Marsh rat
| Marsh rat | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Rodentia |
| Superfamily: | Muroidea |
| Family: | Cricetidae |
| Genus: | Holochilus |
| Species: | H. sciureus |
| Binomial name | |
| Holochilus sciureus Wagner, 1842 | |
Marsh rat (Holochilus Sciureus) is a species of rodent in the Cricetidae family.[2] Marsh rat can refer to several not closely related types of semiaquatic rodents of superfamily Muroidea. H. sciureus is widely distributed in north and central South America to central Argentina.[3] It is thought that Holochilus primigeniusmay be the ancestor of the marsh rat.[2][3]
Description
Marsh rats can be distinguished from the web-footed marsh rat (Holochilus brasiliensis) due to its smaller physique.[2] They have a body mass that ranges anywhere from 130g-200g(0.286 lbs-0.441 lbs) with males weighing more than females.[2][4] Head and body lengths are on average approximately 160mm-193mm(6.30 in- 7.60 in), with a tail that is shorter than their head and body.[2] The maximum skull length of H. sciureus is 7.40 inches.[2]
The fur of marsh rats are short and begin with a dark mix on top, usually with black, that fades to a much lighter color such as white with a hint of orange on the underside.[2] Hindfeet are noticeably larger than the forefeet on Marsh rats, with claws that are protuberant, and partially webbed toes.[2] Marsh rats are mostly herbivores and need strong sharp teeth to cut through food such as seeds. The shape of the two upper incisors are flattened laterally and are large for gnawing on food.[3] Molars are flat-crowned cusps, and the enamel bands are a yellow-orange.[2]
Ecology
Range and Habitat
Marsh rats live in Amazon drainage areas, grasslands, and extend to the savannahs of Great British Guiana from sea level to 2,000m.[2][5] The day temperature of these flat areas reach to about 85 °F (Fahrenheit) in the day and in two periods, December to January and May to July, mean annual rainfall is about 1328mm.[4] Marsh rats are found in the thickness of grass around the soil banks within cain and rice fields, along roads and canals.[5] These rodents are nocturnal, semi-aquatic, and building nests above water level in these flooded fields.[5] Marsh rats occasionally become pest in cultivate crops causing damage to crops by gnawing and nest-building activities.[2] The average home range of marsh rats inhabiting a field in Venezuela, based on mark-recapture data, was 2.47 acres.[2]
Diet
Marsh Rats are mostly herbivores but can be insectivores.[5] This rat feeds mainly on grass stalks, mature cane sugar, seeds of savannah grasses, and insects such as beetles.[4][5] Mature sugar cane rodent damage has been responsible for a drop of approximately 12 percent in available sugar.[5] Marsh rats living in flooded rice fields typically feed on the lower part of stems from the rice shoots when the rice is young.[5] Marsh rats are known to feed at night in freshly harvested fields with young shoots.[5] The mean distance a marsh rat would travel suggest that in one night (12 hr) these rodents could travel more than 900m.[4]
Reproduction
Male and female marsh rats are fertile throughout the year and increases with rainfall.[2] Female fertility is greater than 27 percent pregnancy compared to males who are 70-98 percent of individuals with scrotal testes.[2] Females take up to 3.5 days before deciding to mate with a male.[2] The gestation period is 29 days with fetal development increasing by 0.12g/day.[2][5]
Female reproductive success can be limited based on resources available, protection she can give, and how successful she can produce.[4] Male reproductive success is limited to female responsiveness to reproduce with them, and how many females they can fertilize.[4] In both sexes the marsh rat can become territorial, it just depends on the distribution of food for females, and the distribution of females for males.[4] The average litter size of Marsh rats is about 3.47, meaning they can range from having a litter size of about 3-6.[5]
References
- ↑ Weksler, M. Queirolo, D. & Brito, D. (2008). "Holochilus sciureus". IUCN Red List of Threatened Species. Version 2008. International Union for Conservation of Nature. Retrieved 15 November 2015.
- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Barreto, Guillermo R.; García-Rangel, Shaenandhoa (1 December 2005). "Holochilus sciureus". Mammalian Species: 1–5. doi:10.1644/780.1.
- 1 2 3 D’Elía, Guillermo; Hanson, J. Delton; Mauldin, Matthew R.; Teta, Pablo; Pardiñas, Ulyses F. J. (29 September 2015). "Molecular systematics of South American marsh rats of the genus Holochilus (Muroidea, Cricetidae, Sigmodontinae)". 96 (5): 1081–1094. doi:10.1093/jmammal/gyv115.
- 1 2 3 4 5 6 7 Eiris, Gabriela; Barreto, Guillermo. "HOME RANGE OF MARSH RATS, Holochilus sciureus, A RODENT PEST IN RICE FIELDS OF VENEZUELA" (PDF). interciencia.org. interciencia. Retrieved 11 November 2016.
- 1 2 3 4 5 6 7 8 9 10 Twigg, G. I. (1 January 1962). "Notes on Holochilus sciureus in British Guiana". Journal of Mammalogy. 43 (3): 369–374. doi:10.2307/1376946.