bundance in altitudinally and
vegetationally intermediate areas such as upon the Mesa Verde, or in
special habitats, such as the rock ledges, and crevices that are so
abundant on the Mesa. Examples of this group of species are
_Spermophilus variegatus_, _Peromyscus crinitus_, _Peromyscus truei_,
_Neotoma cinerea_, and _Neotoma mexicana_. One species, _Dipodomys
ordii_, is restricted to the desert. Species that are restricted to the
desert and that occur in Montezuma County, Colorado, but that are not
known from the Mesa Verde are _Ammospermophilus leucurus_, _Perognathus
flavus_, and _Onychomys leucogaster_.

Species known to have changed in numbers in the past 50 years are the
mule deer that has increased, and the prairie dog that has decreased.
Possibly beaver have increased along the Mancos River. The muskrat,
mink, beaver, and raccoon usually occur only along the Mancos River, as
there is no other permanent surface water in the Park.

Species such as the bighorn and the marmot that are rare within the
Park, or those such as the chickaree, the prairie dog, the wandering
shrew, the montane vole, and the long-tailed vole that occupy only small
areas of suitable habitat within the Park are the species most likely to
be eliminated by natural changes, or through the activities of man. For
example parasites introduced through domestic sheep that wander into the
range of bighorns within the Park might endanger the bighorn population.
An increase in grazing activity, road building, and camping in Prater
and Morfield canyons might eliminate the small areas of habitat occupied
by the montane vole and the wandering shrew. Fire in Chickaree Draw
could destroy all the Douglas fir there, and consequently much of the
habitat occupied by the chickaree.

Probably some species inhabit the Mesa that have not yet been found, but
they are probably few, and their discovery will not alter the faunal
pattern in which the few boreal species occupy restricted habitats in
the higher parts of the Mesa, and a preponderance of geographically
wide-spread species occupy all or most of the Mesa, and surrounding
areas. Additional bats are the species most likely to be added to the
list.

28-7577

LITERATURE CITED

ANDERSON, S.
1959. Mammals of the Grand Mesa, Colorado. Univ. Kansas Publ., Mus.
Nat. Hist, 9(16):405-414, 1 fig. in text.

CAHALANE, V.H.
1948. The status of mammals in the U.S. National Park System, 1947.
Jour. Mamm., 2