How big does a Marsh rice rat get? Here is an overview over the average adult age:
A grown Marsh rice rat (Oryzomys palustris) reaches an average size of 13.3 cm (0′ 6″).
When born, they have an average size of 0 cm (0′ 0″). During their lifetime of about 2.33 years, they grow from 3 grams (0.01 lbs) to 53 grams (0.12 lbs). A Marsh rice rat has 4 babies at once. The Marsh rice rat (genus: Oryzomys) is a member of the family Muridae.
As a reference: Humans reach an average body size of 1.65m (5′ 5″) while carrying 62 kg (137 lbs). A human woman is pregnant for 280 days (40 weeks) and on average become 75 years old.
The marsh rice rat (Oryzomys palustris) is a semiaquatic North American rodent in the family Cricetidae. It usually occurs in wetland habitats, such as swamps and salt marshes. It is found mostly in the eastern and southern United States, from New Jersey and Kansas south to Florida and northeasternmost Tamaulipas, Mexico; its range previously extended further west and north, where it may have been a commensal in corn-cultivating communities. Weighing about 40 to 80 g (1.4 to 2.8 oz), the marsh rice rat is a medium-sized rodent that resembles the common black and brown rat. The upperparts are generally gray-brown, but are reddish in many Florida populations. The feet show several specializations for life in the water. The skull is large and flattened, and is short at the front.John Bachman discovered the marsh rice rat in 1816, and it was formally described in 1837. Several subspecies have been described since the 1890s, mainly from Florida, but disagreement exists over their validity. The Florida Keys population is sometimes classified as a different species, the silver rice rat (Oryzomys argentatus). Data from the mitochondrial cytochrome b gene indicate a deep divergence between populations east of Mississippi and those further west, which suggests that the western populations may be recognized as a separate species, Oryzomys texensis. The species is part of the genus Oryzomys, which also includes several others occurring further south in Mexico, Central America, and northwestern South America, some of which have previously been regarded as subspecies of the marsh rice rat. One, Oryzomys couesi, occurs with the marsh rice rat in Tamaulipas and southern Texas.The marsh rice rat is active during the night, makes nests of sedge and grass, and occasionally builds runways. Its diverse diet includes plants, fungi, and a variety of animals. Population densities are usually below 10 per ha (four per acre) and home ranges vary from 0.23 to 0.37 ha (0.57 to 0.91 acres), depending on sex and geography. Litters of generally three to five young are born after a pregnancy around 25 days, mainly during the summer. Newborns are helpless at birth, but are weaned after a few weeks. Several animals prey on the marsh rice rat, including the barn owl, and it usually lives for less than a year in the wild. It is infected by many different parasites and harbors a hantavirus that also infects humans. The species is not of conservation concern, but some populations are threatened.
Animals of the same family as a Marsh rice rat
We found other animals of the Muridae family:
- Fat sand rat with 3 babies per litter
- Crafty vesper mouse with a weight of 27 grams
- Lukolela swamp rat with a weight of 42 grams
- Banana climbing mouse with 2 babies per litter
- Creek groove-toothed swamp rat with 4 babies per litter
- Boehm’s gerbil with 4 babies per litter
- Geoxus valdivianus with 3 babies per litter
- Andean big-eared mouse with a weight of 38 grams
- Yellow-rumped leaf-eared mouse with a size of 12.1 cm (0′ 5″)
- Mexican vole with a size of 11.1 cm (0′ 5″)
Animals with the same size as a Marsh rice rat
Not that size really matters, but it makes things comparable. So here are a couple of animals that are as big as Marsh rice rat:
- Nelson’s kangaroo rat with a size of 12.7 cm (0′ 5″)
- Vinogradov’s jird with a size of 15.5 cm (0′ 7″)
- Long-tailed hopping mouse with a size of 13.8 cm (0′ 6″)
- Mazama pocket gopher with a size of 14.5 cm (0′ 6″)
- Grassland mosaic-tailed rat with a size of 10.8 cm (0′ 5″)
- White-tipped Oldfield mouse with a size of 11.4 cm (0′ 5″)
- Broad-footed mole with a size of 14.2 cm (0′ 6″)
- Mittendorf’s striped grass mouse with a size of 11.1 cm (0′ 5″)
- Little woolly mouse opossum with a size of 13.7 cm (0′ 6″)
- Colorado chipmunk with a size of 12.2 cm (0′ 5″)
Animals with the same litter size as a Marsh rice rat
Here is a list of animals that have the same number of babies per litter (4) as a Marsh rice rat:
- Boehm’s gerbil
- Short-tailed bandicoot rat
- Black-tailed gerbil
- Hazel dormouse
- Indian bush rat
- Thomas’s pine vole
- Utah prairie dog
- Iberian shrew
- Turkestan rat
- Least chipmunk
Animals with the same life expectancy as a Marsh rice rat
Completely different animals, but becoming as old as a Marsh rice rat:
- Cinereus shrew with an average maximal age of 1.92 years
- Salt marsh harvest mouse with an average maximal age of 2.58 years
- Fawn antechinus with an average maximal age of 2.25 years
- Cinnamon antechinus with an average maximal age of 2 years
- Slender-tailed dunnart with an average maximal age of 2 years
- Mediterranean water shrew with an average maximal age of 2 years
- Laxmann’s shrew with an average maximal age of 2 years
- Honey possum with an average maximal age of 2 years
- Long-tailed giant rat with an average maximal age of 2 years
- Golden mouse with an average maximal age of 2.5 years
Animals with the same weight as a Marsh rice rat
As a comparison, here are some other animals that weight as much as the Oryzomys palustris:
- Long-tailed mouse bringing 63 grams to the scale
- Arends’s golden mole bringing 52 grams to the scale
- False water rat bringing 45 grams to the scale
- Grayish mouse opossum bringing 47 grams to the scale
- Large fruit-eating bat bringing 61 grams to the scale
- Lesser musky fruit bat bringing 47 grams to the scale
- Panamanian spiny pocket mouse bringing 51 grams to the scale
- Dusky-footed elephant shrew bringing 57 grams to the scale
- Rock dormouse bringing 46 grams to the scale
- Córdoba vesper mouse bringing 49 grams to the scale