Guadalupe Island
From Wikipedia, the free encyclopedia
- For the French Caribbean island, see Guadeloupe.
Guadalupe Island, or Isla Guadalupe, () is a volcanic island located 241 kilometers (150 miles) off the west coast of Mexico's Baja California peninsula and some 400 kilometers (250 miles) southwest of the border city of Tijuana in Baja California state, in the Pacific Ocean. The two other Mexican island groups in the Pacific Ocean that are not on the continental shelf are Revillagigedo Islands and Rocas Alijos.
Contents |
[edit] Administration
Guadalupe Island is part of Ensenada municipality of the Mexican state of Baja California, and its postal code is 22997.
[edit] Population
A small population of abalone and lobster fishermen lived near a cove at Campamento Este (East Camp) on the eastern shore, but the camp is abandoned now. At the southern tip, on Melpómene Cove, there is a weather station. The site is called Campamento Sur (South Camp). There is a small airstrip near the center of the island.
[edit] Environment
Guadalupe shares the California chaparral and woodlands ecoregion with the Channel Islands of California in the United States, but the island has been practically denuded of all plants higher than a few centimeters due to tens of thousands of goats. Originally brought there in the early 19th century by primarily Russian whalers and sealers for provisions when stopping over, the population eventually eliminated most vegetation; the number of goats declined to a few thousand. Eradication of the goats was long envisioned, but logistical difficulties such as island size and lack of suitable spots for landing and encamping hunters and material prevented this. As of June 2005, after many years of false starts, the Mexican government has almost completed a round-up and evacuation of the remaining goat population; it has been designated a biosphere reserve. The island had been a nature conservancy area since August 16, 1928, making it one of the oldest reserves in Mexico.
Of the tree species (a palm, a cypress, an oak, and a pine), there were only old individuals left. As the goats ate any seedlings that managed to germinate, no regeneration of trees was possible. Water, formerly plentiful as the common fogs condensed in the forests of the northern end of the island, today only occurs in a few scattered pools and springs. Because the springs were a critical emergency water supply for the human inhabitants, protective measures including goat fences were installed beginning in 2000, allowing new seedlings of many species to survive for the first time in 150 years.
[edit] Climate
The islands two major climate zones: a very arid, semi-hot climate between 0 and 800 meters elevation, with mean annual temperature in between 18-22°C, and very arid, temperate climate above 800 meters elevation with temperatures over 22°C in the hottest month of the year.
Most precipitation occurs over the winter months with strong influence of northwestern winds and cyclones.
[edit] Wildlife
Many unique island or marine species that reside on or near Guadalupe also frequent the Channel Islands, and vice-versa. Guadalupe is considered one of the best spots in the world for sightings of the Great White Shark, possibly because of its large population of pinnipeds. A joint team from the USA and Mexico (U.C Davis and CICIMAR) are working in tandem with eco-tour operators Horizon Charters, Islander Charters and Shark Diver to tag and study these sharks. It was the last refuge for the Northern elephant seal (Mirounga angustirostris) and the Guadalupe fur seal (Arctocephalus townsendi). The island has been a pinniped sanctuary since 1975.
- Guadalupe Fur Seal (Arctocephalus townsendi)
- Guadalupe Junco (Junco insularis)
- Guadalupe Cypress (Cupressus guadalupensis)
- Guadalupe Island Monterey Pine (Pinus radiata var. binata)
Numerous species and subspecies have gone extinct due to the habitat destruction by the goats, which in turn rendered the endemic fauna vulnerable to predation by introduced cats and to adverse weather by depriving them of shelter. There have been 5-6 extinctions of birds alone:
- Guadalupe Storm Petrel (Oceanodroma macrodactyla), 1911
- Guadalupe Flicker (Colaptes cafer rufipileus), 1906 - the island was later recolonized by individuals of the nominate subspecies
- Guadalupe Bewick's Wren (Thyromanes bewickii brevicauda), 1903
- Guadalupe Spotted Towhee (Pipilo maculatus consobrinus), 1897
The Guadalupe Ruby-crowned Kinglet (Regulus calendula obscurus) is close to extinction, if it indeed still exists. It was not observed in 2000 despite thorough searches.
The Guadalupe Caracara (Polyborus lutosus) was intentionally made extinct by humans around 1901, ironically because it occasionally preyed on young goats.
[edit] Geography
Guadalupe has a rugged landscape. It consists of two ancient overlapping shield volcanoes, of which the northern and higher volcano (Mount Augusta) is the younger. The island measures 35 km north-south and up to 9.5 km east-west, with a total area of 253.8 km² (98 square miles). It features a chain of high volcanic mountain ridges which rises to a height of 1298 meters (4257 feet) at its northern end (Mount Augusta). The southern part of the island is barren, but there are fertile valleys and trees in the northern part. The coast generally consists of rocky bluffs with detached rocks fronting some of them. Two high and prominet islets are within 3 km of the southwestern end of the island, separated from one another by a gap called Tuna Alley:
- Islote Afuera (Outer Islet, also Islote Zapato), the most distant, steep with almost vertical walls above and below water
- Islote Adentro (Inner Islet, also El Toro), with two smaller islets nearby:
- Church Rock
- Roca del Skip
Elsewhere, the other islets are very small and close to the shore, all less than one kilometer away, for example:
- Islote Negro to the southwest
- Steamboat Rock to the west
- Roca Elefante to the northwest
[edit] External links
- Great White shark research program update
- Sailing directions, with geographical information
- Photographs of Isla Guadalupe
- Expedition 2000 to Isla Guadalupe—A Binational Multidisciplinary Expedition
- Guadalupe Island, another paradise that is lost - pre-removal profile of island
- Seacology Guadalupe Island Project - updates on ecosystem
- Guadalupe Island Restoration Project - Island Conservation
