Dall's Sheep
Physical
Description
Dall’s sheep are pure white with amber-colored horns. Rams weigh
from 160 to 242 pounds and ewes are smaller at 110 to 150
pounds; both stand 3 to 3 ½ feet high at the shoulder. Rams and
ewes both grow horns throughout their lives, but those of the
ewe are less curved, more slender and shorter (about ten inches
long) than the ram's. The horns of a ram stop growing each fall,
resulting in annual growth rings which, like tree rings, can be
used to determine the age of the ram.
Average Weight Range
Adult Dall’s sheep weigh between 110 and 245 pounds.
Reproduction
Dall’s sheep mature slowly and have low reproductive rates.
Females normally reach breeding age at three years of age and
produce only one lamb per year. Males breed when their horns are
large enough for them to establish a dominant position in the
ram hierarchy, usually at seven to nine years.
With the approach of the breeding season in October and early
November, head-butting and clashing among rams increases. In a
clash, two rams several yards apart rise up on their hind legs
and slam forward and downward into each other. Such contests are
usually won by the larger rams, which will have the advantage
when the ewes are in estrus and ready for breeding.
A dominant ram will guard an estrus ewe for 2 to 3 days until
she indicates her willingness to mate. After breeding, the ram
will seek out additional estrus ewes.
The rut extends from mid-November to mid-December followed by a
gestation period of about 175 days. For protection from
predators, ewes seek out steep terrain to give birth. About a
week after the lambs are born, ewes and lambs group together in
nursery bands, which remain in the lambing area for 3 to 4 weeks
before moving on to the summer range.
Food Usage/Selection
Dall’s sheep eat grasses, sedges, broad-leaved plants and dwarf
willows. In winter, when these foods are scarce, the sheep add
lichens to their diet. The distribution and availability of
forage requires the sheep to move seasonally between traditional
summer and winter ranges. The animals supplement their diet with
regular visits to mineral licks.
Range
Dall’s sheep are found in Alaska and northwestern Canada.
Habitat
Dall’s sheep live mostly above timberline on ridges, dry
meadows, and steep mountain slopes. There usually are rocky
outcrops and cliffs nearby. They are generally high- country
animals but sometimes occur in rocky gorges below timberline. In
the mountains, snow may accumulate in some places and be almost
completely swept off by winds in other places, such as low
plateaus and ridges. It is these latter areas that are important
as winter range from October to May, especially if they are
adjacent to precipitous escape terrain. The total size of the
winter range used by Dall's sheep is usually much smaller than
the summer range. In early summer, as the snow melts, sheep
expand their movements to incorporate recently exposed, greening
vegetation, generally at higher elevations.
Common Hunting Methods
Spot and stalk is the common method for hunting Dall’s sheep.
Stalking of the sheep occurs only after extensive glassing of
the slopes. Because sheep are continuously surveying lower
terrain, the objective is to approach sheep from above. Most
hunters utilize high-powered rifles, as long-range shots are the
norm.
Hunting Challenges/Values
Rough and rocky conditions at high altitudes can be very
dangerous for hunters. The Dall's sheep's keen eyesight, smell,
and hearing quickly alert them to predators, or hunters. The
size of their horns and their majestic mounts make them an
extremely sought after possession.
Interesting Tidbits
It takes about eight years for the trademark circular horns of a
Dall’s ram to grow to full size. These horns are made of
keratin, the same substance as fingernails.
Although their thickened skulls are an adaptation to the
tremendous impact of their head-butting, it is not uncommon for
rams to have bloodied faces and splintered, or broomed, horn
tips.
Dall’s sheep travel to sites called “licks” to eat the
mineral-rich dirt, which balances their diet.
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