Geoffroy's Spider Monkey

Taxobox
name = Geoffroy's Spider MonkeyMSW3 Groves|pages=150–151|id=12100399]


image_caption = "A. g. ornatus" in southern Costa Rica
status = EN
status_system = iucn3.1
status_ref = IUCN2008|assessors=Cuarón, A.D., Morales, A., Shedden, A., Rodriguez-Luna, E. & de Grammont, P.C.|year=2008|id=2279|title=Ateles geoffroyi|downloaded=7 October 2008 Database entry includes justification for why this species is endangered]
regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Primates
familia = Atelidae
genus = "Ateles"
species = "A. geoffroyi"
binomial = "Ateles geoffroyi"
binomial_authority = Kuhl, 1820
synonyms =
*"frontatus" (Gray, 1842)
*"melanochir" (Desmarest, 1820)
*"trianguligera" (Weinland, 1862)

Geoffroy's Spider Monkey, "Ateles geoffroyi", also known as Black-handed Spider Monkey, is a species of spider monkey, a type of New World monkey, from Central America.

Description

Geoffroy's Spider Monkey is one of the largest New World monkeys. Its length measures between convert|30|and|63|cm|in|lk=on|abbr=on and it weighs between convert|6|and|9|kg|lb|lk=on|abbr=on.cite book|title=The Pictorial Guide to the Living Primates|author=Rowe, N.|year=1996|page=114|isbn=0-9648825-0-7] cite book|title=Neotropical Rainforest Mammals|edition=Second Edition|author=Emmons, L.|page=143–144|year=1997|isbn=0-226-20721-8] The prehensile tail is longer than the body at between convert|63|and|85|cm|in|lk=on|abbr=on. Males are slightly larger than females.cite book|title=Primates in Perspective|chapter=The Atelines|author=Di Fiore, A. & Campbell C.|editor = Campbell, C., Fuentes, A., MacKinnon, K., Panger, M., & Bearder, S.|year=2007|page=624|isbn=978-0-19-517133-4]

The body color varies by population between buff and black. Usually the forearms, hands, lower legs and feet are dark or black. The face usually has a pale mask around the eyes and muzzle.

The arms and legs are long and slim.cite book|title=Watching Wildlife in Central America|author=Hunter, L. and Andrew, D.|year=2002|page=151|isbn=1-86450-034-4] Arms are about 25% longer than the legs.cite book|title=The Natural History of Costa Rican Mammals|author=Wainwright, M.|year=2002|page=146–149|isbn=0-9705678-1-2] There is only a vestigal thumb, but the fingers are long and strong, making the hands hook-like. The long arms and hook-like hands allow Geoffroy's Spider Monkey to brachiate, that is, swing from its arms beneath the tree branches.

The prehensile tail is very strong and has a palm-like pad at the end. The tail acts as an extra limb, and is used for locomotion as well as to pick fruits and to scoop water from holes in trees. Geoffroy's Spider Monkey can support its weight suspended by its tail and often does so when feeding.cite book|title=Primates of Columbia|author=Defler, T.|page=339–347|year=2004|isbn=1-881-17383-6] [cite web|title=Primate Abstract Spider Monkey|url=http://www.wellingtonzoo.com/animals/animals/primates/spider-monkey.html|accessdate=2008-08-29]

The clitoris of female Geoffroy's Spider Monkeys is large and protrudes, looking like a penis. As a result, females are sometimes mistaken for males by human observers.

Distribution and habitat

The range of Geoffroy's Spider Monkey extends over much of Central America, and probably into Colombia.cite book|title=New Perspectives in the Study of Mesoamerican Primates|chapter=Taxonomy and Distributions of Mesoamerican Primates|author=Rylands, A., Groves, C., Mittermeier, R., Cortes-Ortiz, L., and Hines, J.|year=2006|page=56–66|isbn=0-387-25854-X] Its range encompasses Panama, Costa Rica, Nicaragua, Guatemala, Honduras, El Salvador and Belize. The range also includes the south and much of the eastern portion of Mexico. The southernmost subspecies, the Hooded Spider Monkey, "Ateles geoffroyi grisescens", is also reported to occur in Colombia, but is most likely restricted to the portion of Colombia immediately abutting Panama.IUCN2007|assessors=Ryland, A. et al|year=2000|id=2287|title=Ateles geoffroyi "ssp." grisescens |downloaded=2008-08-30] In western Colombia and northeast Panama it is replaced by the Black-headed Spider Monkey, "A. fusciceps".

Geoffroy's Spider Monkey lives in various types of forest. This includes rainforests, semi-deciduous forests and mangrove forests. [cite web|title=BBC Black-Handed Spider Monkey|url=http://www.bbc.co.uk/nature/wildfacts/factfiles/310.shtml|accessdate=2008-08-29] Higher densities of Geoffroy's Spider Monkeys appear to be found in areas containing evergreen forest. [cite book | author = DeGama, H. and Fedigan, L. | editor = Estrada, A.; Garber, P.A.; Pavelka, M.S.M.; Luecke, L. | chapter = The Effects of Forest Fragment Age, Isolation, Size, Habitat Type, and Water Availability on Monkey Density in a Tropical Dry Forest | title = New Perspectives in the Study of Mesoamerican Primates| page = 165–186 | isbn=978-0-387-25854-6 | year = 2006]

Behavior

Geoffroy's Spider Monkeys are arboreal and diurnal, and mostly inhabit the upper portion of the forest. They are gregarious and live in large groups with an average group size of from 20 to 42 members, depending on the population.cite book|title=Primate Ecology and Social Structure Volume 2: New World Monkeys|edition=Revised First Edition|author=Sussman, R.|year=2003|page=138–142|isbn=0-536-74364-9] Geoffroy's Spider Monkeys live in fission–fusion societies in which the main group splits into smaller subgroups to forage during the day. Subgroups typically number two to six members, Sometimes the subgroups remain separate from the main group even through the night.

Geoffroy's Spider Monkeys forage over large tracts of forest in seacrh of food. Home ranges for groups can exceed convert|900|ha|acre|abbr=off|lk=on. Monkeys can range about convert|2000|m|ft|abbr=off|lk=on each day. Males tend to cover a larger day range than females and dominant individuals tend to have larger day ranges.

Geoffroy's Spider Monkey sometimes rubs a mixture of saliva and ground lime tree "Citrus aurantifolia" leaves on their fur. This is believed to act as an insect repellent.

In some locations, Geoffroy's Spider Monkeys interact with White-faced Monkeys. These interactions can include mutual grooming.cite book|title=Primates of Columbia|author=Defler, T.|page=234|year=2004|isbn=1-881-17383-6]

Maximum life span in the wild is unknown. In captivity, Geoffroy's Spider Monkeys can live to at least 33 years old.

Diet

Geoffroy's Spider Monkey primarily eats fruit, preferably ripe, fleshy fruit. Eating fruit occupies 70% to 80% of its feeding time. Leaves make up most of the rest of its diet. Young leaves are especially important to provide protein that can be lacking in fruit. Other elements of its diet include flowers, bark, insects and honey.

Predators

Large cats – jaguars and pumas – appear to be the only significant adult spider monkey predators, other than humans. [cite web|title=Predation of wild spider monkeys at La Macarena, Colombia|url=http://www.springerlink.com/content/k81437kp74307841/|author=Matsuda, I. & Izawa, K.|accessdate=2008-08-29] Eagles and large snakes are also potential predators.cite web |last = Cawthon Lang |first = KA |date = 2005-04-10 |title = Primate Factsheets: Black spider monkeyAteles paniscus |publisher = Wisconsin Primate Research Center (WPRC) |url = http://pin.primate.wisc.edu/factsheets/entry/black_spider_monkey/taxon |accessdate = 2008-08-29]

Vocal communication

Sounds produced by Geoffroy's Spider Monkey include barks, whinnies,squeals, squeaks and screams. Barks are typically alarm calls. Whinnies and screams are used as distress call, and are also made at dawn and at dusk. Each monkey makes a unique sound. This may allow monkeys to recognize each other through vocal communication alone.

Reproduction

Female Geoffroy's Spider Monkeys only bear young every two to four years Geoffroy's Spider Monkeys mate in a sitting position, both facing the same direction, with the male seated behind the female and his arms wrapped around her chest and legs wrapped around her waist. This embrace can last for between 8 and 22 minutes.

The gestational period is about 7.5 months, after which a single young is typically born. The young are dark in color until they begin taking on the adult coloration at the age of five months. They are carried on their mothers' chest for the first 1.5 to two months, at which point they can ride on her back. They nurse until they are about one year old, but begin eating solid foods and moving independently at about three months. Once they move independently, they still cannot always cross gaps in the canopy that adults can manage. As a result, an adult will stretch across the gap, forming a bridge that the young can cross.

Females become sexually mature at about four years; males at about five years. Upon reaching sexual maturity, females leave their natal group but males do not. As a result, the males in the groups are typically related while the females are not. This may help explain why male Geoffroy's Spider Monkeys form strong bonds.

Intelligence

Although it does not use tools, Geoffroy's Spider Monkey is regarded as an intelligent primate. A study performed in 2007 concluded that spider monkeys were the third most intelligent non-human primate, behind only orang-utans and chimpanzees, and ahead of gorillas and all other monkeys.cite web|title=Chimps Knocked Off Top of the IQ Tree|url=http://www.timesonline.co.uk/tol/news/uk/article1654998.ece|author=Leake, D. & Dobson, R.|date=April 15, 2007|year=2007|accessdate=2008-08-29]

Conservation

Geoffroy's Spider Monkey is listed as "Least Concern" by IUCN. However, they require large tracts of primary forest to survive, and so they are vulnerable to deforestation. They are sometimes also hunted by humans and captured as pets. Because of their low reproductive turnover, they cannot quickly replenish their numbers when impacted by these events. As a result, Geoffroy's Spider Monkey has disappeared from some areas where it was once common. Several subspecies are considered endangered or critically endangered.IUCN2007|assessors=Cuarón, A.D., de Grammont, P.C., Cortés-Ortiz, L. Wong, G. & Silva, J.C.S.|year=2003|id=2289|title=Ateles geoffroyi "ssp." ornatus|downloaded=2008-07-14] IUCN2007|assessors=Cuarón, A.D., de Grammont, P.C., Cortés-Ortiz, L. Wong, G. & Silva, J.C.S.|year=2003|id=39923|title=Ateles geoffroyi "ssp." vellerosus|downloaded=2008-08-31]

One area where Geoffroy's Spider Monkey was eliminated was Barro Colorado Island in Panama. Hunting had eliminated the native population there by 1912. However, in the mid-1960s an effort was made to reintroduce the species to Barro Colorado. At least 18 monkeys were reintroduced but only 5, 1 male and 4 females, survived the reintroduction. But this small group has thrived, and the island population had grown to 28 monkeys by 2003.cite book|title=New Perspectives in the Study of Mesoamerican Primates|chapter=Spider Monkey Population on Barro Colorado Island, Panama|author=Milton, K. & Hopkins, M.|year=2006|page=67–69|isbn=0-387-25854-X]

ubspecies

There are five recognized subspecies of this monkey:
* Yucatan Spider Monkey, "Ateles geoffroyi yucatanensis"
* Mexican Spider Monkey, "Ateles geoffroyi vellerosus"
* "Ateles geoffroyi geoffroyi"
* Ornate Spider Monkey, "Ateles geoffroyi ornatus"
* Hooded Spider Monkey, "Ateles geoffroyi grisescens"

The Brown Spider Monkey, "Ateles fusciceps" was formerly considered a subspecies of Geoffroy's Spider Monkey.cite book|title=New Perspectives in the Study of Mesoamerican Primates|chapter=Taxonomy and Distributions of Mesoamerican Primates|author=Rylands, A., Groves, C., Mittermeier, R., Cortes-Ortiz, L., and Hines, J.|year=2006|page=67–69|isbn=0-387-25854-X]

References

External links

* [http://www.natureserve.org/infonatura/ Infonatura]
*ARKive – [http://www.arkive.org/species/GES/mammals/Ateles_geoffroyi/ images and movies of the black-handed spider monkey "(Ateles geoffroyi)"]