Brahea edulis
Encyclopedia
Brahea edulis is a palm
native and almost endemic
to Guadalupe Island
, Mexico
; a few stands have been planted elsewhere. This is a fan palm
which grows 4.5–13 metres tall. It grows between 400 and 1000 meters above mean sea level
(ASL).
The entire native population consists of old trees with little successful recruitment for 150 years or so. Until recently, Guadalupe Island supported a large goat population (estimated at 100,000 in 1870, and 5,000 in 2000). The presence of these goats prevented regrowth of the native trees, including B. edulis, and as a consequence, the ecosystem was drastically altered: the once verdant island turned an almost barren rock, with weeds replacing the former forests. Below 800–900 m ASL the palm is essentially the only remaining tree, occurring in a major subpopulation and scattered groups in sheltered locations. Above that, there used to be a band of mixed woodland where the palm was accompanied by Island Oak
and Guadalupe Pine. This habitat
has now all but disappeared due to the other trees becoming pushed back into higher regions.
The species was probably declining slowly since the mid-19th century. Its range might even have expanded a bit until the mid-20th century however; part of it was shared with other trees as noted above; especially the pine is a towering species that presumably grew in many sites now occupied by the palm. In addition, a forest of Guadalupe Cypress and California Juniper shrubland existed in the palm's present range; the cypress forest was eventually destroyed by the goats and the juniper is nowadays completely absent fron the island.
Although endangered in the wild, B. edulis is cultivated, especially in California
. In 2001, it was started to fence in patches of habitat on Guadalupe, and the long-envisioned removal of goats was effectively complete by 2005. Some hundreds of Guadalupe Palms remain on their island home today. As regrowth presumably was hindered by the goats eating the saplings rather than the trees having all become old and sterile, it is likely that the palm will eventually recover. That it was best able of all Guadalupe tree species to withstand the hordes of goats is evidenced by its present distribution; the other trees – if they survive at all – are limited to higher and less accessible areas. Nonetheless, the species is precariously rare and the IUCN considers it Endangered (EN C1).
Arecaceae
Arecaceae or Palmae , are a family of flowering plants, the only family in the monocot order Arecales. There are roughly 202 currently known genera with around 2600 species, most of which are restricted to tropical, subtropical, and warm temperate climates...
native and almost endemic
Endemic (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...
to 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...
, 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...
; a few stands have been planted elsewhere. This is a fan palm
Fan palm
Fan palm as a descriptive term can refer to any of several different kinds of palms in various genera with leaves that are palmately compound...
which grows 4.5–13 metres tall. It grows between 400 and 1000 meters above mean sea level
Above mean sea level
The term above mean sea level refers to the elevation or altitude of any object, relative to the average sea level datum. AMSL is used extensively in radio by engineers to determine the coverage area a station will be able to reach...
(ASL).
The entire native population consists of old trees with little successful recruitment for 150 years or so. Until recently, Guadalupe Island supported a large goat population (estimated at 100,000 in 1870, and 5,000 in 2000). The presence of these goats prevented regrowth of the native trees, including B. edulis, and as a consequence, the ecosystem was drastically altered: the once verdant island turned an almost barren rock, with weeds replacing the former forests. Below 800–900 m ASL the palm is essentially the only remaining tree, occurring in a major subpopulation and scattered groups in sheltered locations. Above that, there used to be a band of mixed woodland where the palm was accompanied by Island Oak
Island Oak
Quercus tomentella, the Island Oak, also the Island Live Oak or Channel Islands Oak, is an oak in the section Protobalanus.-Distribution:...
and Guadalupe Pine. This habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
has now all but disappeared due to the other trees becoming pushed back into higher regions.
The species was probably declining slowly since the mid-19th century. Its range might even have expanded a bit until the mid-20th century however; part of it was shared with other trees as noted above; especially the pine is a towering species that presumably grew in many sites now occupied by the palm. In addition, a forest of Guadalupe Cypress and California Juniper shrubland existed in the palm's present range; the cypress forest was eventually destroyed by the goats and the juniper is nowadays completely absent fron the island.
Although endangered in the wild, B. edulis is cultivated, especially in 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 2001, it was started to fence in patches of habitat on Guadalupe, and the long-envisioned removal of goats was effectively complete by 2005. Some hundreds of Guadalupe Palms remain on their island home today. As regrowth presumably was hindered by the goats eating the saplings rather than the trees having all become old and sterile, it is likely that the palm will eventually recover. That it was best able of all Guadalupe tree species to withstand the hordes of goats is evidenced by its present distribution; the other trees – if they survive at all – are limited to higher and less accessible areas. Nonetheless, the species is precariously rare and the IUCN considers it Endangered (EN C1).