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Geomys breviceps

Cladus: Eukaryota
Supergroup: Opisthokonta
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Superclassis: Tetrapoda
Classis: Mammalia
Subclassis: Theria
Infraclassis: Placentalia
Ordo: Rodentia
Subordo: Castorimorpha
Familia: Geomyidae
Genus: Geomys
Species: Geomys breviceps
Subspecies: G. b. braviceps - G. b. sagittalis

Name

Geomys breviceps Baird, 1855

References

* Geomys breviceps in Mammal Species of the World.
Mammal Species of the World: A Taxonomic and Geographic Reference, 2 Volume Set edited by Don E. Wilson, DeeAnn M. Reeder
* IUCN link: Geomys breviceps Baird, 1855 (Least Concern)


Links

* North American Mammals: Geomys breviceps [1]


Vernacular names
English: Baird’s Pocket Gopher

The Baird’s Pocket Gopher or Louisiana Pocket Gopher (Geomys breviceps)[2] is a species of pocket gopher that is native to the Southern United States. In total, there are three almost identical species of eastern pocket gopher; Geomys attwateri, Geomys bursarius, and Geomys breviceps. Geomys breviceps are larger in size, the Geomys attwateri are medium and the Geomys bursarius are a bit smaller.[3] The only variation is in size, but other than this they are un-identifiable by external features. Baird’s Pocket Gophers are small rodents with the majority of their weight set on their top half.

Baird’s Pocket Gopher is native to eastern Texas, western Louisiana, eastern Oklahoma and southwestern Arkansas.[2] It is a burrowing creature, meaning it digs tunnels and generally lives underground, except during the rainy seasons. It has sharp, long, curved front claws designed specifically for digging. Generally, they are safe from predators since it lives underground, though other burrowing rodents such as badgers and long tailed weasels may pose a threat. Baird’s Pocket Gopher has bacteria in its digestive system, allowing it to digest various grasses and they are able to re-ingest fecal pellets.[2] It is polygamous and has a high reproductive rate which is one of the main reasons for its survival. On average, Baird’s Pocket Gopher has two to three babies per litter.[3] It lives about 1 to 2 years in the wild.[3]

Habitat

Baird's Pocket Gopher is commonly located on the Gulf Coastal Plains of Eastern Texas in three different soil types. It is found in fine sandy Lufkin and Ochlocknee soil types where the topsoil has a depth of less than 10 centimetres (3.9 in). The third soil type, Wilson sandy loam, becomes hard and compact when it dries, therefore G. breviceps is not inclined to habituate itself in any soil made of dense clay.

The species is less likely to be in soil that has a high moisture content as well. Baird’s pocket gopher lives a solitary life underground with the ability to create burrows. The only time a gopher may retreat from its burrow is during wet months, to avoid being flooded out. Burrows are the common form of living quarters that the pocket gopher creates. On average each burrow is 6 cm (2.4 in) in diameter and are found at depths of 10–68 cm (3.9–27 in) underground, making it possible for only one adult gopher to occupy a single burrow system. Burrow systems are very complex and range from 55–180 cm (22–71 in) in length. The tunnels meander aimlessly through various feeding areas, which indicates that burrowing is primarily done in the search for food. An average mound created by the Geomys breviceps is about 30 × 45 cm (12 × 18 in)in length, and about 8 cm (3.1 in) in height, and is in a crescent shape. During the winter months, the gopher creates special mounds, which contain feeding galleries, a nesting chamber, a "bathroom", and food storage chambers.

Physical description

The pocket gophers are considered to be medium to small in size in the Rodentia Order. Baird's Pocket Gopher has a cylinder shaped body with most of its weight carried near their head. The zygomatic arch is shorter than width of the mouth meaning the dorsal of the animal exceeds the jugal bone. The neck is a little thinner but the heaviest part of the body is carried on the back of the head. The eyes are very small and beadlike and the ears are found only by a meager flap of skin that follows the top of the temple. There are external pouches on the cheeks; these pouches are fur-lined and used for transporting food. The body gradually tapers from the head to the tail, widening a little at the thighs.

Short hair covers the body with range of colors from pale brown to black and usually more pale when you travel towards the belly area. The tail is short, thick, and bare with very little hair found at the base averaging 65 mm (2.6 in). The front feet are used for digging; the feet appear as long curved claws, the rear feet are smaller with an average length of 31 mm (1.2 in). They look identical to the G. attwateri and the G. bursarius and the only they difference is by scientific testing. The males have an average weight of 180–200 g (6.3–7.1 oz) with a cranium length of 19 mm (0.75 in), while the average weight for females is 120–160 g (4.2–5.6 oz) with a cranium length of 19 mm (0.75 in).

Diet

Baird's Pocket Gopher eats grass, tubers, certain roots, and all kinds of other types of plant life.[2] It burrows underground and while they are making their nests they even obtain food from the roots of different plants in their tunnels. They store the food they gather in small pockets called “cheek pouches” on the side of their head that look like black slits; this is where the name “pocket gopher” was thought up from [Tumlison: 1]. If there is no food where they burrow, they at least tend to try and find food that is closer to where they are nesting; it is rarely seen above ground.[2] Like other rodents, Baird's Pocket Gopher has gnawing front teeth called incisors, which makes it easier for the animal to dig through dirt and still gather food [Tumlison: 1].

To make it a simpler process on the Baird’s Pocket Gopher to digest the grasses and plants they eat, their body creates a kind of bacteria called cellulose in their digestive system, helping the body process and digest the grasses and plants better.[2] Like other mammals, or rodents, Baird's Pocket Gopher re-ingests fecal pellets which benefit them during the winter and for the more rainy seasons through out the year. The re-ingestion of fecal pellets increases the efficiency of food utilization which is useful when the plants are scarce in these seasons.[3]

References

1. ^ Linzey, A.V. & NatureServe (Hammerson, G.) (2008). Geomys breviceps. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 29 May 2009.
2. ^ a b c d e f Smithsonian National Museum of Natural History. "Geomys breviceps." North American Mammals. 2009. 7 May 2009. [1]
3. ^ a b c d Davis, W. B. & Schmidly, D. J. (1997). "Baird's Pocket Gopher". The Mammals of Texas-Online Edition. http://www.nsrl.ttu.edu/TMOT1/geombrev.html. Retrieved 10 May 2009. [dead link]


Further reading

* Wilson, Don E. The Smithsonian Book of North American Mammal. UBC Press, 1999 [2]
* Sulentich, James M. and Williams, Lawrence R. "Geomys breviceps." Mammalian Species." 1991. 10 May 2009 [3]

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Source: Wikipedia, Wikispecies: All text is available under the terms of the GNU Free Documentation License