these pigs in 1958 — as the result of a personal project by Kenneth E. Stager — has caused most of this vegetation to disappear, resulting in the return of millions of J. planata. A 2005 report by the NOAA's Southwest Fisheries Science Center in La Jolla, California, USA indicates that the increased rat presence has led to a decline in the crab population, causing a corresponding increase in both vegetation and coconut palms. This report urgently recommended eradication of rats so that vegetation might be reduced and the island might return to its "pre-human" state.Socorro dove
The Socorro dove (Zenaida graysoni) 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. A reintroduction program is in the early stages of preparation.It is a close relative of the mourning and eared doves, particularly the former and was at one time considered a subspecies. In captivity, it hybridizes with the former and almost all privately owned birds as well as several of the captive breeding programs are known or strongly suspected to be hybrids. These are excluded from the reintroduction program as there is evidence of unique adaptations in the Socorro species. The scientific name commemorates Zénaïde Laetitia Julie Bonaparte and the American ornithologist and artist Andrew Jackson Grayson.Socorro parakeet
The Socorro parakeet (Psittacara brevipes) is a species of parrot endemic to Socorro Island in the Revillagigedo Islands, Mexico. Some ornithologists consider it to be a subspecies of the green parakeet (Psittacara holochlorus). Its natural habitat is subtropical or tropical moist lowland forest. It is threatened by habitat loss due to feral sheep and predation by feral cats. The Socorro parakeet's mating season starts in November.Sorghastrum
Sorghastrum is a genus of grasses, native to Africa and the Americas.Members of the genus are commonly known as Indiangrass.
SelectedSorghastrum balansae (Hack.) Dávila - Paraguay
Sorghastrum brunneum Swallen - Mexico, Guatemala, Honduras
Sorghastrum chaseae Swallen - Mato Grosso, Paraíba
Sorghastrum contractum (Hack.) M.Kuhlm. & Kuhn - Brazil
Sorghastrum crassum Renvoize - Bolivia
Sorghastrum elliottii (C.Mohr) Nash – Slender Indiangrass - southeastern + south-central USA (Texas to Virginia)
Sorghastrum fuscescens (Pilg.) Clayton - Tanzania, Zambia, Malawi
Sorghastrum incompletum (J.Presl) Nash - Latin America from Mexico to Bolivia; Africa from Senegal to Zimbabwe
Sorghastrum minarum (Nees) Hitchc. - Bolivia, Brazil, Paraguay, Argentina
Sorghastrum nudipes Nash - Chihuahua, Durango, Sonora, Limpopo, Botswana, Namibia, Zimbabwe, Zambia, Mozambique, Malawi, Angola
Sorghastrum nutans (L.) Nash – Yellow Indiangrass - Canada, USA, Mexico, Honduras
Sorghastrum pellitum (Hack.) Parodi - Paraguay, Brazil, Argentina, Uruguay
Sorghastrum pogonostachyum (Stapf) Clayton - Tanzania, Angola, Zambia, Malawi
Sorghastrum pohlianum Dávila, L.I.Cabrera & R.Lira - Socorro Island in Colima
Sorghastrum scaberrimum (Nees) Herter - Brazil
Sorghastrum secundum (Elliott) Nash – Lopsided Indiangrass - southeastern USA; Bahamas
Sorghastrum setosum (Griseb.) Hitchc. – Sandysoil Indiangrass - Latin America + West Indies from Veracruz to Uruguay
Sorghastrum stipoides (Kunth) Nash – Needle Indiangrass - tropical + southern Africa; naturalized in Latin America
Sorghastrum tisserantii Clayton - Central African Rep
Sorghastrum viride Swallen - Paraguay, Brazil, Argentina, UruguaySpotted towhee
The spotted towhee (Pipilo maculatus) is a large New World sparrow. The taxonomy of the towhees has been debated in recent decades, and until 1995 this bird and the eastern towhee were considered a single species, the rufous-sided towhee. Literature before 1995 referred to the spotted towhee as a rufous-sided towhee that resides in the western United States. An archaic name for the spotted towhee is the Oregon towhee (Pipilo maculatus oregonus). The call may be harsher and more varied than for the eastern towhee.
The form that breeds on Socorro Island is much smaller than other rufous-sided towhees, and has gray upperparts. It is sometimes split as the Socorro towhee (Pipilo socorroensis).Timeline of the 2010 Pacific hurricane season
The 2010 Pacific hurricane season was one of the least active seasons on record, featuring the fewest named storms since 1977. The season officially started on May 15 in the eastern Pacific—east of 140°W—and on June 1 in the central Pacific—between the International Date Line and 140°W—and lasted until November 30. These dates typically cover the period of each year when most tropical cyclones form in the eastern Pacific basin. The season's first storm, Tropical Storm Agatha, developed on May 29; the season's final storm, Tropical Storm Omeka, degenerated on December 21.
The season began with record-breaking activity with four named storms, including two major hurricanes, developing by the end of June. Accumulated cyclone energy (ACE) values exceeded 300 percent of the average for the month of June. Activity abruptly diminished thereafter, with July, August, and September seeing record low storm development. The Eastern Pacific season proper ended with Tropical Storm Georgette's dissipation on September 23, a month before the climatological mean. The year's final cyclone, Omeka, developed in the off-season on December 18, marking a record-late formation date in the satellite-era. Although there were relatively few storms, the season proved exceptionally deadly and destructive. Torrential rains associated with Agatha and Eleven-E killed well over 200 people in Central America and Mexico and left more than $1.5 billion in damage.Four time zones are utilized in the basin: Central for storms east of 106°W, Mountain between 114.9°W and 106°W, Pacific between 140°W and 115°W, and Hawaii–Aleutian for storms between the International Date Line and 140°W. However, for convenience, all information is listed by Coordinated Universal Time (UTC) first with the respective local time included in parentheses. This timeline includes information that was not operationally released, meaning that data from post-storm reviews by the National Hurricane Center, such as the subtropical phase of Omeka, is included. This timeline documents tropical cyclone formations, strengthening, weakening, landfalls, extratropical transitions, and dissipations during the season.Tropical Storm Dalila (2007)
Tropical Storm Dalila caused flooding in western Mexico in late July 2007. The seventh tropical cyclone and the fourth named storm of the 2007 Pacific hurricane season, Dalila developed from a tropical wave located well southwest of Mexico on July 22. Initially, northeasterly shear caused the depression to remain disorganized, though by early on July 24, it was upgraded to Tropical Storm Dalila. During the next twenty-four hours, Dalila strengthened slightly further while tracking steadily northwestward, attaining peak winds of 60 mph (95 km/h) early on the following day. Shortly thereafter, Dalila either crossed or moved very close to Socorro Island on July 25. Due to decreasing sea surface temperatures, the storm slowly began to weaken, after curving west-northwestward. Early on July 27, Dalila was downgraded to a tropical depression, several hours before degenerating into a remnant low pressure area.
Despite its close passage to Socorro Island near peak intensity, no impact was reported. On the mainland of Mexico, the outer bands of Dalila dropped heavy rainfall, especially in Baja California Sur, Jalisco, with more than 16 inches (410 mm) of precipitation in some areas. The worst flooding occurred in Jalisco, where streets were inundated with more than 6 feet (1.8 m) of water, causing many car accidents. Additionally, 50 homes were destroyed, leaving approximately 200 people homeless. Eleven fatalities were confirmed, all of them occurred in Jalisco, most of which from drowning. Portions of Baja California Sur also experienced heavy rains from Dalila and its remnants, though no flooding was reported.Tropical Storm Hazel (1965)
Tropical Storm Hazel was a weak East Pacific tropical cyclone that caused heavy damage in Mexico. The costliest storm of the 1965 Pacific hurricane season, it formed from a northward-moving disturbance that originated southeast of Socorro Island. After reaching tropical storm strength on the Saffir–Simpson Hurricane Scale, the cyclone turned to the east-northeast. The storm made landfall near Mazatlán on September 26 and quickly transitioned an extratropical cyclone. Although fairly weak, the system was responsible for causing heavy damage to the Mexican economy. Flooding in Mazatlán washed out many houses and submerged others in muddy water. At least six people died with damages totaling $10 million (1965 USD) and possibly higher. The name Hazel was retired following this storm, likely due to the Atlantic storm of the same name.Tropical Storm Lowell (2008)
Tropical Storm Lowell was a moderate tropical storm that developed during the 2008 Pacific hurricane season. The fourteenth tropical cyclone and thirteen named storm of the season, Lowell formed out of a western side of a trough on September 6. It quickly intensified into Tropical Storm Lowell, peaking as a moderate tropical storm. It pass directly over Socorro Island and began a weakening trend. It weakened into depression before landfall in Baja California Sur and dissipated before striking Sonora. It later joined with a frontal boundary and Hurricane Ike which caused severe damage as far inland as Chicago. In all, the storm had caused 6 deaths and $15.5 million damage.
Eastern Pacific Islands