Squirrel

Taxobox
name = Squirrel


image_width = 250px
image_caption = Eastern Gray Squirrel, "Sciurus carolinensis"
regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Rodentia
familia = Sciuridae
subdivision_ranks = Genera
subdivision = Many, see the article Sciuridae.A squirrel is one of the many small or medium-sized rodents in the family Sciuridae. In the English-speaking world, "squirrel" commonly refers to members of this family's genera "Sciurus" and "Tamiasciurus", which are tree squirrels with large bushy tails, indigenous to Asia, the Americas and Europe. Similar genera are found in Africa. The Sciuridae family also include flying squirrels, as well as ground squirrels such as the chipmunks, prairie dogs, and woodchucks. Members of the family Anomaluridae are sometimes misleadingly referred to as "scaly-tailed flying squirrels" although they are not closely related to the true squirrels.

Etymology

The word "squirrel", first attested in 1327, comes via Anglo-Norman "esquirel" from the Old French "escurel", the reflex of a Latin word "sciurus" which was itself borrowed from Greek.cite web | url=http://www.etymonline.com/index.php?term=squirrel | title=Squirrel | work=Online Etymology Dictionary | accessdate=2008-02-07] The native Old English word, "ācweorna", only survived into Middle English (as "aquerna") before being replaced.The word itself comes from the Greek word σκιουρος, "skiouros", which means shadow-tailed, because they use their tail to shade their whole body.

Background

Common squirrels include the Fox Squirrel ("S. niger"); the Western Gray Squirrel ("S. griseus"); the Douglas Squirrel ("Tamiasciurus douglasii"); the American Red Squirrel "T. hudsonicus"; and the Eastern Grey Squirrel ("S. carolinensis"), of which the "Black Squirrel" is a variant.

Unlike rabbits or deer, squirrels cannot digest cellulose and must rely on foods rich in protein, carbohydrates, and fat. In temperate regions early spring is the hardest time of year for squirrels, since buried nuts begin to sprout and are no longer available for the squirrel to eat, and new food sources have not become available yet. During these times squirrels rely heavily on the buds of trees. Squirrels are omnivores; they eat a wide variety of plant food, including nuts, seeds, conifer cones, fruits, fungi and green vegetation, as well as insects. Ground and tree squirrels are typically diurnal, while flying squirrels tend to be nocturnal – except for lactating flying squirrels and their offspring, who have a period of diurnality during the summer. [cite journal | last=Törmälä | first=Timo | coauthors=Vuorinen, Hannu; Hokkanen, Heikki | year=1980 | title=Timing of circadian activity in the flying squirrel in central Finland | journal=Acta Theriologica | volume=25 | issue=32-42 | pages=461–474 | url=http://acta.zbs.bialowieza.pl/contents/?art=1980-025-32-42-0461 | accessdate=2007-07-11]

Predatory behavior by various species of ground squirrels, particularly the thirteen-lined ground squirrel, has been noted. [cite journal | last=Friggens | first=M. | coauthors= | title=Carnivory on Desert Cottontails by Texas Antelope Ground Squirrels | journal=The Southwestern Naturalist | volume=47 | issue=1 | pages=132–133 | year=2002 | doi=10.2307/3672818] Bailey, for example, observed a thirteen-lined ground squirrel preying upon a young chicken. [cite journal | last=Bailey | first=B. | coauthors= | title=Meat-eating propensities of some rodents of Minnesota | journal=Journal of Mammalogy | volume=4 | issue= | pages=129 | month= | year=1923 | url= | accessdate=] Wistrand reported seeing this same species eating a freshly-killed snake. [cite journal | last=Wistrand | first=E.H. | coauthors= | title=Predation on a Snake by "Spermophilus tridecemlineatus" | journal=American Midland Naturalist | volume=88 | issue=2 | pages=511–512 | year=1972 | doi=10.2307/2424389] Whitaker examined the stomachs of 139 thirteen-lined ground squirrels, and found bird flesh in four of the specimens and the remains of a short-tailed shrew in one; [cite journal | last=Whitaker | first=J.O. | title=Food and external parasites of "Spermophilus tridecemlineatus" in Vigo County, Indiana | journal=Journal of Mammalogy | volume=53 | issue=3 | pages=644–648 | year=1972 | doi=10.2307/1379067] Bradley, examining white-tailed antelope squirrels' stomachs, found at least 10% of his 609 specimens' stomachs contained some type of vertebrate — mostly lizards and rodents. [cite journal | last=Bradley | first=W. G. | coauthors= | title=Food habits of the antelope ground squirrel in southern Nevada | journal=Journal Of Mammalogy | volume=49 | issue=1 | pages=14–21 | doi=10.2307/1377723 | year=1968] Morgart (1985) observed a white-tailed antelope squirrel capturing and eating a silky pocket mouse. [cite journal | last=Morgart | first=J.R. | coauthors= | title=Carnivorous behavior by a white-tailed antelope ground squirrel "Ammospermophilus leucurus" | journal=The Southwestern Naturalist | volume=30 | issue=2 | pages=304–305 | doi=10.2307/3670745 | month=May | year=1985] Black squirrels in Russia have been accused of pack behavior in the killing and consumption of a dog. [cite news|url=http://news.bbc.co.uk/2/hi/europe/4489792.stm|publisher=BBC News|date=2005-12-01|accessdate=2008-07-07|title=Russian squirrel pack 'kills dog']

Relationship with humans

Squirrels are generally clever and persistent animals.Fact|date=September 2008 In residential neighborhoods, they are notorious for eating out of bird feeders, digging in planting pots and flower beds to pull out bulbs which they chew on or to either bury or recover seeds and nuts and for inhabiting sheltered areas including attics and basements. Squirrels use their keen sense of smell to locate buried nuts and can dig extensive holes in the process. Birds, especially crows, will watch a squirrel bury a nut and will dig it up as soon as the squirrel leaves. Although expert climbers, and primarily arboreal, squirrels also thrive in urban environments that are largely free of trees.Fact|date=October 2008

Squirrels are sometimes considered pests because of their propensity to chew on various edible and inedible objects. This characteristic trait aids in maintaining sharp teeth, and because their teeth grow continuously, prevents over-growth. Homeowners in areas with a heavy squirrel population must keep attics and basements carefully sealed to prevent property damage caused by nesting squirrels. A squirrel nest is called a "drey". Some homeowners resort to more interesting ways of dealing with this problem, such as collecting and planting fur from pets such as domestic cats and dogs in attics. This fur will indicate to nesting squirrels that a potential predator roams and will encourage evacuation. Fake owls and scarecrows are generally ignored by the animals, and the best way to prevent chewing on an object is to coat it with something to make it undesirable: for instance a soft cloth or chili pepper paste or powder. Squirrel trapping is also practiced to remove them from residential areas.

Squirrels can be trained to be hand-fed. Because they are able to cache surplus food, they will take as much food as is available. Squirrels living in parks and campuses in cities have learned that humans are typically a ready source of food. Squirrels are occasionally kept as household pets, provided they are selected young enough and are hand raised in a proper fashion. They can be taught to do tricks, and are said to be as intelligent as dogs in their ability to learn behaviors. In these cases, a large cage and a balanced diet with good variety will keep a pet squirrel healthy and happy. As a pet, the owner must be aware of "spring fever" at which time a female pet squirrel will become very defensive of her cage, thinking of it as her nest, and will become somewhat aggressive to defend the area.

Squirrels are often the cause of power outages. They can readily climb a power pole and crawl across a power line. The animals will climb onto transformers or capacitors looking for food. If they touch a high voltage conductor and a grounded portion of the device at the same time, they are then electrocuted and cause a short circuit that shuts down equipment. Squirrels have brought down the high-tech NASDAQ stock market twice and were responsible for a spate of power outages at the University of Alabama. [cite web | author=K. Muston | work=Daily Kos: | title=Getting Squirrely | url=http://www.dailykos.com/story/2007/9/22/10818/1400 | accessdate=2008-02-07] They will often chew on tree branches to sharpen their teeth but cannot tell the difference between a tree branch and a live power line. Rubber plates ("squirrel guards") are sometimes used to prevent access to these facilities.

Squirrels are blamed for economic losses to homeowners, nut growers, forest managers in addition to damage to electric transmission lines. These losses include direct damage to property, repairs, lost revenue and public relations. While dollar costs of these losses are sometimes calculated for isolated incidents, there is no tracking system to determine the total extent of the losses. [ [http://hgic.clemson.edu/pdf/pcwdtree_squirrels.pdf Tree Squirrels - University of Georgia] ]

Squirrels are also responsible for burrowing into sensitive earthworks such as dams and levees, causing a loss of structural integrity which requires diligent maintenance and prevention. Squirrel burrowing activity has sometimes resulted in catastrophic failures of these structures. [cite web | author= | title=Levee Safety Program: Burrowing Animals | url=http://www.valleywater.org/water/watersheds_-_streams_and_floods/Taking_care_of_streams/Levee_safety/Burrowing_animals.shtm | publisher=Santa Clara Valley Water District | date=2006 | accessdate=2008-02-07]

, a somewhat common ailment found in malnourished squirrels. [cite web | author=Susan Saliga | title=Backyard Squirrel Feeding Tips | work=Wisconsin Squirrel Connection | url=http://home.wi.rr.com/frettchen/BACKYARD%20SQUIRREL%20FEEDING%20TIPS.htm | accessdate=2007-02-07] [cite web | author=Sara Rowe | title=Squirrel Tales: Care Instructions For Infant Squirrels | work=Squirreltales | url=http://www.squirreltales.org/#Section-H | accessdate=2007-02-07]

Hunting and food

Squirrel meat is considered a favored meat in certain regions of the United States where it can be listed as wild game.Fact|date=September 2008 This is evidenced by extensive recipes for its preparation found in cookbooks, including older copies of "The Joy of Cooking". Squirrel meat can be exchanged for rabbit or chicken in recipes although squirrel meat is more tender than the latter. Squirrels can often become prey to different dogs that have the speed and agility to catch them. Its light red or pink flesh has only a slight game taste. In many areas of the U.S., particularly areas of the American South, squirrels are hunted for food. However, the American Heart Association has found squirrels to be high in cholesterol.cite encyclopedia| title=Squirrel | encyclopedia=Oxford Companion to Food | last=Davidson | first=Alan | volume=| pages=p. 750| publisher=Oxford University Press | date=1999 | isbn=0192115790]

In June 2008 Britain's The Daily Telegraph reported that squirrel was among the most popular meats to cook with and serve at dinner parties. Specifically, they are cooking with the gray squirrel, which is being praised for its low fat content and the fact that it comes from free range sources. Some British are eating the gray squirrel as a direct attempt to help the native red squirrel which has been dwindling since the introduction of the gray squirrel in the 19th century. [ [http://www.telegraph.co.uk/portal/main.jhtml?xml=/portal/2008/05/28/ftsquirrel128.xml First, catch your squirrel...] ]

Popular culture

Despite periodic complaints about the animal as a pest, general public opinion towards the animal is favorable, thanks to its agreeable appearance, intelligence and its eating styles and habits. Squirrels are popular characters in cartoons and other forms of media, such as the works of Beatrix Potter, Redwall (including Jess Squirrel and numerous other squirrels), the squirrel Pattertwig in C. S. Lewis's book Prince Caspian, Michael Tod's Woodstock Saga - novels on squirrel communities in the style of Watership Down, the Starwife and her subjects from Robin Jarvis's Deptford novels, Scrat from Ice Age, Slappy Squirrel of "Animaniacs", Sandy Cheeks from SpongeBob SquarePants, Hammy from Over The Hedge, Benny in "The Wild", Rodney from Squirrel Boy, Secret Squirrel, Screwy Squirrel, Conker the Squirrel from Rare's Conker series of video games, the squirrel-themed super-heroine Squirrel Girl, , Nutty from Happy Tree Friends, and Rocky, Bullwinkle's partner in adventures. Grace from the webcomic El Goonish Shive is often pictured as an anthropomorphic squirrel since it is her most natural and favored form.

Albino squirrels

The Albino Squirrel Preservation Society was founded at the University of Texas at Austin in 2001, and its sister chapter at University of North Texas (UNT) petitioned for an election to name their albino squirrel as the university's secondary mascot. The student body narrowly rejected the call. [cite journal | title='Baby' is no more | journal=North Texan | publisher=University of North Texas | volume=56 | issue=3 | month=Fall | year=2006 | url=http://www.unt.edu/northtexan/archives/f06/untnews.htm | accessdate=2008-02-07] University of Louisville in Kentucky has a documented population of albino squirrels.

Olney, Illinois, known as the "White Squirrel Capital of the World," is home of the world's largest known albino-squirrel colony. Kenton, Tennessee is home to about 200 albino squirrels. There are also albino squirrels on the main campus of Ohio State University in Columbus, Ohio. Brevard, North Carolina and Marionville, Missouri have a substantial population of white (not albino) squirrels. Western Kentucky University has a locally famous population of white squirrels. Exeter, Ontario in Canada is known for having non-albino white squirrels, believed to be the result of a genetic mutation in the early 20th century. White squirrels are also commonly seen in Dayton, Ohio and on the campus of Youngstown State University in Youngstown, Ohio. The snow belt in Western and Central New York (Buffalo, Rochester, and Syracuse) also has a significant white squirrel populationFact|date=April 2008.

Red and grey squirrels in the UK

A decline of the red squirrel and the rise of the eastern grey squirrel has been widely remarked upon in British popular culture. It is mostly regarded as the invading greys driving out the native red species. [cite web | author= | title=The Grey/Red Debate | work=Save our Squirrels | url=http://www.saveoursquirrels.org.uk/red-squirrel-information/the-greyred-debate | publisher=Red Alert North England | date= | accessdate=2008-02-07] Evidence also shows that Grey squirrels are vectors of the Squirrel parapoxvirus for which no vaccine is presently available and which is deadly to red squirrels but does not seem to affect the host. [cite web| author = BBC | title = Virus threatens UK's red squirrels | url=http://news.bbc.co.uk/1/hi/sci/tech/2829015.stm| date = | accessdate=2008-05-30] Currently the red squirrel only resides in a few isolated areas of the UK, notably in Scotland, and in England Formby, the Lake District and the Isle of Wight. Special measures are in place to contain and remove any infiltration of grey squirrels into these areas.

Under British law, the eastern grey squirrel is regarded as vermin, and it is illegal to release any into the wild; any caught must be either killed or kept captive.

See also

* Squirrel fishing
* Twiggy the Water-Skiing Squirrel

References

External links

* [http://tolweb.org/Sciuridae/16456 Tree of Life: Sciuridae]
* [http://www.geocities.com/Heartland/Lane/4033/index.html The Scholarly Squirrel] : general information about squirrels