is a vole?
do voles look like?
do voles live?
role do voles play in the Great Salt Lake Playa FOOD WEB?
do voles eat?
do voles reproduce?
mammals of the Great Salt Lake
Voles of the Great Salt Lake
is a vole?
The Great Salt Lake is famous
for its brine shrimp and birds, but there are also many mammals that live
on the shore of the lake and are an important part of the shoreline, playa
ecosystem. One of these mammals is a small rodent called voles. Voles
are members of the genus Mictrotus. There are more than one
hundred species of voles, each adapted to immensely varying habitat from
sea level to the timber line. Voles are important to humans because
their voracious appetites can cause agricultural damage but in the Great
Salt Lake Playa Ecosystem they are of food value to numerous larger carnivores.
The two voles found in the in the Great Salt Lake Ecosystem are the Meadow
Vole or “Field Mouse”- Mictrotus pennsylvanicus and the Montane
(or Mountain) Vole - Mictotus montanus.
do voles look like?
Photo from University
Most voles look alike and
this is true with the Meadow Vole and the Montane Vole. Meadow voles
have variable color from yellowish brown to reddish brown peppered with
black to blackish brown. They are usually grey with silver-tipped
hair below and a long tail dark above and paler below. The feet of
Meadow Voles are dark. The Meadow Vole is 140 -195 mm in length,
33-64 mm tall, and weighs between 20 -70 grams. The Montane Vole
is similar with a grizzled brown or blackish color above, often with buff
tint and gray below. Montane Voles are moderately long with a bicolored
tail. Feet of Montane Voles feet are dusky or silvery gray.
They are 140 -192 mm in length, 31 - 69 mm tall and weight between 37-85
Drawing by Farrell R.
Collett from Mammals of the Intermountain West
do voles live?
In the World -
In North America
the Intermountain West by Zeveloff
Meadow Vole: Alaska
(except for Northern sections) and Canada south and east to Northern Washington,
Idaho, Utah, New Mexico,Wyoming, Northern Missouri, Northern Illinois,
Kentucky, Northeast Georgia, and South Carolina.
Montane Vole: South-central
British Colombia, Eastern Washington,
most of Oregon, Northeast California east to Souteast Montana,Eastern Wyoming,
portions of Northern Utah and Western Colorado,extending south into New
Mexico and extreme East Arizona.
Society Field Guide to North American Mammals by John Whittaker
In the Great Salt Lake Ecosystem
Vole Surface trails
by M.E. Richmond from UC Pest Management Guidelines
In general, Voles lives
in runway and burrow systems under the grass cover.
Meadow Vole: Lush grassy
fields and marshes, swamps, woodland glades and mountain tops. Like Meadow
voles, Montane voles construct a system of burrows
among the grass.
Voles hide in the dense grass
vegetation and retreat into their tunnel system to seek refuge from predators.
part do voles play in the Great Salt
do voles eat?
Voles eat a wide variety
of foods including, almost any grasses, or herbaceous plants as well as
seeds. However studies have shown that the Meadow and Montane voles
that inhabit the Salt Grass Zone rely virtually entirely on salt
grass (Distichlis stricta) for food resource throughout the
year. Voles create their distinctive grass cuttings by reaching up
and cutting of the stalk then pulling it down and cutting again until the
seeds are reached. All of the grass with the exception of the tough
outer stalk is eaten by the Vole. Their voracious appetite results
in voles eating almost its own weight in food daily. Since many types of
insects find refuge in the tunnel systems of voles, they also could provide
an important source of protein during certain times of the year.
Many carnivorous inhabitants
of the Great Salt Lake depend of voles for food resources. Predators
of voles include carnivorous mammals such as badgers
and coyotes, snakes, and predatory birds such as the marsh
hawks and owls. Because voles are relatively defenseless and
so widespread they constitute the mainstay in the diet of many carnivores.
do voles reproduce?
Voles put a large portion
of its energy into high, rapid, and early
reproduction rather than
growth and longevity. The gestation period is 21 days and litters
range in size from 1-11 offspring are produced from spring through fall.
Up to thirteen litters have been produced in a single season. A study
by Negus et al. (1985) has shown that vole reproduction may be initiated
by a chemical factor, 6-methoxybenzoxazolinone (6-MBOA). (6-MBOA)
occurs in sprouted wheat. The study showed that young sprouts of
salt grass in late February are high in (6-MBOA), late June samples are
lower and there is no detectable (6-MBOA) in salt grass samples from August.
The seasonal onset of breeding coincides with the appearance of (6-MBOA)
in the newly sprouted salt grass and supplemental (6-MBOA) also can initiate
breeding in a non-breeding winter population.
If a vole population grows
too large they can be serious pests in agricultural areas such as orchards
where they remove the bark of the tree in a circle at the base, “girdling
trees” and killing them.
there any other small mammals in the Great Salt Lake ecosystem?
There are also many other small
mammals that live on the shore of the lake or
on the dry desert uplands adjacent to the saline playas. and are an
important part of the ecosystem.
These small mammals include:
· the least chipmunk
- Eutamias minimus pictus
· little pocket mouse
- Pergnathus longimembris gulosus
· kangaroo mouse
- Microdipodops megacephalus leucotis
· ord kangaroo rat
- Dipodmys ordii pallidus
· chisel toothed
kangaroo rat - Dipodmys microps bonnevillei
· deer mouse - Peromyscus
· harvest mouse -
Reithrodomys megalotis megalotis
· grasshopper mouse
- Ocychomys leucogaster utahensis
· antelope ground
squirrel - Citellus leucurus leucurus
do these mammals look like?
These small mammals are all
rodents and may look alike. Characteristics of each mammals are as
· The least chipmunk
is a small chipmunk with varying sizes. In dry regions a muted yellowish
gray above with tan dark stripes. In moister areas, brownish gray with
black side stipes. All least chipmunks have pale white stripes of
equal width, 2 white areas on flanks continue to base of tail, sides are
orange brown and belly grayish white. The tail is long and brown
above grayish yellow below, with hairs black tipped.
· The little pocket
mouse is a soft furred grayish yellow or buff above with interspersed
black hairs that vary with color of soil. Under parts are buff, brownish,
or white. The tail of the little pocket mouse is uniformly pale brownish
and there are two white patches at the base of the ears. They are
110 -151 mm long, 53-86 mm tall and from 7-9 grams in weight.
· The kangaroo
mouse is blackish or dark grayish above, with gray hairs at the base
and white below. The tail of the kangaroo mouse is thickest in the
middle, tapered at both ends, black tip, and no tuft. The hind foot
has hair on the soil. Kangaroo mice are 148 -177 mm long, 68 -103
mm tall and from 10 -17 grams in weight.
· The ord kangaroo
rat is buffy reddish, or blackish above and white below. The
tail is crested but not white tipped and relatively shorter than other
kangaroo mouse. There is a dark tail stripe below extending to the
tip. There may be conspicuous white spots at the base of the ears
and above the eyes. The hind foot has 5 toes. The ord kangaroo
mouse is 208 -282 mm long 100-163 mm tall and from 50-96 grams in weight.
· The chisel-toothed
kangaroo mouse is also buff to dusky above and whitish below.
It has a long tail with white side stripes narrower than dark upper and
lower stripes. The hind foot has 5 toes. The chisel-toothed kangaroo
mouse is 244-297 mm in length, 134 -175 mm tall and from 55 -75 grams in
· The color of the
deer mouse varies with geographic area, it is often grayish to reddish
above and white below. The tail is distinctly bicolored and short-haired.
The deer mouse ranges from 119-222 mm in length, 46-123 mm in height and
10-33 grams in weight.
· The harvest
mouse is brownish above, buff along the sides, and white below.
There is an indistinct broad strip down the spine. Tail length is
less than that of head and body. They are 114-170 mm long, 50-96
mm tall and from 9-21.9 grams in weight.
· The grasshopper
mouse is a heavy bodied mouse with 2 main colors phases above; grayish
and cinnamon-buff and white below. The tail is short, thick and bicolored
with a white tip. It is usually less than one third total length.
The grasshopper mouse is from 130 -190 mm long 29-62 mm tall and weights
· The antelope
ground squirrel has buff upper parts in summer gray in winter.
There is one narrow stripe on each side and its underparts are white with
black-tipped hairs forming narrow borders. The upperside of the tail
has one black band and ears are small. Length is from 194-239 mm,
54-87 mm tall and 85-156 grams in weight.
do they live in the Great Salt Lake?
Great Salt Lake Ecosystem
Zone - deer mouse and ord Kangaroo rat
- chisel-toothed kangaroo rat (dominant), antelope ground squirrel, least
chipmunk, kangaroo mice, pocket mice, harvest mice, deer mice, and grasshopper
Shadscale Gray molly
Zone - deer mice (sparse)
Shadscale Gray molly-Greasewood
Zone - antelope ground squirrel, least chipmunk (abundant), chisel-toothed
kangaroo rat, deer mice (abundant)
Zone - antelope ground squirrel, least chipmunk, deer mice as well
as others in sparse numbers.
- chisel-tooth kangaroo rat (dominant), deer mouse (sparse), antelope ground
- ord kangaroo rat (dominant), antelope ground squirrel, deer mouse.
- chisel toothed kangaroo rat (dominant), deer mouse, antelope ground squirrel,
ord kangaroo rat (sparse), little pocket mice, grasshopper mouse.
do they eat?
ord kangaroo rat -
Mostly succulent terminal leaf buds and leaves. Also greasewood,
tumbleweed and grasses.
rat - Mostly shadscale. Also four-winged saltbush and greasewood.
little pocket mouse
- Rice grass, alkali sacaton, pepper grass and tumbleweed.
antelope ground squirrel
- Alkali sacaton shoots, rice grass, cheat grass, galleta grass, seeds,
as well as carnivorous habits
These small mammals are prey
for the larger carnivores of the Great Salt Lake. These include badgers,
kit foxes, coyotes, and carnivorous birds.
Burt, William H., Grossenheider,
Richard P. A Field Guide to the Mammals. New York, Houghton Mifflin, 1980.
Cahalane, Victor A. Mammals
of North America. New York, MacMillian Company,1947
Fautin, Reed W. Biotic Communities
of the Northern Desert Shrub Biome in Western Utah. University of Illinois,
Hall, E. Raymond Ph.D. The
Mammals of North America. Second Ed. John Willey and Sons, New York, 1981.
Whitaker, John O. National
Audubon Society Field Guide to North American Mammals. Chanticleer Press,
New York, 1996.
Vest, Dean E. The Plant Communities
and Associated Fauna of Dugway Valley in Western Utah. University
of Utah, 1962
Zeveloff, Samuel I. Mammals
of the Intermountain West. University of Utah Press. 1988
University of California.
Pest Management Guidelines <URL-http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7439.html>
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