SCIENTIFIC NAME:
Blarina carolinensis
STATUS:
Poorly known. Found statewide except for northeastern region. Little is known about the species in 黑料天堂, but may be common in a variety of habitats. MODERATE CONSERVATION CONCERN.
DESCRIPTION:
Southern short-tailed shrews are small, gray, short tailed mammals similar in overall appearance to rodents. However, these animals are not rodents, but actually members of the family Soricidae within the order Insectivora. Southern short-tailed shrews range from 2.8-4.2 inches long and weigh 0.5-1.0 ounces.
Their furred tails are always less than half the length of their head and body. They have long movable pointed snouts, small eyes, and small ears which are nearly concealed by their soft, dense fur. Southern short-tailed shrews are typically grayish black, but sometimes have a silvery or brownish cast to their fur. Their undersides are somewhat lighter in color than their upper parts. This species is well adapted for digging, having strong wide front feet which are somewhat larger than their hind feet. Southern short-tailed shrews are so similar in appearance to other short-tailed shrew species that chromosome counts are necessary to distinguish among them.
DISTRIBUTION:
Southern short-tailed shrews inhabit the southeastern United States. Their range includes all or part of Virginia, North Carolina, South Carolina, Georgia, Florida, 黑料天堂, Mississippi, Tennessee, Kentucky, Illinois, Arkansas, Louisiana, and Texas.
HABITAT:
Southern short-tailed shrews inhabit a wide variety of terrestrial habitats, but are most commonly found in moist, well drained, hardwood forests or in pine stands where deep organic matter makes burrowing for food and shelter relatively easy. They are frequently associated with the borders of forest meadows, which also provide plentiful food and cover. Habitually dry areas tend to be avoided, likely because of their poor potential as a source of food. Also, southern short-tailed shrews are rarely found in areas where the soil is frequently saturated with water due to flooding of their burrow systems.
FEEDING HABITS:
Southern short-tailed shrews are primarily nocturnal predators with very high metabolic rates and high activity levels. Though they always seem to be in a hurry, they are relatively slow moving. A fast walking man can easily overtake one caught outside its burrow. Their diet consists primarily of annelids, arachnids, centipedes, crustaceans, insects, insect larvae, mollusks, some vegetable matter (seeds, nuts, fruits, and fungi), and small vertebrates. They are known to store living snails in their burrows for winter consumption. It is during the winter when most vegetable matter is consumed.
The saliva of short-tailed shrews contains mild venom which has the ability to paralyze their prey. This poison, produced by submaxillary glands, is introduced into prey through wounds inflicted by their teeth. It is toxic enough to kill mice, but is not a danger to humans. Southern short-tailed shrews consume 50-150% of their body weight in food each day.
LIFE HISTORY AND ECOLOGY:
Southern short-tailed shrews construct burrow systems which have two levels, one near the surface with a second, connected and deeper layer (16-24 inches below the surface). Many of their burrows are built beneath logs, which may themselves be honeycombed with tunnels if they are rotten. Males and females share a burrow during the breeding season. Moreover, short-tailed shrews are social animals with several non-mated individuals often inhabiting the same burrow system. Though sharing burrow systems, these animals usually move and hunt alone. Runways are used as sites for food storage. Southern short-tailed shrews build their own tunnels under the ground or snow, but will also readily use those constructed by other animals.
Southern short-tailed shrews burrow using a combination of their strong forefeet, head and nose. They have been documented burrowing at a rate of up to a foot per minute in soft soil. Home ranges for this species vary from 0.5 to 2.0 acres, and population densities of up to 25 per acre have been recorded. Southern short-tailed shrews use a strong smelling secretion from an abdominally located gland to mark their runways and territories as well as for sex recognition during the breeding season. Breeding occurs from February through November with gestation requiring 21-30 days.
Young are reared in underground nests of grass, leaves, and hair, which are located in the deeper regions of their burrows. Litter size varies from two to six young with two to four litters produced each year. Young are pink, blind and helpless at birth weighing only slightly more than one gram. Young southern short-tailed shrews鈥 eyes open and they are weaned when 18-22 days old. At this point, they begin to venture outside the nest. Sexual maturity is reached at approximately six weeks of age for males and 12 weeks of age for females. Southern short-tailed shrews are prey to many species, including snakes, hawks, owls, foxes, coyotes, weasels, and skunks. Very few live as long as two years in the wild.
REFERENCES:
McCay, T. 2001. Mammalian Species. Blarina carolinensis. American Society of Mammalogists no. 673, pp. 1-7.
鈥淪outhern Short-Tailed Shrew. The Mammals of Texas-Online Edition鈥
鈥淪outhern Short-tailed Shrew 鈥 Wikipedia, the free encyclopedia鈥
鈥淪mithsonian National Museum of Natural History. North American Mammal. Blarina carolinensis Southern Short-tailed Shrew.
鈥淭he Venom List 鈥 Southern Short-tailed Shrew鈥
Author:
John S. Powers, Wildlife Biologist, Division of Wildlife and Freshwater Fisheries
