Barbary Sheep*
Order Artiodactyla : Family
Bovidae : Ammotragus lervia (Pallas)
Description. A relatively large sheep with horns curving outward,
backward, and then inward and marked with strong transverse wrinkles;
horns of females similar but somewhat smaller; tail relatively long,
reaching nearly to hocks and with long hairs on terminal half; a
conspicuous growth of long hair on throat, chest, and upperparts of
front legs; no beard as is found in goats; upperparts and outer surface
of legs uniform rufous or grayish brown; blackish mid-dorsal line from
head to middle of back; flanks, inner surface of legs and belly whitish,
but the chest colored like the sides; horns yellowish brown, darkening
with age, set close together (nearly touching at the bases), and
attaining a length of 50-80 cm. External measurements of a moderately
large adult male: total length, 1,650 mm; tail, 141 mm; hind foot (tip
of hoof to hock), 363 mm; ear, 116 mm; height at shoulder, 950 mm.
Weight of males up to 145 kg; females to 65 kg. Dental formula: I 0/3, C
0/0, Pm 3/3, M 3/3 X 2 = 30.
Distribution in Texas. Native to the dry
mountainous areas of northern Africa; introduced into the Palo Duro
Canyon area of Texas in 1957-58, where it has become firmly established.
Also present in the Edwards Plateau, Trans-Pecos, South Texas, Rolling
Plains, and Post Oak Savannah regions as a result of private
introductions.
Habits. This sheep, also called the aoudad, is
adapted to a dry, rough, barren, and waterless habitat — much as is the
native bighorn sheep of our southwestern deserts. Consequently, it is
quite likely that these two could not survive together in the same area
because of competition between them.
These sheep live in small groups comprised of old and
young animals of both sexes. They are expert climbers and can ascend and
descend slopes so precipitous that man can negotiate them only with
great difficulty. Consequently, they are difficult to hunt.
Their food consists of a wide variety of vegetation
including grasses, forbs, and shrubs. Apparently, they are capable of
producing metabolic water and can survive for long periods without
access to fresh water. However, when water is available they utilize it
for both drinking and bathing.
In studies conducted in New Mexico, Herman Ogren found
that 79 species of plants were included in the diet of these sheep; of
these, 13 were grasses, 20 were shrubs and the remainder forbs. Mountain
mahogany (Cercocarpus breviflorus) was the most sought-for single
plant. On a yearlong basis this species comprised nearly 22% of the
items found in rumens of the sheep. Ogren found some seasonal variation
in the diet. In winter, grasses comprised 86% of the rumen contents;
browse, 11%; forbs, 3%. In spring, summer, and fall the browse species,
mainly oaks and mountain mahogany, comprised about 60% of the diet;
grasses, about 26%; and forbs (various species of "weeds") made up the
balance. On a yearlong basis, browse species comprised 49% of the diet;
grasses, 42%; forbs, 9%.
The breeding season appears to be rather extended, but
most of the breeding is concentrated in the 2 months from mid-September
to mid-November. The gestation period is about 160 days. Consequently,
most of the lambs are born between late February and late April, but
some lambs are born as late as November.
According to Ogren, females may become sexually mature
at the age of 8 months, but normally they are older. All females 19
months of age or older that were collected in the fall and winter season
were gravid, lactating, or ovulating.
Ogren developed a technique for aging these sheep by
examination of the dentition in the lower jaw. The following scheme is
adapted from his studies:
| Age |
|
Condition of Dentition |
| 3 weeks |
|
Deciduous dentition complete
and consists of four pairs of deciduous incisiform teeth and
three pairs of deciduous premolars. |
| 8 months |
|
First permanent molar
erupted or erupting. |
| 17 months |
|
Second permanent molar
erupting. |
| 18 months |
|
First (inner) permanent
incisor erupts. |
| 21 months |
|
Third permanent molar
erupting; deciduous premolars being replaced. |
| 23 months |
|
Second deciduous incisor
shed. |
| 27 months |
|
Permanent dentition except
for outer two pairs of incisiform teeth; last molar not
fully exposed. |
| 36 months |
|
Third pair of permanent
incisiform teeth present; last molar fully exposed but
unworn. |
| 48 months |
|
Fourth (outer) pair of
deciduous incisiform teeth (the canines) being replaced. |
| 60 months |
|
Full set of permanent teeth. |
These sheep were first brought to the United States in
about 1900 and have been reared in zoos and on private preserves for a
number of years. They were first released in the wild in New Mexico in
1950 and in Texas in 1957, when 31 were released southwest of Claude in
Armstrong County. Thirteen more were released near Quitaque. These
introductions were highly successful in the Palo Duro Canyon area. By
May of 1966 the population had increased to an estimated 400-500 sheep.
By 1963, the population had increased to such a level that a controlled
hunt was deemed advisable. Forty-two permits were issued; six rams and
three ewes were harvested. In 1964, 50 permits were issued; eight rams
and seven ewes were harvested. In 1965, 70 permits resulted in a harvest
of eight rams and eight ewes. Statewide, the population in 1989 was
estimated at over 20,000.
Whether this animal will eventually become a pest, as
have most of the "successful" introduced animals, remains to be seen.
There is some evidence that they compete directly with mule deer for
food. They also have been observed feeding on winter wheat crops growing
adjacent to Palo Duro Canyon. In the Trans-Pecos, Barbary sheep may have
a deleterious impact on bighorn sheep reintroduction efforts.
* nonnative species
|