BIOLOGICAL DATA AND HABITAT REQUIREMENTS
WILDLIFE SPECIES: Oreamnos americanus | Mountain Goat 



TIMING OF MAJOR LIFE HISTORY EVENTS : 
Age at sexual maturity - Mountain goats generally breed when they are
2.5 years old [3,16].

Breeding season - The breeding season of mountain goats is from October
through early December.  Mountain goats are polygamous [5,18].

Gestation - The gestation period is 180 days.  Mountain goats generally
give birth to only one kid per year, but twins are not uncommon [5].
Kids are born in May through June [18].

Development of kids - At about 6 weeks of age mountain goats begin to
forage near their mothers.  Weaning occurs in August and September [5].

Life span - Mountain goats may live 12 years or more in the wild [18].


PREFERRED HABITAT : 
Mountain goats inhabit rugged terrain comprised of cliffs, ledges,
projecting pinnacles, and talus slopes.  Mountain goat range is
associated with areas having well-defined glaciation at elevations
between 5,000 and 11,000 feet (1,524-3,353 m).  Goats usually remain at
or above timberline and within reach of rocky outcrops.  Deep snows
frequently force them to lower elevations.  In general, moutain goats
make use of higher elevations during summer and lower ones in winter [5].

In Montana, mountain goat habitat can be divided into four major groups:
grassy slide-rock slopes, ridgetops, alpine meadows, and timber.
Grassy slide-rock slopes are major use areas in spring, summer, and fall.
Alpine meadows are frequented most from July through August.  Timber
areas are utilized during summer and fall by single goats and by nannies
in spring prior to parturition [5].

Winter range - Mountain goat winter ranges are characterized by a lack
of persistent or melt-crusted snow along cliffs, and steep terrain
interspersed with vegetation.  Suitable winter ranges may be at lower
elevations where snow is less abundant and persistent, or on relatively
unforested, steep, mostly south-facing slopes where snow sheds rapidly.
Mountain goats use those portions of winter ranges on slopes exceeding
40 degrees [3].  At low elevations, particularly near the Pacific Coast,
a conifer canopy may benefit wintering mountain goats by intercepting
and redistributing snow and by providing forage. In contrast, goats
wintering on interior ranges, where snowfall is great, tend to avoid
dense stands of conifers that accumulate snow [3].

Salt lick areas - Salt licks are a very important habitat resource.
Peak use of licks occurs in spring and early summer [3].

Summer habitat - During summer mountain goats often use lush stands of
quality herbaceous forage in alpine grasslands and meadows [3].

Migration corridors - Migration corridors are used between summer and
winter ranges and when goats are visiting salt licks [3].  Fall
migrations appear to be influenced by snowfall on the upper ranges and
usually begin around the time of the first snowfall.  Fall movements
generally involve only 3 to 4 miles (5-6.5 km), but migrations of up to
9.5 miles (16 km) are not uncommon.  Upward movement in spring is more
gradual than the fall migrations.  Lone males are generally the first to
arrive at the higher elevations, and females with kids and yearling
goats usually remain at lower levels until the melting snow allows for
more suitable feeding conditions [5].
  
Water - Water is not believed to be a limiting factor on most mountain
goat ranges, as these are either in moist climates or in areas with
persistent snowfields.  However, water availability may restrict goat
movements and habitat selection in southern ranges where the species has
been introduced [3].


COVER REQUIREMENTS : 

Habitat selection by mountain goats is often determined by needs for
security from predation.  One study showed that the distance to cliffs
was the most important factor determining goat distribution and that
summering goats made little use of foraging areas over 1,320 feet (400
m) from cliffs [3].  Only large groups of goats use unsafe habitats
while foraging [17].  Visibility of surroundings is also important to
mountain goats.  Lack of visibility may limit their use of dense stands
of conifers far from escape terrain.  When crossing forested areas
without escape terrain, goats repeatedly use the same trails [3].
 
Kids are born on the steepest, most rugged areas of a goat range [3].
Mountain goat resting sites include rocks, snowbanks, and vegetated
areas.  Goats often utilize high points, especially during good weather,
but seek protection of overhanging rocks and caves during storms or on
unusually hot days [5].


FOOD HABITS : 
Mountain goats eat a variety of plant species.  They will utilize
whatever plants are available [3,4,5].  Grasses, sedges, rushes, forbs,
and shrubs have each been reported as abundant in the diet or as
preferred in both winter and summer studies.  Conifers, mosses, and
lichens are also important winter forages [3,5,8].

In summer feeding areas in Montana, 56 percent of the plants taken were
grasses, sedges, and rushes.  The most important representatives
included tufted hairgrass (Deschampsia caepitosa), sheep fescue (Festuca
ovina), alpine bluegrass (Poa spp.), sedges, and rushes.  Forbs
comprised 24 percent of the grazed plants and included lupine (Lupine
spp.), moutain bluebell (Mertensia spp.), and polemonium (Polemonium
spp.).  Dwarf huckleberry (Vaccinum spp.), willow (Salix spp.), and
swamp current (Ribes spp.) represented the shrubs utilized and comprised
16 percent of the summer diet.  Tree species comprised less than 4
percent of the diet.  Mosses, lichens, and ferns were comsumed in trace
amounts.  Rocky Mountain woodsia (Woodsia scopulina) was the most
important fern and was readily utilized by kids [5].

In Colorado, grasslike species made up approximately 96 percent of the
summer diet, while less than 4 percent of the vegetation consumed
consisted of forbs.  The utilization of grasslike species in winter
decreased slightly, to about 88 percent, and about 12 percent of the
diet consisted of shrub species.  Forbs were not an important component
in the winter diet [5].

In South Dakota, lichens are abundant throughout the mountain goat range
and are highly utilized throughout the year.  Leaves and terminal
branches of chokecherry (Prunus virginiana) also are utilized throughout
the year.  Studies have found that species utilization by mountain goats
in the Black Hills is variable.  During the winter months, the diet
consisted of about 60 percent mosses and lichens, 20 percent bearberry
(Arctostaphylos uva-ursi), 10 percent needles and twigs (Pinus
ponderosa), and 10 percent miscellaneous ferns, grasses, and woody
species [5].


PREDATORS : 
Coyotes (Canis latrans) are common throughout much of the range
inhabited by mountain goats, but their importance as predators is
generally considered insignificant.  Mountain lions (Felis concolor) and
bobcats (Felis rufus) may be important predators in remote ranges [5].

Golden eagles (Aquila chrysaetus) may be the most important predators,
but the total impact is thought to be insignificant.  Several
observations have been made of golden eagles knocking mountain goats
from cliffs and carrying kids away.  Most eagle predation occurs in
spring, when kids are very small [5].

Mountain goats are also hunted by humans.  Goats are mainly considered a
trophy species [5].  Declines related to overharvest have been reported
in the East Kootenay, British Columbia; in Idaho's Pahsimeroi herd; in
southern Yukon Territory; and in the Wallowa Mountains of Oregon [5].


MANAGEMENT CONSIDERATIONS : 
The general limiting factor and cause of mortality in mountain goats is
the lack of suitable forage during the winter months when weather
increases the susceptibility to predation, parasites, disease, and
accidents [5].

In recent years, increased road access, mining activity, timber
harvesting, and demand for the species by trophy hunters has led to the
exploitation of many herds [5].  A primary management concern is
overharvest of mountain goats.  Appropriate levels of harvest could be
achieved if (1) annual data on population size and productivity are
known, (2) harvest levels can be regulated on a local basis, and (3)
illegal kill can be controlled.  However, these requirements are often
impractical [3].

Some mountain goat populations are small and isolated, and gene flow
among such populations seems infrequent.  Any human activities may
inhibit goat movements, especially among males, thus increasing
possibilities for inbreeding [3].


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Oreamnos americanus | Mountain Goat