| Preble's shrew | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Eulipotyphla |
| Family: | Soricidae |
| Genus: | Sorex |
| Species: | S. preblei |
| Binomial name | |
| Sorex preblei Jackson, 1922 | |
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| Preble's shrew range | |
Preble's shrew (Sorex preblei) is a small shrew distributed across the Great Basin of the United States and southern British Columbia in Canada.
The Preble's shrew has gray pelage on its dorsal side and silvery pelage on the ventral side. Like many other shrews, the Preble's shrew has a long snout, conspicuous ears, small eyes and plantigrade feet. The Preble's shrew is the smallest member of its genus in North America. [2]
Preble's shrew ranges from 77 to 95 mm (3.0 to 3.7 in) in total length, with a tail length of 28–38 mm (1.1–1.5 in), hind feet of 7–11 mm (0.28–0.43 in) and an ear length of 8–11 mm (0.31–0.43 in). [3] Besides the relatively small body length, the Preble's Shrew has several distinctive cranial characteristics. The length of its teeth are typically less than 6.5 millimeters, and the length of mandibular tooth row (C1-M3) are usually found to be less than 4.1 millimeters. The height of the coronoid process has been found to be less than 3.3 millimeters. [4]
The Preble's shrew is known to live in Western North America, from the Columbia Plateau to the northern Great Plains. Specimens have been found in northeastern California, northern Nevada, [5] central and eastern Oregon, southeast Washington, western Idaho, all of Montana, western Wyoming, central Colorado and north of the south shores of the Great Salt Lake in Utah. [6] Shrew fossils have even been found as far south as New Mexico. [7] In Canada, the shrew can only be found in south-central British Columbia. [8] The Preble's shrew typically ranges in elevation from 1280m-2550m. [9]
Most Preble's shrews live in arid or semiarid shrub-grasses that are associated with coniferous forest dominated by sagebrush. However, these shrews are not restricted to this habitat. They have been found In Oregon living on the big transition zone meadows. In another part of Oregon, these shrews have been found in marsh habitats. A majority of Preble's shrews have been captured in arid habitats, frequently in the immediate or nearby presence of sagebrush. This is likely for protection. Specimens captured in southwestern Wyoming were found in sagebrush-steppe areas: In southern British Columbia, Preble's shrews were captured in lightly grazed grasslands surrounded by scattered stands of Douglas-fir (Pseudotsuga menziesii) or ponderosa pine (Pinus ponderosa). [10]
Little is known about the lifestyle of this shrew, but it probably has a similar lifestyle as other shrews in its ecosystem. These other shrews are often active during both the day and night. It is probable that the Preble's shrew is active all year. Shrews have been captured in the spring and late summer in southwestern Wyoming [11] and during the summer, fall and spring in British Columbia. [12] In Nevada, these shrews have been collected in the summer and fall. [13] Preble's shrews have even been collected in mid-winter in Utah. [14] Collection records from Montana range from mid-February to early November. [15]
The reproductive biology of Preble's shrews has not been well studied, and is largely unknown. [16] One study focused on 26 female specimens captured in southeastern Oregon from June and July 1999. Five adult females contained developing embryos: two with 3 embryos, two with 5, and one with 6; mean = 4.4 embryos; All 13 specimens had elongated nipples and extensive mammary tissue, which suggested that each individual had previously produced at least one litter prior to their capture. Four juvenile females exhibited no evidence of reproductive activity. For 16 males, testis size in 15 of the 16 individuals was either less than 2.0 cubic millimeters, signifying that these males were non-reproductive, presumably captured in the year of birth or more than 16.0 cubic millimeters suggesting that they were older and reproductive.; one male with intermediate testis size had little wear on I1, indicating it may have just reached sexual maturity. The data collected in this study suggest that at least two litters were produced prior to the June and July pregnancies. [17]
Other shrews that live in the same ecosystem as the Preble's shrew include Sorex cinereus , S. haydeni, S. merriami, S. monticolus, S. nanus, and S. vagrans . [18] Preble's shrews have been collected in Montana in close association with Sorex cinereus and S. monticolus. [19]
Measurements of population trends, vital statistics and estimates of population density have not been thoroughly studied. At nearly all of the locations where several species of shrews have been captured in association with Preble's shrew, it is always one of the less abundant species, suggesting competitive exclusion. [20] Predators of Preble's shrew have not been reported or well documented.
The Preble's shrew has been an Animal Candidate Reviewed for Listing as Endangered or Threatened Species twice in recent history but is currently not listed as an endangered or threatened species. [21] No conservation efforts are currently being undertaken. [22]
The diet of Preble's shrew has not been well described, but it likely resembles the diets of other cinereus-group shrews, which feed on small insects and other small invertebrates (worms, molluscs, centipedes, etc.). It has a relatively low bite force, which suggests that it feeds on soft-bodied prey. [23]
The red-toothed shrews of the subfamily Soricinae are one of three living subfamilies of shrews, along with Crocidurinae and Myosoricinae. In addition, the family contains the extinct subfamilies Limnoecinae, Crocidosoricinae, Allosoricinae and Heterosoricinae. These species are typically found in North America, northern South America, Europe and northern Asia. The enamel of the tips of their teeth is reddish due to iron pigment. The iron deposits serve to harden the enamel and are concentrated in those parts of the teeth most subject to wear. Members of the genera Chimarrogale, Nectogale, Neomys (Nectogalini) and some members of Sorex (Soricini) are known as water shrews, due to having a semi-aquatic lifestyle.
The cinereus shrew or masked shrew is a small shrew found in Alaska, Canada, and the northern United States. This is the most widely distributed shrew in North America, where it is also known as the common shrew.
The American pygmy shrew is a small shrew found in Northern Alaska, Canada, and the northern United States, south through the Appalachian Mountains. It was first discovered in 1831 by naturalist William Cane in Georgian Bay, Parry Sound.
The marsh shrew, also known as the Pacific water shrew, Bendire's water shrew, Bendire's shrew and Jesus shrew is the largest North American member of the genus Sorex. Primarily covered in dark-brown fur, it is found near aquatic habitats along the Pacific coast from southern British Columbia to northern California. With air trapped in its fur for buoyancy, marsh shrews can run for three to five seconds on top of the water. It measures about 16 cm (6.3 in) in length, including a 7-centimetre (2.8 in)-long tail, and weighs an average of 14.5–16 g (0.51–0.56 oz). The marsh shrew's diet consists mainly of invertebrates, which it hunts on land and in the water. They are rare; their populations are thought to be in decline, and they are considered endangered in parts of their range.
The genus Sorex includes many of the common shrews of Eurasia and North America, and contains at least 142 known species and subspecies. Members of this genus, known as long-tailed shrews, are the only members of the tribe Soricini of the subfamily Soricinae. They have 32 teeth.
The Olympic shrew is a rare species of shrew that lives in only 13 spots in northwest Washington state and, a recent discovery, in Burns Bog, located in Delta, BC.
The Pribilof Island shrew is a small, short tailed species of mammal in the family Soricidae (shrews). It is endemic to and found only on Alaska's Pribilof Islands. Due to its distinct tricoloured coat, it was originally thought to be related to the Arctic shrew, but it is in fact much closer to the Cinereus shrew in its geographical distribution and morphological traits. Not much is known about the population size, breeding habits, ecology, and the general biology of the shrew.
The dwarf shrew is a species of mammal in the family Soricidae endemic to Arizona, Colorado, Montana, Nebraska, New Mexico, South Dakota, Utah, and Wyoming in the United States. The type locality is Estes Park, Colorado, USA.
The ornate shrew is a species of mammal in the family Soricidae (shrews). It is endemic to western North America, ranging from Northern California in the United States to Baja California in Mexico. Eight subspecies are known, including the extinct tule shrew, known only from four specimens collected in 1905, and the Suisun ornate shrew, a species of conservation concern in California. Through skull morphology research and genetic testing on Ornate shrew populations, it has been shown that there are three main genetic subdivisions: The Southern, Central and Northern. These three genetic subdivisions of Ornate shrew arose from populations of Ornate shrews getting geographically isolated from other populations.
The Inyo shrew is a species of shrew found in the western United States. It is light gray and white in color, with a narrow skull and small body size, very similar in appearance to the related dwarf shrew, but paler and not as large. It can be found in many different habitats, from rocky, mountainous regions to wetlands and riparian areas. Not much is known about its behavioral and reproductive habits. While barely studied, their population is believed to be stable and not under any threat.
Trowbridge's shrew is a species of mammal in the family Soricidae. It is found in southern British Columbia in Canada and in Washington, Oregon, and California in the United States.
There are at least 50 small mammal species known to occur in Yellowstone National Park.
Endogone is a genus of fungi in the family Endogonaceae of the division Zygomycota. The genus has a widespread distribution, especially in temperate regions, and contains about 20 species.
