but differs in being dusky olive (less reddish) on the upper parts and
orange instead of white on the underparts.
Douglas squirrels range from southern British Columbia southward
to Lower California. They are confined to the Pacific Coastal
region. Although closely related to _Tamiasciurus hudsonicus_, no
intergradation with that species has been found.
The rich coloration of the Douglas squirrel matches the background of
the humid forests it inhabits. It occurs at sea level along the ocean
coast, the shores of Puget Sound and on some islands in Puget Sound.
It ranges through the Transition and Canadian life-zones well into the
Hudsonian.
It makes its home in holes in trees or in nests constructed of conifer
twigs, needles and bark. Old nests of birds may be modified and taken
over, but most outside nests seem to have been made entirely by the
squirrel. Nests are usually placed near the top of denser fir and
cedar trees. Nests are hemispherical in shape, 12 inches or more in
diameter, and open on top. The central cup, 4 inches in diameter, is
lined with strips of inner bark of red cedar coiled but unshredded.
Nests in holes are usually some distance from the ground, but the
entrances to some are at ground level.
The habits of the Douglas squirrels vary with the season. In spring
they are shy. They rarely call and are skillful in keeping branches
or tree trunks between themselves and persons. In June and July
they become bolder, calling more frequently and moving about more.
In September and October they become exceptionally bold. They call
almost incessantly from late morning until early afternoon, and spend
considerable time on the ground.
The call notes of the Douglas squirrel are similar to those of the
red squirrel but are softer, more slurred. The common call is the
long, trilling "burr," loud at first and becoming gradually softer.
On hot afternoons in late summer a barking "pauf" note is given. This
sound is repeated several times at intervals of a minute or so. It
has remarkable carrying power. The danger signal is a loud, explosive
"pe-ee." Another common call is a short barking or chirping "bauf" with
a musical, questioning sound. This is repeated at intervals of a few
seconds when the presence of danger is suspected. At times it, rather
than the loud danger signal, is given also when a person is sighted. A
low chirping note is often given while the squirrel is busily at work.
This is made while the squirrel is moving about. Other calls described
are made from a standing or sitting position and are accompanied by a
jerk or a flick of the tail.
The Douglas squirrel eats seeds of the Douglas fir, seeds of maple,
hazelnuts, dogwood berries and mushrooms. The berries of forest shrubs,
such as the red huckleberry, salal and Oregon grape, may also be eaten.
Two broods of young may be born in a year. The first is born in early
June. Embryos found from June 11 to 28 varied in number from 6 to 8. A
nursing female was taken as early as June 10, 1938, and one was taken as
late as October 10, 1938.
Douglas squirrels commonly have a few fleas and 2 to 5 ticks at the
bases of the ears. No lice, cases of mange, or serious infestations of
parasites have been seen.
=Glaucomys sabrinus= (Shaw)
Northern flying squirrel
[Illustration: FIG. 91. Northern flying squirrel (_Glaucomys
sabrinus_), probably from near Seattle, in Woodland Park Zoo, Seattle,
Washington, January 28, 1941. (Fish and Wildlife Service photo by
Victor B. Scheffer, No. 1137.)]
_Description._--The northern flying squirrel is slightly smaller than
the red squirrel (_Tamiasciurus_). The head and body measure about 7
inches and the tail about 5 inches. The most distinctive feature is
the loose fold of skin that stretches from the wrist of the foreleg to
the ankle of the hind leg. The fur is extremely soft and plushlike. It
is not separated into guard hair and underfur, and because all hairs
are of approximately the same length, the fur appears extremely sleek.
The fur of the tail is of the same texture as that on the body but is
dorso-ventrally compressed. The eyes are large and dark. The color of
the upper parts varies from reddish brown in some races to brownish
gray in others. The underparts are buffy gray.
Flying squirrels range over the forested parts of North America from
Guatemala to Alaska and northern Canada and from the Atlantic to
the Pacific. A closely related genus (_Pteromys_) occurs in Europe.
Two species are found in North America. The small _volans_ ranges
in eastern United States, Mexico, and Guatemala, while the larger
_sabrinus_ occurs in parts of the western United States, most of
Canada, and central Alaska. Near the Great Lakes the two species occur
in the same area, probably in different habitats.
Howell (1918: 16) recognized 18 subspecies of _sabrinus_, five of which
were recorded in the state of Washington. One of these (_olympicus_)
proves to be a synonym of an earlier-named subspecies but another form
(_bangsi_), not recorded for Washington by Howell, has been found in
the Blue Mountains in the southeastern corner of the state (Taylor and
Shaw, 1929: 18).
Flying squirrels are strictly arboreal and occur only in woods and
forests. They prefer areas where trees grow close together and to
considerable heights. Older woods with dead stubs and hollow trees
are preferred. They occasionally invade attics of cabins and other
habitations of man. The old Forestry Building on the University of
Washington Campus, later the home of the Washington State Museum,
was inhabited by flying squirrels for many years. Several specimens
preserved in the Museum prove the poor judgment of the animal in
choosing a natural history museum as a home.
Relatively little is known of the detailed habits of _Glaucomys
sabrinus_ although the life history of the eastern _Glaucomys volans_
has been described. Flying squirrels are active all winter, even in
the high mountains. They are often caught in traps set for fur bearers
and, where trapping is an important means of livelihood, they are
serious pests. Flying squirrels do not actually fly but only glide
through the air. The loose fold of fur between their limbs is stretched
by extending the legs. With it the flying squirrel is able to sail 50
yards or more. The flat tail serves as a rudder and allows the squirrel
to change direction while in flight. Glides end with an upward swoop,
allowing the squirrel to alight, head upwards, on a tree trunk slightly
lower than their starting point.
Unlike other members of the squirrel family, flying squirrels are
completely nocturnal. They are seen in the daytime only when frightened
from their retreats. Homes consist principally of old woodpecker holes
or other cavities in trees. They are said to build outside nests,
similar to those of tree squirrels, but I have found none of these in
Washington. The animals can be frightened from their holes by pounding
on the bases of trees in which their nests are situated. Certain holes
seem to be preferred nesting places. Near Cottage Lake, King County,
two flying squirrels were taken from a woodpecker hole in succeeding
years. Cowan (1936B: 58) discovered remains of 14 nests of flying
squirrels in a single hollow tree near Alta Lake, British Columbia.
According to Cowan, hollow trees are used in winter but the young are
born in outside nests of shredded bark and lichens. The young usually
number 3 and are born in May and June.
[Illustration: FIG. 92. Distribution of flying squirrel in Washington.
A. _Glaucomys sabrinus oregonensis._ B. _Glaucomys sabrinus
fuliginosus._ C. _Glaucomys sabrinus columbiensis._ D. _Glaucomys
sabrinus latipes._ E. _Glaucomys sabrinus bangsi._]
Only once have I heard the voice of a flying squirrel. Near Dewey Lake,
Yakima County, the squirrels were unusually abundant in the black
hemlock and Douglas fir forests of the mountain sides. Here a birdlike
twittering note caught my attention and occasional dark, sailing shapes
were glimpsed against the clear sky. Eight traps set in the afternoon
and visited at 11 p. m. held two flying squirrels. In the morning
another was in a trap. Seemingly the squirrels are active most of the
night.
The food consists principally of conifer seeds and probably other nuts,
seeds, and fruit. They eat the meat bait of traps set for fur bearers
and probably eat the eggs of birds.
=Glaucomys sabrinus oregonensis= (Bachman)
_Pteromys oregonensis_ Bachman, Jour. Acad. Nat. Sci. Philadelphia,
8:101, 1839.
_Sciuropterus alpinus oregonensis_ Rhoads, Proc. Acad. Nat. Sci.
Philadelphia, p. 324, June, 1897.
_Sciuropterus alpinus olympicus_ Elliot, Field Columb. Mus. Publ.
30, zoöl. ser., 1:225, February 1, 1899 (type from Happy Lake,
Clallam County, Washington).
_Glaucomys sabrinus oregonensis_ Howell, N. Amer. Fauna, 44:44,
June 13, 1918.
_Glaucomys sabrinus olympicus_ Howell, N. Amer. Fauna, 44:49, June
13, 1918.
_Type._--Obtained "in pine [= conifer] woods of the Columbia near
the sea" by J. K. Townsend in 1839. Probably near St. Helen,
Columbia County, Oregon (Rhoads, 1897:324).
_Racial characters._--Small size, rich color.
_Measurements._--A male from Cottage Lake, King County, measured:
total length 287; length of tail 125; hind foot 38. A female from
5 miles southeast of Sequim, Clallam County, measured: 303; 133;
41; ear 27. A male from Quilcene, Jefferson County, measured: 311;
140; 41.
_Distribution._--Western Washington west of the Cascade Mountains.
The locality records for flying squirrels in the northern Cascade
Mountains, given by Taylor and Shaw (1929: 18), when plotted on a
distribution map, show overlapping of ranges in this area. The
ranges of the three races involved have been drawn on the
accompanying map (fig. 92) on the basis of geographic probability
and are subject to revision because the specimens from this area
have not been examined.
Marginal records that may apply to _G. s. oregonensis_ are, from
Taylor and Shaw (1929: 18): Nooksack River, Rockport, North Bend
and Skamania.
_Remarks._--Of all the races occurring in Washington,
_oregonensis_ is the most distinct. _Glaucomys s. olympicus_
Elliot must be regarded as a synonym of _oregonensis_.
=Glaucomys sabrinus bangsi= (Rhoads)
_Sciuropterus alpinus bangsi_ Rhoads, Proc. Acad. Nat. Sci.
Philadelphia, p. 321, June, 1897.
_Glaucomys sabrinus bangsi_ Howell, N. Amer. Fauna, 44:38, June
13, 1918.
_Type._--Obtained in Idaho County, Idaho, by Harbison and Bargamin
on March 8, 1897; type in Philadelphia Academy of Natural Sciences.
_Racial characters._--Similar to _oregonensis_ but larger and
paler throughout.
_Measurements._--A female from Wildcat Spring, Columbia County,
measured: total length 333; length of tail 147; hind foot 45; ear
29; weight 151 grams.
_Distribution._--Found only in the Blue Mountains of extreme
southeastern Washington.
=Glaucomys sabrinus columbiensis= Howell
_Glaucomys sabrinus columbiensis_ Howell, Proc. Biol. Soc.
Washington, 28:111, May 27, 1915.
_Type._--Obtained at Okanogan, British Columbia, by Allan Brooks on
May 9, 1898; type in United States National Museum.
_Racial characters._--Larger than _oregonensis_ and paler. Similar
to _bangsi_ but paler, especially beneath, and less reddish above.
_Measurements._--Howell (1918: 46) gives the average of two
subadult topotypes as: total length 313; length of tail 143; hind
foot 42.
_Distribution._--Northeastern Washington, probably extending, from
records of Taylor and Shaw (1929: 18), west to Mazama and Stehekin
and east to Molson.
=Glaucomys sabrinus latipes= Howell
_Glaucomys sabrinus latipes_ Howell, Proc. Biol. Soc. Washington,
28:112, May 27, 1915.
_Type._--Obtained at Glacier, British Columbia, by J. A. Loring, on
August 13, 1894; type in United States National Museum.
_Racial characters._--Similar to _bangsi_ and _columbiensis_ but
with larger feet and grayer color.
_Measurements._--Howell (1918: 49) gives the average of 10
specimens as: total length 342; length of tail 153; hind foot
41.5.
_Distribution._--The Pend Oreille Mountains of extreme
northeastern Washington, north (from records of Taylor and Shaw,
1929: 18-19, as revised) to Sullivan Lake and south to Loon Lake.
=Glaucomys sabrinus fuliginosus= (Rhoads)
_Sciuropterus alpinus fuliginosus_ Rhoads, Proc. Acad. Nat. Sci.
Philadelphia, p. 321, June, 1897.
_Glaucomys sabrinus fuliginosus_ Howell, N. Amer. Fauna, 44:47,
June 13, 1918.
_Type._--Obtained at Martin Station, Kittitas County, Washington,
by Allan Rupert in March, 1893; type in Philadelphia Academy of
Natural Sciences.
_Racial characters._--Similar to _columbiensis_ but underparts
darker and tail paler. Larger and paler than _oregonensis_.
_Measurements._--Three females from the Cascades average: total
length 327; length of tail 145; hind foot 40.7; ear 25.
_Distribution._--The Cascade Mountains, according to Taylor and
Shaw (1929: 18), as revised here, east to Entiat River and south
to Carson.
=Perognathus parvus= (Peale)
Great Basin pocket mouse
_Description._--Great Basin pocket mice are slightly larger than house
mice. The ears are tiny and round; the tail is relatively long, slightly
longer than the head and body; the forefeet are small but the hind feet
are large and powerful, more than one-fourth as long as the head and
body. They have relatively large, fur-lined, external cheek pouches. The
color of the upper parts varies with the subspecies from blackish
olive-gray to buffy olive-gray; a line of clear buff or buffy-olive
extends along the lower part of side, separating the darker color of the
upper parts from the white underparts; the tail is short-haired,
blackish above, olive beneath.
Pocket mice of the genus _Perognathus_ range from Mexico northward to
British Columbia. Only one species, _parvus_, occurs in Washington where
it is represented by three subspecies. Pocket mice are most common in
the Upper Sonoran Life-zone in sandy areas dotted with desert shrubs.
They are found occasionally in dry, grassy places in the Arid Transition
Life-zone. They may be locally abundant in rocky areas and are often
trapped high on talus slides, many yards from the nearest soil. Gray
(1943: 191-193) estimates their numbers on the sagebrush areas of the
Yakima Valley at 32 per acre. They are completely nocturnal. Their
ordinary movements are rather slow and specimens studied by the aid of a
searchlight usually crept quietly into the protection of the nearest
desert shrub. The trail of a pocket mouse in soft sand may be recognized
by the distinctive mark left by the dragging tail.
Burrows of pocket mice usually are at the bases of shrubs where tough
roots furnish protection. They are kept closed during the day by means
of a plug of fresh earth or sand. Openings may often be recognized by a
fan-shaped pile of fresh sand before the hole. Burrows excavated were
usually less than four feet in length and branched from two to four
times. No nests were found in the burrows but one contained a few fresh
stalks of desert annuals. The air in the burrows seemed warm and humid.
The pouches of pocket mice from Washington often contain the fresh,
green tips of desert plants, grass seeds, seeds of plants other than
grasses, and plant leaves. Because of their occasional great abundance,
pocket mice may be a menace to agriculture. Fortunately much of their
habitat is unsuited to farming.
In Washington pocket mice breed in March and April. From 4 to 8 embryos
were found in pregnant females.
=Perognathus parvus parvus= (Peale)
_Cricetodipus parvus_ Peale, U. S. Explor. Exped., 8 (mamm. and
ornith.):53, 1848.
_Perognathus parvus_ Cassin, U. S. Explor. Exped., 8 (mamm. and
ornith.):48, 1858.
_Perognathus parvus parvus_ Miller, Bull. U. S. Nat. Mus.,
128:278, April 29, 1924.
[Illustration: FIG. 93. Distribution of the Great Basin pocket mouse
in Washington. A. _Perognathus parvus parvus._ B. _Perognathus parvus
columbianus._ C. _Perognathus parvus lordi._]
_Type._--Probably obtained in the neighborhood of The Dalles, Wasco
County, Oregon.
_Racial characters._--Size small; upper parts brownish-buff washed
with blackish or, in gray phase, ashy gray washed with blackish;
sides buffy yellow; a buffy spot often present on throat; tail
blackish above, olive below; facial markings usually brownish-buff
but in older animals indistinct and washed with blackish.
_Measurements._--Thirty-one males and 19 females from Washington
average, respectively: total length 169, 164; length of tail 90,
86; hind foot 22.6, 21.8; ear 5, 5.
_Distribution._--Southeastern Washington south of the Snake River,
the area on the north side of the Columbia River in Klickitat
County, and the Yakima Valley area as far north as the Vantage,
Kittitas County (W. W. D.). Other marginal records are: Kennewick
(W. W. D.), Atilla (W. W. D.) and Walla Walla (E. S. B.).
_Remarks._--Dichromatism seems to be rather common in _Perognathus
p. parvus_--so common that Osgood (1900: 35) recognized both a
"red" and a "gray" phase. Anderson (1932: 102) found no
dichromatism in _P. p. lordi_ in British Columbia. A single
specimen from the Grand Coulee at Dry Falls, Grant County, does
show dichromatism. It is even more red than the reddest topotypes
of _parvus_ examined.
Seemingly the recessive gene for red is still present in _lordi_,
or has mutated anew. When present, the color is deeper and brighter
than in the parent population, in keeping with the heavier
pigmentation of the race _lordi_.
=Perognathus parvus lordi= (Gray)
_Abromys lordi_ Gray, Proc. Zoöl. Soc. London, p. 202, 1868.
_Perognathus lordi_ Merriam, N. Amer. Fauna, 1:28, October 25,
1889.
_Perognathus lordi lordi_ Miller, U. S. Nat. Mus. Bull., 128:279,
April 29, 1924.
_Perognathus parvus lordi_ Davis, Recent Mamm. of Idaho, p. 266,
Caxton Printers, Caldwell, Idaho, April 5, 1939.
_Type._--Obtained in southern British Columbia (probably near Lake
Osoyoos) by J. K. Lord, probably in 1860.
_Racial characters._--Size large; color of upper parts
buffy-olive, washed with blackish; sides buff-olive; facial
markings absent or, if present, indistinct and pale olive; tail
blackish above, olive below.
_Measurements._--Twenty-nine males and 10 females average,
respectively: total length 175, 171; length of tail 93, 89; hind
foot 23.4, 22.9; ear 5.3, 5.1.
_Distribution._--Okanogan Valley and the Columbian Plateau, except
for the southwestern part. Marginal localities are: Vantage, Grant
County (W. W. D.), 10 mi. S. Moses Lake (W. W. D.), Washtucna (M.
V. Z.) and Pullman (M. V. Z.).
_Remarks._--There are constant differences between _Perognathus parvus
parvus_ and _Perognathus parvus lordi_. The latter is larger, darker,
and differs slightly in average cranial measurements. The Snake River,
the Columbia River, and the Wenatchee Mountains separate the geographic
ranges of the two subspecies and prevent intergradation between them.
Nevertheless their close similarity and probable common origin indicate
that both belong to one species, namely _parvus_.
=Perognathus parvus columbianus= Merriam
_Perognathus columbianus_ Merriam, Proc. Acad. Nat. Sci.
Philadelphia, p. 263, September 27, 1894.
_Perognathus lordi columbianus_, Osgood, N. Amer. Fauna, 18:40,
September 20, 1900.
_Type._--Obtained at Pasco, Franklin County, Washington, by Clark
P. Streator on May 9, 1891; type in United States National Museum.
_Racial characters._--Size and color as in _lordi_ but skull
considerably wider in mastoid region.
_Measurements._--Twenty-one male and 9 female topotypes average,
respectively: total length 173, 168; length of tail 91, 89; hind
foot 23.9, 22.8; ear 5, 5.
_Distribution._--The vicinity of the type locality and the part of
the Columbian Plateau north of the Snake and east of the Columbia
rivers.
_Remarks._--This race is separated from _parvus_ by river barriers and
the two do not intergrade. It differs significantly from _lordi_ only in
the wider mastoid region. No barrier separates the range of _lordi_ from
that of _parvus_, and the two races intergrade over a wide area (north
to Moses Lake, east to Washtucna). The race _columbianus_ must have
originated _in situ_ from _lordi_. The habitat of _columbianus_ seems
not to differ from that of _parvus_ or _lordi_.
=Dipodomys ordii columbianus= (Merriam)
Ord kangaroo rat
_Perodipus ordi columbianus_ Merriam, Proc. Biol. Soc. Washington,
9:115, June 21, 1894.
_Dipodomys ordii columbianus_ Grinnell, Jour. Mamm., 2:96, May 2,
1921.
_Type._--Obtained at Umatilla, Umatilla County, Oregon, by C. P.
Streator on October 18, 1890; type in United States National
Museum.
_Measurements._--Fourteen males and 9 females from Walla Walla
County average, respectively: total length 261.5, 248.4; length of
tail 137.2, 139.1; hind foot 40.6, 40.8; ear 13.1, 13.0; weight
52.1, 49.0 grams.
_Distribution._--Western Walla Walla County from the Oregon
boundary north to the Snake River and on Blalock Island in the
Columbia River, Benton County.
[Illustration: FIG. 94. Distribution of the Ord kangaroo rat,
_Dipodomys ordii columbianus_, in Washington.]
_Description._--The kangaroo rat with a body about the size of that of a
chipmunk has an exceptionally large head and large, black eyes. The
forelegs and forefeet are tiny but the hind feet and legs are large and
powerful. The hind foot is almost a third as long as the head and body.
The tail is long, longer than the head and body. Kangaroo rats possess
fur-lined, external cheek pouches, like those of the pocket mice. The
upper parts are soft buff in color. The underparts and a stripe on each
flank are white. The tail is dusky above and below, with white sides; it
is tufted at the tip.
Kangaroo rats are typical of the desert regions of the southwestern
United States, where numerous species and subspecies are found. A single
subspecies of the wide-ranging species _ordii_ occurs into southeastern
Washington, where it is restricted to sandy areas in the Upper Sonoran
Life-zone. In the soft, drifted sand along the Columbia River where
sagebrush and other desert shrubs are low and widely spaced kangaroo
rats are abundant.
These rats are strictly nocturnal. When individuals are dug from their
burrows in the daytime they usually hop about in a dazed manner and
appear to be blinded by sunlight. Near Wallula, Walla Walla County,
these rats were caught at night with a butterfly net as they stood
"paralyzed" in the beam of a powerful searchlight. Such night hunting
was unsuccessful on cloudy or windy nights when kangaroo rats seem not
to move about.
As might be guessed from their powerful hind legs, kangaroo rats travel
in bounds. Near Wallula, where we watched them in their natural habitat,
they traveled, when unfrightened, in slow hops, each hop followed by a
pause. As they struck the surface of the ground an audible thud could be
heard for a distance of several feet. After each jump they paused for a
second or so, perhaps to allow a pursuing enemy to over-run them.
Near Wallula the burrows of kangaroo rats were dug in large mounds of
wind-blown sand. The burrows entered these natural mounds horizontally
and branched two or three times. Their average length was about five
feet. No nests or food stores were discovered although several kangaroo
rats were caught as they burst from entrances at sides of the mounds.
All entrances to burrows were plugged with soft sand. The air in the
burrows seemed warm and humid.
Food found in the cheek pouches of kangaroo rats from Washington
included the seeds of desert annuals, short sections of sprouts of an
unidentified plant, grass seeds, and the leaves of the hop-sage.
A female taken March 22, 1939, contained 3 embryos.
=Thomomys talpoides= (Richardson)
Northern pocket gopher