Bushy-tailed Woodrat
Encyclopedia
The Bushy-tailed Woodrat, Packrat, or Woodrat (Neotoma cinerea) is a species of rodent
in the family Cricetidae
.
It is found in Canada
and the United States
.
Its natural habitat
s are boreal forest
s, temperate forests, dry savanna
, temperate shrubland
, and temperate grassland
.
The Bushy-tailed Woodrat is the original "pack rat
", the species in which the trading habit
is most pronounced. It has a strong preference for shiny objects and will drop whatever it may be carrying in favor of a coin or a spoon.
-like; bushy, and flattened from base to tip.
These woodrats are good climbers and have sharp claws. They use their long tails for balance while climbing and jumping, and for added warmth.
These rodents are sexually dimorphic, with the average male about 50% larger than the average female.
Adult length: 11 to 18 in (27.9 to 45.7 cm), half of which is tail.
Weight: Up to 1.3 lb (589.7 g).
The bushy-tailed woodrat is the largest and most cold-tolerant species of woodrat.
, ranging from arctic
Canada
down to northern Arizona
and New Mexico
, and as far east as the western portions of the Dakota
s and Nebraska
.
s. Their preferred habitat is in and around rocky places, so they are often found along cliffs, canyons, talus
slopes, and open rocky fields. They readily adapt to abandoned buildings and mines.
They can be found from sea level
up to 14,000 feet (4300 m), but they become increasingly restricted to higher elevations toward the southern end of their range.
These woodrats do not do as well in old-growth forests. They are found with greater frequently and in higher densities in more open habitats.
s, fruit
s, nut
s, seed
s, mushroom
s, and some animal matter. One study in southeastern Idaho
found grass
, cactus
, vetch
, sagebrush
, and mustard plant
s in the diet, as well as a few arthropod
s. In drier habitats, they will concentrate on succulent plant
s.
These rodents get all their water from their food, and they do not need to drink.
, through scent marking and physical confrontations. Fights consist largely of biting and scratching, and may result in serious injury.
Breeding occurs in spring and summer (May through August), with a gestation period
of approximately 5 weeks. A female may have 1 or 2 litters each year. Litters can range in size from 2 to 6, with a typical litter size of 3. The females have only four mammary gland
s, so larger litters most likely have higher attrition rates. Females have been observed breeding as soon as twelve hours after giving birth, and may be pregnant with one litter while nursing another.
Gestation period in captivity is 27–32 days. Newborns weigh approximately 15 g. Eyes open at around 15 days old, and weaning occurs at 26–30 days.
Males leave the mother at 2½ months. Females often stay in the same area as the mother, with an overlapping range. This is a clear exception to their territorial natures, and this relationship is not currently well understood. The daughters may share food caches with the mother, increasing their likelihood of survival, and the higher female density of the area may also help attract males.
Females breed for the first time when they are yearlings.
, they can occasionally be seen during the day. They are usually solitary and very territorial.
These woodrats collect debris in natural crevices, and abandoned man-made structures when available, into large, quasi-structures for which the archaeologists' term 'midden
' has been borrowed. Middens consist of plant material, feces
, and other materials which are solidified with crystallized urine
. Woodrat urine contains large amounts of dissolved calcium carbonate
and calcium oxalate
s due to the high oxalate content of many of the succulent plants upon which these animals feed.
An important distinction to make is between middens and nests. Nests are the area where the animal is often found and where the females raise their young. Nests are usually within the midden, but there are regional variations to this rule. When not contained within the midden, the nest is usually concealed in a rocky crevice behind a barricade of sticks.
In coniferous forests, the woodrat may build its house as high as 50 feet (15 m) up a tree.
Bushy-tailed woodrats do not hibernate. They build several food caches, which they utilize during the winter months.
The bushy-tailed woodrat engages in hindfoot-drumming when alarmed. It will also drum when undisturbed, producing a slow, tapping sound.
s, bobcat
s, black bears
, coyote
s, weasel
s, marten
s, and hawk
s. Interestingly, the sheltered conditions offered by the midden are often utilised by reptiles during the colder months. The rattlesnake, normally a predator of the wood rat in the warmer months, is a common lodger.
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
in the family Cricetidae
Cricetidae
The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, and New World rats and mice...
.
It is found in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
Its natural habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s are boreal forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s, temperate forests, dry savanna
Savanna
A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
, temperate shrubland
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
, and temperate grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
.
The Bushy-tailed Woodrat is the original "pack rat
Pack rat
A packrat, also called a woodrat, can be any of the species in the rodent genus Neotoma. Packrats have a rat-like appearance, with long tails, large ears and large black eyes. Compared to deer mice, harvest mice and grasshopper mice, packrats are noticeably larger and are usually somewhat larger...
", the species in which the trading habit
Trading habit
Trading habit is a behaviour exhibited by rodents in which they will drop an item that they are currently carrying in favour of another, more attractive item. It is particularly pronounced in the Bushy-tailed Woodrat, which may incorporate a wide range of natural and manufactured items in its...
is most pronounced. It has a strong preference for shiny objects and will drop whatever it may be carrying in favor of a coin or a spoon.
Description
Bushy-tailed woodrats can be identified by their large, rounded ears, and their long, bushy tails. They are usually brown, peppered with black hairs above with a white underside and feet. The top coloration may vary from buff to almost black. The tail is squirrelSquirrel
Squirrels belong to a large family of small or medium-sized rodents called the Sciuridae. The family includes tree squirrels, ground squirrels, chipmunks, marmots , flying squirrels, and prairie dogs. Squirrels are indigenous to the Americas, Eurasia, and Africa and have been introduced to Australia...
-like; bushy, and flattened from base to tip.
These woodrats are good climbers and have sharp claws. They use their long tails for balance while climbing and jumping, and for added warmth.
These rodents are sexually dimorphic, with the average male about 50% larger than the average female.
Adult length: 11 to 18 in (27.9 to 45.7 cm), half of which is tail.
Weight: Up to 1.3 lb (589.7 g).
The bushy-tailed woodrat is the largest and most cold-tolerant species of woodrat.
Range
Bushy-tailed woodrats are found in western North AmericaNorth America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, ranging from arctic
Arctic
The Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost...
Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
down to northern Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
and New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
, and as far east as the western portions of the Dakota
The Dakotas
The Dakotas is a collective term that refers to the U.S. states of North Dakota and South Dakota together. The term has been used historically to describe the Dakota Territory, and is continued to be used to describe the collective heritage, culture, geography, fauna, sociology, the economy, and...
s and Nebraska
Nebraska
Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River....
.
Habitat
Bushy-tailed woodrats occupy a wide range of habitats, from boreal forests to desertDesert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
s. Their preferred habitat is in and around rocky places, so they are often found along cliffs, canyons, talus
Scree
Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...
slopes, and open rocky fields. They readily adapt to abandoned buildings and mines.
They can be found from sea level
Sea level
Mean sea level is a measure of the average height of the ocean's surface ; used as a standard in reckoning land elevation...
up to 14,000 feet (4300 m), but they become increasingly restricted to higher elevations toward the southern end of their range.
These woodrats do not do as well in old-growth forests. They are found with greater frequently and in higher densities in more open habitats.
Diet
The bushy-tailed woodrat prefers green vegetation (leaves, needles, shoots), but it will also consume twigTwig
A twig is a small thin terminal branch of a woody plant. Twigs are critically important in identification of trees, shrubs and vines, especially in wintertime. The buds on the twig are an important diagnostic characteristic, as are the abscission scars where the leaves have fallen away...
s, fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
s, nut
Nut (fruit)
A nut is a hard-shelled fruit of some plants having an indehiscent seed. While a wide variety of dried seeds and fruits are called nuts in English, only a certain number of them are considered by biologists to be true nuts...
s, seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s, mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
s, and some animal matter. One study in southeastern Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
found grass
Grass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...
, cactus
Cactus
A cactus is a member of the plant family Cactaceae. Their distinctive appearance is a result of adaptations to conserve water in dry and/or hot environments. In most species, the stem has evolved to become photosynthetic and succulent, while the leaves have evolved into spines...
, vetch
Vicia
Vicia is a genus of about 140 species of flowering plants commonly known as vetches. It is in the legume family . Member species are native to Europe, North America, South America, Asia and Africa. Some other genera of their subfamily Faboideae also have names containing "vetch", for example the...
, sagebrush
Sagebrush (plant)
Sagebrush is the common name for Artemisia tridentata and a number of other species of shrubby plants in the genus Artemisia, native to the North American west and other parts of the world. It is sometimes confused with sage plants ....
, and mustard plant
Mustard plant
Mustards are several plant species in the genera Brassica and Sinapis whose small mustard seeds are used as a spice and, by grinding and mixing them with water, vinegar or other liquids, are turned into the condiment known as mustard or prepared mustard...
s in the diet, as well as a few arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s. In drier habitats, they will concentrate on succulent plant
Succulent plant
Succulent plants, also known as succulents or fat plants, are water-retaining plants adapted to arid climates or soil conditions. Succulent plants store water in their leaves, stems, and also in roots...
s.
These rodents get all their water from their food, and they do not need to drink.
Reproduction and lifecycle
Males establish dominance in their territoriesTerritory (animal)
In ethology the term territory refers to any sociographical area that an animal of a particular species consistently defends against conspecifics...
, through scent marking and physical confrontations. Fights consist largely of biting and scratching, and may result in serious injury.
Breeding occurs in spring and summer (May through August), with a gestation period
Gestation period
For mammals the gestation period is the time in which a fetus develops, beginning with fertilization and ending at birth. The duration of this period varies between species.-Duration:...
of approximately 5 weeks. A female may have 1 or 2 litters each year. Litters can range in size from 2 to 6, with a typical litter size of 3. The females have only four mammary gland
Mammary gland
A mammary gland is an organ in mammals that produces milk to feed young offspring. Mammals get their name from the word "mammary". In ruminants such as cows, goats, and deer, the mammary glands are contained in their udders...
s, so larger litters most likely have higher attrition rates. Females have been observed breeding as soon as twelve hours after giving birth, and may be pregnant with one litter while nursing another.
Gestation period in captivity is 27–32 days. Newborns weigh approximately 15 g. Eyes open at around 15 days old, and weaning occurs at 26–30 days.
Males leave the mother at 2½ months. Females often stay in the same area as the mother, with an overlapping range. This is a clear exception to their territorial natures, and this relationship is not currently well understood. The daughters may share food caches with the mother, increasing their likelihood of survival, and the higher female density of the area may also help attract males.
Females breed for the first time when they are yearlings.
Behavior
Bushy-tailed woodrats are active throughout the year. While primarily nocturnalNocturnal animal
Nocturnality is an animal behavior characterized by activity during the night and sleeping during the day. The common adjective is "nocturnal"....
, they can occasionally be seen during the day. They are usually solitary and very territorial.
These woodrats collect debris in natural crevices, and abandoned man-made structures when available, into large, quasi-structures for which the archaeologists' term 'midden
Midden
A midden, is an old dump for domestic waste which may consist of animal bone, human excrement, botanical material, vermin, shells, sherds, lithics , and other artifacts and ecofacts associated with past human occupation...
' has been borrowed. Middens consist of plant material, feces
Feces
Feces, faeces, or fæces is a waste product from an animal's digestive tract expelled through the anus or cloaca during defecation.-Etymology:...
, and other materials which are solidified with crystallized urine
Urine
Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
. Woodrat urine contains large amounts of dissolved calcium carbonate
Calcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
and calcium oxalate
Calcium oxalate
Calcium oxalate is a chemical compound that forms needle-shaped crystals, known in plants as raphides. A major constituent of human kidney stones, the chemical is also found in beerstone, a scale that forms on containers used in breweries...
s due to the high oxalate content of many of the succulent plants upon which these animals feed.
An important distinction to make is between middens and nests. Nests are the area where the animal is often found and where the females raise their young. Nests are usually within the midden, but there are regional variations to this rule. When not contained within the midden, the nest is usually concealed in a rocky crevice behind a barricade of sticks.
In coniferous forests, the woodrat may build its house as high as 50 feet (15 m) up a tree.
Bushy-tailed woodrats do not hibernate. They build several food caches, which they utilize during the winter months.
The bushy-tailed woodrat engages in hindfoot-drumming when alarmed. It will also drum when undisturbed, producing a slow, tapping sound.
Predators
Bushy-tailed woodrats are preyed upon by many predators, including: spotted owlSpotted Owl
The Spotted Owl, Strix occidentalis, is a species of true owl. It is a resident species of forests in western North America, where it nests in tree holes, old bird of prey nests, or rock crevices. Nests can be between 13 and 66 yards high and usually contain two eggs...
s, bobcat
Bobcat
The bobcat is a North American mammal of the cat family Felidae, appearing during the Irvingtonian stage of around 1.8 million years ago . With twelve recognized subspecies, it ranges from southern Canada to northern Mexico, including most of the continental United States...
s, black bears
American black bear
The American black bear is a medium-sized bear native to North America. It is the continent's smallest and most common bear species. Black bears are omnivores, with their diets varying greatly depending on season and location. They typically live in largely forested areas, but do leave forests in...
, coyote
Coyote
The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...
s, weasel
Weasel
Weasels are mammals forming the genus Mustela of the Mustelidae family. They are small, active predators, long and slender with short legs....
s, marten
Marten
The martens constitute the genus Martes within the subfamily Mustelinae, in family Mustelidae.-Description:Martens are slender, agile animals, adapted to living in taigas, and are found in coniferous and northern deciduous forests across the northern hemisphere. They have bushy tails, and large...
s, and hawk
Hawk
The term hawk can be used in several ways:* In strict usage in Australia and Africa, to mean any of the species in the subfamily Accipitrinae, which comprises the genera Accipiter, Micronisus, Melierax, Urotriorchis and Megatriorchis. The large and widespread Accipiter genus includes goshawks,...
s. Interestingly, the sheltered conditions offered by the midden are often utilised by reptiles during the colder months. The rattlesnake, normally a predator of the wood rat in the warmer months, is a common lodger.