MAMMALS OF WASHINGTON
BY
WALTER W. DALQUEST
University of Kansas Publications
Museum of Natural History
Vol. 2, pp. 1-444, 140 figures in text
April 9, 1948
UNIVERSITY OF KANSAS
LAWRENCE
1948
(7)
MAMMALS OF WASHINGTON
[Illustration: Mount Rainier from Indian Henry's Hunting Ground, July,
1934. (Fish and Wildlife Service photo by Victor B.
Scheffer. No. 864.)]
MAMMALS OF WASHINGTON
BY
WALTER W. DALQUEST
(Contribution from the Museum of Natural History, University of Kansas)
University of Kansas Publications
Museum of Natural History
Volume 2, pp. 1-444, 140 figures in text
APRIL 9, 1948
UNIVERSITY OF KANSAS
LAWRENCE
1948
UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY
Editors: E. Raymond Hall and Donald F. Hoffmeister
Volume 2, pp. 1-444. 140 figures in text
April 9, 1948
UNIVERSITY OF KANSAS
Lawrence, Kansas
Printed by
Ferd Voiland Jr., State Printer
Topeka, Kansas
1948
[Illustration: decoration]
21-1993
CONTENTS
PAGE
INTRODUCTION 13
PHYSIOGRAPHIC PROVINCES OF THE STATE 16
DISTRIBUTIONAL AREAS 20
CLIMATE AND VEGETATION 25
LIFE-ZONES AND ECOLOGY 32
GEOLOGIC HISTORY OF WASHINGTON 46
THE FAUNAS 52
SPECULATION AS TO EMIGRATIONAL HISTORY OF THE MAMMALS 54
SPECULATION AS TO THE LATER DISTRIBUTIONAL HISTORY OF THE
MAMMALS 68
EXPLANATION OF TREATMENT 110
CHECK LIST OF MAMMALS 112
ACCOUNTS OF SPECIES AND SUBSPECIES 121
ADDENDA 416
BIBLIOGRAPHY 417
INDEX 430
ILLUSTRATIONS
TOPOGRAPHY
FIGURE PAGE
Mount Rainier from Indian Henrys _frontispiece_
1. Cascade Mountains at Canadian Boundary 17
2. Columbia River one mile south of Kellers Ferry 19
4. Cascade Mountains in Chelan National Forest 21
5. Mount Rainier, Yakima Park 22
6. Columbia River in Stevens County 23
7. Blue Mountains, Washington 24
8. North Side of Mount Rainier 26
9. Mount Rainier: Cowlitz Chimneys 28
10. A "pothole" crowded by drifting sand 30
12. Arctic-Alpine Life-zone on Mount Rainier 33
13. Humid subdivision of the Transition Life-zone 34
14. Timbered, arid subdivision of the Transition Life-zone 35
15. Upper Sonoran Life-zone 37
16. Canadian Life-zone 38
18. McDowell Lake. Little Pend Oreille Wildlife Refuge 50
19. Pend Oreille River near Newport 59
20. Rocky bluff along north bank of the Columbia River 65
MAMMALS
FIGURE PAGE
21. Gibbs shrew-mole 122
23. Coast mole and Townsend mole 125
25. Coast mole 128
41. Long-eared bat: female with young 161
42. Boulder Cave: habitat of long-eared bats 162
48. Female black bear and two cubs 171
49. Black bear in "hibernation" 173
54. Fisher 187
59. Wolverine 202
60. Wolverine: dried pelt 203
62. River otter 208
66. Badger 220
69. Coyote 226
72. Cougar or mountain lion: skin 234
73. Cougar or mountain lion: pelts 235
75. Canadian lynx 238
76. Trapper's catch of nine Canadian lynx 239
78. Bobcat 241
82. Townsend chipmunk 260
87. Golden-mantled ground squirrel 282
89. Feeding station of Douglas squirrel 287
91. Northern flying squirrel 292
95. Northern pocket gopher 302
96. Giant mounds formed by pocket gophers 304
97. Food cache of northern pocket gopher 306
99. Beaver 315
100. Beaver lodge and pond 316
101. Cottonwood pole carved by beaver 317
102. Road flooded by beavers 320
106. Deer mouse 327
112. Pennsylvania meadow mouse 345
115. Runways of Townsend meadow mice 350
119. Muskrat 360
121. Mountain beaver 366
123. Big jumping mouse in hibernation 370
130. Elk 392
131. Group of elk 393
132. White-tailed deer 395
133. White-tailed deer: fawn 396
134. Left antler of white-tailed deer 397
135. Antlers of white-tailed deer 398
136. Mule deer 400
137. Black-tailed deer 401
138. Mountain goat 407
139. Group of mountain goats 408
DISTRIBUTION MAPS
3. Mammalian distributional areas 20
11. Life-zones of Washington 32
17. Extent of Vashon-Wisconsin ice 48
22. Gibbs shrew-mole 123
24. Townsend mole 127
26. Coast mole 129
27. Cinereous shrew 133
28. Merriam shrew and Trowbridge shrew 134
29. Wandering shrew 137
30. Dusky shrew 140
31. Mountain water shrew 141
32. Bendire water shrew and pigmy shrew 143
33. Big myotis 147
34. Yuma myotis 149
35. Fringe-tailed myotis and Keen myotis 150
36. Long-eared myotis 152
37. Hairy-winged myotis 155
38. California myotis 156
39. Small-footed myotis 157
40. Silver-haired bat 160
43. Long-eared bat 163
44. Western pipistrelle 164
45. Big-brown bat 166
46. Hoary bat 168
47. Pallid bat 170
50. Black bear 175
51. Grizzly bears 177
52. Raccoon 181
53. Western marten 185
55. Fisher 188
56. Ermine 192
57. Long-tailed weasel 196
58. Mink 199
61. Wolverine 204
63. River otter 209
64. Civet cat 214
65. Striped skunk 218
67. Badger 221
68. Red fox 225
70. Coyote 230
71. Wolf 232
74. Cougar 236
77. Canadian lynx 240
79. Bobcat 243
80. Least chipmunk 252
81. Yellow-pine chipmunk 256
83. Townsend chipmunk 261
84A. Marmots 266
84B. Townsend and Washington ground squirrels 268
85. Columbian and Beechey ground squirrels 274
86. Golden-mantled ground squirrels 280
88. Western gray squirrel 284
90. Red and Douglas squirrels 289
92. Northern flying squirrel 294
93. Great Basin pocket mouse 298
94. Ord kangaroo rat 300
98. Northern pocket gopher 308
103. Beaver 321
104. Northern grasshopper mouse 323
105. Western harvest mouse 325
107. Deer mouse 329
108. Bushy-tailed wood rat 335
109. Northern lemming mouse 337
110. Heather vole 339
111. Gapper and California red-backed mice 342
113. Pennsylvania meadow mouse 346
114. Montane and Townsend meadow mice 348
116. Long-tailed meadow mouse 352
117. Water rat 356
118. Creeping mouse 357
120. Muskrat 362
122. Mountain beaver 368
124. Big jumping mouse 372
125. Porcupine 375
126. Pika 378
127. Snowshoe rabbit 383
128. Black-tailed jack rabbit 386
129. Nuttall cottontail 388
INTRODUCTION
Mammals of Washington are of especial interest to the naturalist
because many of them are recent immigrants; much of Washington was
buried under thick glacial ice until relatively recently and many of
the mammals, therefore, have inhabited the area only since the ice
disappeared. The evolution or development of certain subspecies, in
Washington, has certainly occurred within the last few thousand years.
To be able thus to date such evolutionary changes as have occurred is
of course a matter both of importance and interest to zoölogists. The
evolutionary changes in several species are relatively great. In color,
for example, the bobcat in the humid coastal area of western Washington
is notable for its dark coloration, whereas in the more arid area
of southeastern Washington it is remarkably pale and of a different
subspecies. Within the limits of the state of Washington, elevations
ranging from sea level to more than 14,000 feet occur. Since different
elevations have their characteristic mammals, more kinds are found in
Washington than in other areas of corresponding size that lack such
topographic diversity. Expressed in terms of the life-zone concept,
Washington includes faunas ranging from the Upper Sonoran Life-zone to
those of the Arctic-Alpine Life-zone.
The basis for a study of the mammals of Washington was laid in 1929
by W. P. Taylor and W. T. Shaw in the "Provisional List of the Land
Mammals of the state of Washington." Bailey's "Mammals and Life Zones
of Oregon" and "The Recent Mammals of Idaho" by W. B. Davis deal
with the habits and distribution of mammals in the areas bordering
Washington on the south and east, and were very useful in the
organization of the present report.
The study was first planned from the taxonomic and ecologic point of
view. Such a study, of necessity, involves the classification and
distribution of the forms concerned. Classification has required more
work than any other part of the study and has been, in a sense, the
nucleus of the study. Nevertheless, as the report began to take form
it was recognized that the part dealing with classification and other
purely technical aspects of the paper probably would be uninteresting
to the average reader. Therefore it was felt that a greater impetus
to the study of the mammals of Washington would be given by reducing
the taxonomic accounts to the minimum and dealing principally with the
problems of distribution.
As originally planned, the present report was to be of joint authorship
by Dr. Victor B. Scheffer of the United States Fish and Wildlife
Service, Seattle, and the writer. The press of other work prevented
Dr. Scheffer from devoting as much time as he had planned to the
project. He has, however, contributed his field notes, specimens, and
photographs, and in many other ways assisted in the project.
Field work on mammals of Washington was carried out by the writer
from 1936 to 1940 but a decision to prepare a complete report was
not reached until 1938. Intensive field work was done between 1938
and 1940. In August, 1941, the author took up residence at Berkeley,
California. Drafting of the manuscript was begun at that time as a
student under Professor E. Raymond Hall. War conditions and the press
of other work delayed completion. Subsequently, the manuscript was put
in final form at the University of Kansas.
Many persons in addition to Dr. Scheffer have given assistance in the
course of this work. Dr. E. Raymond Hall, in particular, encouraged
the project and gave assistance in various ways including critical
attention to the manuscript. I am indebted also to Dr. Trevor Kincaid
and Mrs. Martha Flahaut of the University of Washington, Dr. Seth B.
Benson and Dr. Alden H. Miller of the University of California, Dr. H.
H. T. Jackson of the U. S. Fish and Wildlife Service, Dr. George E.
Hudson of the Charles R. Conner Museum, Mr. Burton Lauckhart of the
State of Washington Department of Game, and Mr. Ernest Booth of Walla
Walla College. Mrs. Peggy B. Dalquest typed and edited the several
preliminary drafts of the manuscript and aided in the laboratory
and field work. Thanks are due also to many others, including game
protectors, hunters and trappers, who have given assistance. The names
of some of them are mentioned in the following pages.
Approximately ten thousand specimens of mammals were used. In
decreasing order, according to the number of specimens studied from
Washington, the following collections are to be mentioned: materials
obtained principally from southern Washington in the years 1939 to
1942 as a result of the interest of Miss Annie M. Alexander and Dr.
E. Raymond Hall; these materials are in the University of California
Museum of Vertebrate Zoölogy. The writer's own collection which at
one time numbered 2,500 specimens was the second source. The residue,
the part not destroyed by fire at the writer's home in the spring of
1942, in Seattle, now is in the Museum of Vertebrate Zoölogy at the
University of California and the Museum of Natural History at the
University of Kansas. The other collections are those of the Biological
Surveys of the United States Fish and Wildlife Service, the Washington
State Museum at Seattle, the Charles R. Conner Museum at Washington
State College, and the Museum of Natural History at the University of
Kansas. In the latter collection are some materials obtained nearly
half a century ago by the late L. L. Dyche, some recently taken
specimens added by reason of the provision for work of this kind by
the University of Kansas Endowment Association and, as noted above,
a part of the author's original collection. Selected specimens from
several other collections have been used and these are indicated in
the text when particular reference is made to the specimens. Most of
the specimens studied were conventional study skins with skulls. In
some instances skeletons, skins alone, skulls alone, or entire animals
preserved in alcohol have been used.
PHYSIOGRAPHIC PROVINCES OF THE STATE
The state of Washington was divided into seven physiographic provinces
by Culver (1936). Culver points out that the physiography, though
complicated in detail, is basically simple.
The state, including Puget Sound and other inland waters, is nearly
rectangular in shape and is 69,127 square miles in area. Its western
boundary is the Pacific Ocean. Politically, it is bounded on the north
by the United States-Canadian Boundary (49° north lat.), on the east by
the state of Idaho, and on the south by the state of Oregon.
The Cascade Mountain Range, or Cascade Mountains Province, runs
from the northern to the southern boundary and divides the state
into two sections, of which the eastern is slightly the larger. The
mountain range trends approximately 10° east of north and continues
uninterruptedly into British Columbia, but on the south the Columbia
River separates the Washington Cascades from the Cascades of Oregon.
Near the northern border of the state the range is wide, extending
from the Mount Baker Range on the west to Mount Chopaka, 100 miles to
the east. In the central part of the state it is more compact, being
some 60 miles wide in the vicinity of Mount Rainier. Farther south it
expands to approximately 100 miles.
The Cascades of Washington possess five great volcanic cones. These are
Mount Baker (10,750 feet elevation) on the north, Glacier Peak (10,436
feet) in the north-central part, Mount Rainier (14,408 feet) in the
central area, and Mount Adams (12,326 feet) and Mount St. Helens (9,697
feet) on the south. Excluding these volcanic peaks, the crests of the
Cascades have a relatively uniform level descending from an average
of 8,000 feet at the north to 5,000 feet at the south. Ranges jutting
southeastwardly from the north-central Cascades parallel elongate
intermontane valleys. These include the Entiat and Wenatchee mountains.
The latter range reaches the Columbia River and forms an important
barrier to mammalian movements.
There is an extensive area of anticlinal ridges extending from the
southern Cascades to the Columbia River. This area includes the Horse
Heaven and other hills. Most of it is drained by the Yakima River and
is termed, in this report, the Yakima Valley Area.
[Illustration: FIG. 1. Cascade Mountains at Canadian boundary, looking
west along boundary trail. Monument 100 in foreground, headwaters of
Ashnola River in broad valley at right. (Forest Service photo, No.
4328.)]
The Puget Sound Trough, or Puget Sound Province, is immediately west
of and parallel to the Cascade Mountains. It is part of a structural
downwarp that extends southward into Oregon. Most of the area is
below 1,000 feet elevation, and much of the northern part is below
sea level and therefore flooded by the marine waters of Puget Sound.
The most prominent feature of this area is Puget Sound. This is a
glacially-carved and drowned river valley, studded with islands,
peninsulas, fjords and bays that all possess a general north-south
orientation resulting from the direction of ice movement. Puget Sound
is connected with the Pacific Ocean by the Strait of Juan De Fuca, a
wide channel separating the state of Washington and Vancouver Island.
The San Juan Islands represent the glaciated remnants of mountains
that, in preglacial time, may have connected the mountains on Vancouver
Island with the Cascades of Washington. The San Juan Islands lie at the
junction of Puget Sound, the Strait of Georgia, and the Strait of Juan
De Fuca. As a result of a boundary dispute and subsequent arbitration,
the islands were apportioned, on the basis of the deepest channel
separating them, between Canada and the United States. The American
portion includes more than 400 islands. These vary in size from mere
rocks above high tide to Orcas Island, 60 square miles in area.
The Olympic Peninsula, or Olympic Province, lies between Puget Sound
and the Pacific Ocean. The Strait of Juan De Fuca separates this
peninsula from Vancouver Island on the north. In the south the valley
of the Chehalis River is a convenient boundary for the province. The
central portion of the peninsula is occupied by the Olympic Mountain
Range. This range is nearly oblong in shape, measuring some 70 miles
east to west by 45 miles north to south. The mountains are extremely
rough and jagged. They rise from sea level to above 6,000 feet. The
highest peak, Mount Olympus, is 8,150 feet in elevation.
South of the Olympic Province and west of the Puget Sound Trough is an
area of low, rough hills. Culver called it the Willapa Hills Province.
The northern third of the land east of the Cascade Mountains, or
northeastern Washington, is termed the Okanogan Highland Province by
Culver. Its southern boundary is set at the east-west flow of the
Spokane and Columbia rivers. The outstanding physiographic feature of
this area is its division into north-south trending areas of lowland
with intervening highlands and mountain ranges. The rivers are, from
east to west, the Clark Fork, Colville, Columbia, Kettle, San Poil and
Okanogan. Not all intervening highlands are separately designated as
mountains. Among these named are the Pend Oreille, Huckleberry, Kettle
River, and Okanogan ranges.
The part of eastern Washington south of the Okanogan Highland Province,
save the extreme southeastern corner of the state, constitutes the
Columbia Lava Province. This is an extensive, relatively level plateau
that lies mainly below 2,000 feet elevation. The plateau consists of
gently folded lava flows that reach a depth of 4,000 feet in some
places (Russell, 1893) and slope inward from the east, north, and,
in part, the west (Flint, 1938). These horizontal layers of basalt
are extremely resistant to erosion by other than large rivers. Two
great gashes cross the Plateau diagonally from the northeast to the
southwest; these are Moses Coulee and the Grand Coulee. These old
coulees are the former valleys of the Columbia River, and were formed
at the time when the course of the river was successively blocked by
the advance of Pleistocene ice. The Snake River crosses the southern
edge of the Columbia Lava Province and separates the plateau proper
from an area of similar land to the southward.
[Illustration: FIG. 2. Columbia River one mile west of Kellers Ferry,
Washington, elevation 1,060 feet, April 16, 1940. (Fish and Wildlife
Service photo by Victor B. Scheffer, No. 933.)]
The Blue Mountains Province is an area of relatively small extent in
the extreme southeastern corner of the state of Washington. There, the
province concerned constitutes, as it were, a northward extension of
the Blue Mountains of Oregon. The mountains rise to only 5,000 feet
elevation in the Washington part of the Blue Mountains Province.
DISTRIBUTIONAL AREAS
The physiographic provinces are areas of land form. The form of the
land has a considerable effect on the temperature, humidity, drainage,
weathering, soil, and other non-organic features that combine to
produce the various life-zones and influence the distribution of
mammals. One might therefore expect a close correlation of mammalian
distributional areas with physiographic provinces. Although there is
a correlation, it is not exact because the distribution of mammals is
influenced also by certain other factors. Among these are historical
factors and isolation by geographic barriers.
[Illustration: FIG. 3. Mammalian distributional areas of Washington.
A. Western Washington. B. Cascade Mountains. C. Northeastern
Washington. D. Blue Mountains. E. Southeastern Washington.
F. Yakima Valley. G. Columbian Plateau.]
The Cascade Mountains Province of Culver includes the Yakima Valley
Area. This province contains two completely different mammalian
distributional areas. The higher mountains possess a boreal, alpine
fauna; the Cascade Range itself is called the Cascade Area in this
report. The Yakima Valley Area possesses a desert fauna derived from
the desert of eastern Oregon.
The land west of the Cascades is separated into three physiographic
provinces, the Puget Sound, Willapa Hills, and Olympic Mountains
Province. The differences between the mammalian faunas of the Puget
Sound and Willapa Hills provinces are slight. The Olympic Mountains
possess a few species not found in the lower areas. The similarities of
the faunas of the three provinces far outnumber their differences, and
it seems best to consider them subdivisions of one distributional area.
[Illustration: FIG. 4. Cascade Mountains in Chelan National Forest,
looking southwest at Straight Ridge; Cataract Creek (Methow watershed)
at left. (Forest Service photo. No. 4260.)]
The Okanogan Highland Province extends, from a physiographic point
of view, west of the Okanogan River Valley. This valley, however, is
a fairly efficient barrier to mammals. Thus the part of the state
east of the Okanogan Valley and north of the east-west flow of the
Spokane and Columbia rivers may be called the Northeastern Washington
Distributional Area.
The Columbia Lava Province includes the land both north and south of
the Snake River. Since the Snake River serves as a barrier to some
species, it seems better to term the area north of the Snake River
the Columbian Plateau Area and that to the south the Southeastern
Washington Distributional Area.
The Blue Mountains Province and the Blue Mountains Distributional Area
are the same.
[Illustration: FIG. 5. Yakima Park (or Sunrise Park), elevation 6,000
feet, Mount Rainier, August 29, 1932. (Photo by 116th Photo Section,
Washington National Guard, No. 014-36A-116.)]
[Illustration: FIG. 6. Columbia River at Hunters Ferry, Stevens County,
Washington, April 15, 1940. (Fish and Wildlife Service photo by Victor
B. Scheffer. No. 932.)]
[Illustration: FIG. 7. Blue Mountains, Umatilla National Forest,
Washington, looking north-northeast across Al Williams Ridge to
Tucannon River; 1933. (Forest Service photo, No. 4437.)]
PHYSIOGRAPHIC PROVINCES DISTRIBUTIONAL AREAS
Cascade Mountains { Cascade Mountains
{ Yakima Valley
Puget Sound }
Willapa Hills } Western Washington
Olympic Mountains }
Okanogan Highlands Northeastern Washington
Columbia Lava { Columbian Plateau
{ Southeastern Washington
Blue Mountains Blue Mountains
CLIMATE AND VEGETATION
The life-zone theory of plant and animal distribution was proposed by
Merriam (1892). Merriam's life-zones have been severely criticized by
many authors, especially because an error was made in computing some of
the data on temperature. However, zonation of vegetation and animals is
obvious in Washington, and the life-zone concept has been employed in
Washington by numerous botanists and zoölogists. Among them are: Piper
(1906), Taylor and Shaw (1927), Jones (1936, 1938) and St. John (1937).
The higher parts of the Cascade Mountains are in the Arctic-alpine
Life-zone. This is the area of wind-swept ridges, living glaciers, and
permanent snow fields.
Trees are absent but a few shrubs are present; these include: _Juniperus
sibirica_, _Salix cascadensis_, _Salix nivalis_, _Gaultheria humifusa_,
_Empetrum nigrum_, and the heathers, _Phyllodoce glanduliflora_,
_Cassiope mertensiana_ and _Cassiope stelleriana_. Jones (1938) lists a
total of 98 species of plants from the Arctic-alpine Life-zone of Mount
Rainier. Many of these plants are most abundant in the next life-zone
lower, and are of but incidental occurrence in the Arctic-alpine
Life-zone. No mammalian species is resident but individuals of several
species regularly visit and occasionally breed there.
Below the Arctic-alpine the Hudsonian Life-zone stretches the entire
length of the Cascades. Temperatures are low, especially in winter;
then the thermometer does not rise above zero for weeks at a time.
The average annual temperature at Paradise, 5500 feet, Mt. Rainier,
is 38.6° (all temperatures given here are in degrees Fahrenheit).
Snowfall is heavy. The average yearly snowfall, for four years, at
Mt. Baker Lodge, at 4200 feet elevation, Whatcom County, was 478
inches; at Goat Lake, 2900 feet, Snohomish County, 261 inches; Tye,
Stevens Pass, 3010 feet, King County, 398 inches; Paradise, 5500 feet,
Mt. Rainier, 587 inches. The deepest snow recorded at Paradise was
27 feet, 2 inches on April 2, 1917. Following the spring thaws the
mountain passes are opened to travel, usually in April or May, although
nightly temperatures in April and May are still below zero. Spring
precipitation is heavy, the monthly average for a twelve-year period
at Paradise being 6.78 inches in April and 5.5 inches in May. Summer
temperatures are high in the daytime, when the sun beats down through
the rarefied atmosphere, but cool at night when accumulated heat is
lost through the thin atmospheric blanket. In summer precipitation is
light, averaging, at Paradise, 3.46 inches in June, .9 inches in July,
and 3.44 inches in August. In the autumn the temperature, both daily
and nightly, drops somewhat, and rain and cloudiness are the rule. At
Paradise the average precipitation in September is 8.29 inches and in
October 10.02 inches. The winter snows usually arrive by the middle of
November.
Trees that are characteristic of parts of the Hudsonian Life-zone
include the alpine fir (_Abies lasiocarpa_), mountain hemlock (_Tsuga
mertensiana_), Alaska cedar (_Chamaecyparis nootkatensis_) and
white-barked pine (_Pinus albicaulis_). The following shrubs are listed
by Jones (1938) as common in the Hudsonian Life-zone on Mt. Rainier:
_Salix barclayi_, _Salix commutata_, _Juniperus sibirica_, _Alnus
sinuata_, _Ribes howellii_, _Lutkea pectinata_, _Potentilla fruticosa_,
_Sorbus occidentalis_, _Spiraea densiflora_, _Pachistima myrsinites_,
_Arctostaphylos nevadensis_, _Arctostaphylos uva-ursi_, _Cassiope
mertensiana_, _Cassiope stelleriana_, _Phyllodoce empetriformis_,
_Rhododendron albiflorum_ and _Gaultheria ovalifolia_.
[Illustration: FIG. 8. North side of Mount Rainier, 14,408 feet, with
Mount Adams at left and Mount St. Helens at right. June 19, 1932.
(Photo by 116th Photo Section, Washington National Guard, No.
011-36A-116.)]
There are extensive coniferous forests in the Canadian Life-zone, still
lower on the mountain slopes. This is an area of lesser temperature
extremes than is the Hudsonian Life-zone. The average annual
temperature at Longmire, 2761 feet, Mt. Rainier, is 43.8°. The average
temperature for the winter months, however, is below freezing. In July
and August the temperatures are high, especially in the daytime. The
eighteen year average for Longmire during these months is 60.6°. Snow
is regular but the fall is lighter than in the Hudsonian Life-zone. The
annual average, over a period of nineteen years, is 184.4 inches at
Longmire. Precipitation is similar to that in the Hudsonian Life-zone,
averaging perhaps slightly less.
In the Cascades the typical feature of the Canadian Life-zone is
the extensive coniferous forest that extends, almost without a
break, the entire length of the Cascades on both sides of the main
crest. In addition to Douglas fir, the following trees occur in
this forest: western hemlock (_Tsuga heterophylla_), amabalis fir
(_Abies amabalis_), white pine (_Pinus monticola_) and noble fir
(_Abies nobilis_). Other plants include _Vaccinnium ovalifolium_,
_Vaccinnium membranaceum_, _Menziesia ferruginea_, _Alnus sinuata_,
_Acer circinatum_, _Sorbus cascadensis_, _Cornus canadensis_,
_Clintonia uniflora_, _Stenauthium occidentale_, _Galium oreganum_,
and _Prenanthes lessingii_. Saprophytes abundant in, if not confined
to, this zone are listed by Jones as: _Monotropa uniflora_, _Monotropa
hypopitys_, _Allotropa virguta_, _Newberrya congesta_, _Pterospora
andromedea_, _Corallorrhiza maculata_, _Corallorrhiza mertensiana_ and
_Corallorrhiza striata_.
West of the Canadian Life-zone in the western Cascades, the coniferous
forests merge with the lowland forests of western Washington. To the
east of the Canadian Life-zone in the eastern Cascades, there is a
distinct change to a more arid climate and flora. At Leavenworth, 1167
feet, Chelan County, the annual average precipitation is but 19.5
inches and at Cle Elum, 1930 feet, but 23.23 inches. Temperatures are
higher, the annual average of the above two localities being 47.2°
and 45.4° respectively. The winter months are cold, with the average
temperature in January and February below freezing. In summer the
averages in July and August at Leavenworth are 68.8° and 68.0°, with
the average maximum being 87.5° and 86.1°. Snowfall is heavy, the
yearly average at Leavenworth being 98.5 inches and at Cle Elum 86.3
inches. The effect of this more arid climate is seen in the vegetation.
The dense Douglas fir forest, is replaced by more open forests of
yellow pine (_Pinus ponderosus_). Groves of oak (_Quercus garryana_)
are found near streams. The open forests give way to the extensive
grasslands bordering the desert. The transition of vegetation is
similar to that occurring in the Yakima Valley Area.
In the Yakima Valley Area, arid conditions prevail. The average yearly
precipitation at Yakima is 6.67 inches. Only in November, December and
January may more than one inch of precipitation be expected monthly.
Snow may be expected in the winter months and the yearly average
snowfall is 22.1 inches. Winter temperatures are low, the average
for December and January being but slightly above freezing. Summer
temperatures are extreme; the July average is 73.1° and the average
maximum for the same month is 89°. The highest temperature recorded is
111°.
The open pine forests of the eastern Cascades give way to grasslands.
Grasses of several species are common but the bunchgrass (_Agropyron
spicatum_) is most important. Other plants include the primrose
(_Oenothera pallida_), lupines (_Lupinus_), and _Mertensia_. In
ravines and near watercourses such shrubs as hawthorn (_Crataegus
douglasii_), service-berry (_Amelanchier cusickii_, _Amelanchier
utahensis_), aspen (_Populus tremuloides_), syringa (_Philadelphus
lewisii_), snowberry (_Symphoricarpos albus_), choke-berry (_Prunus
melanocarpa_) and elderberry (_Sambucus caerulae_) form thickets.
Lower in the valley the vegetation is xerophytic, similar to that
of the Columbian Plateau. Sagebrush (_Artemisiae tridentata_) is
dominant. Other shrubs include rabbit brush (_Chrysothamnus nauseosus_,
_Chrysothamnus viscidiflorus_), hop sage (_Grayia spinosa_), black sage
(_Purshia tridentata_) and greasewood (_Sarcobatus vermiculatus_).
[Illustration: FIG. 9. Mount Rainier. Washington: Cowlitz Chimneys
from base of Dege Peak, July 19, 1933. (Fish and Wildlife Service
photo by Victor B. Scheffer, No. 859.)]
Climatic conditions in the Olympic Mountains are, in general, similar
to those of the higher Cascade Mountains. There is a limited area of
Arctic-alpine Life-zone on Mount Olympus. The principal life-zone is
the Hudsonian. The Canadian merges with the lowland Humid-Transition
and is difficult to ascertain as a separate zone. In the Hudsonian
Life-zone the average temperatures are low. Winter climate is bitter
and the snow lies deep. In the absence of government weather stations
in the Olympics, detailed descriptions of climatic conditions can
not be given. Vegetation of the Hudsonian Life-zone of the Olympic
Mountains is, in general, similar to that of the same life-zone of the
Cascades (see Jones, 1936, Botanical Survey of the Olympic Peninsula).
The lowlands of western Washington have a cool, humid climate. The
average annual temperature of the area varies little from 50°. In
winter the temperature, especially in January and February, commonly
drops below the freezing point at night. Summer temperatures are
moderate, rarely reaching 90°. Snowfall is light, averaging about 10
inches. The prevailing winds are from the west and are moisture-laden.
They rise over the Olympic Mountains and loose heavy rains along the
coastal area of the lowlands. The average annual precipitation at La
Push, Clallam County, is 97.9 inches; at Clearwater, Jefferson County,
124.98 inches; at Aberdeen, Grays Harbor County, 81.58 inches; at South
Bend, Pacific County, 83.35 inches. In contrast, the more inland areas
receive less than half as much precipitation. The yearly average at
Bellingham is 31.09 inches; at Seattle, 30.07 inches; at Tacoma, 39.53
inches; at Vancouver, Clark County, 37.24 inches.
The outstanding feature of the vegetation of western Washington is the
coniferous forest. Previous to the logging activities a dense cover of
Douglas fir, western hemlock and red cedar spread almost unbroken over
the area. The openings in the forest and the marshy ravines and river
valleys supported growths of underbrush and deciduous trees so dense and
luxuriant as to compare with a tropical jungle. In the dense rain
forests along the coast, mosses and lichens develop an understory
vegetation many inches deep and clothe the branches of the forest trees.
The mild temperature and excessive rainfall cause some species that
usually are of bush or shrub size to reach the proportions of small
trees. In some places one can climb twenty feet from the ground in a
huckleberry tree, the trunk of which is five inches in diameter. The
coniferous forest is made up of several species of trees. Most important
among these are the western hemlock (_Tsuga heterophylla_), Douglas fir
(_Pseudotsuga taxifolia_), and red cedar (_Thuja plicata_). Locally the
western yew (_Taxus brevifolia_), lodgepole pine (_Pinus contorta_) and
spruce (_Picea sitchensis_) may be common. Deciduous trees are numerous
and include several willows (_Salix_ sp.), aspen (_Populus
tremuloides_), hazel (_Corylus californica_), alder (_Alnus oregona_),
oak (_Quercus garryana_), broadleaf maple (_Acer macrophyllum_), vine
maple (_Acer circinatum_), and flowering dogwood (_Cornus nuttallii_).
Mosses and ferns are abundant. The sword fern (_Polystichum munitum_)
and bracken (_Pteridium aquilinum_) are especially common. Space
prevents listing all but a fraction of the typical shrubs but these
include huckleberry (_Vaccinium parvifolium_, _Vaccinium ovatum_),
Oregon grape (_Berberis nervosa_), salal (_Gaultheria shallon_), rose
(_Rosa gymnocarpa_), thimbleberry (_Rubus parviflorus_), salmonberry
(_Rubus spectabilis_), blackcap raspberry (_Rubus leucodermis_) and wild
blackberry (_Rubus macropetalus_).
The higher parts of some of the ranges of northeastern Washington are in
the Hudsonian Life-zone, but most of the mountains are in the Canadian
Life-zone. The valleys are in the Transition Life-zone. Climatic
conditions are similar to those of the eastern slopes of the Cascades.
Winter temperatures are low, the average for December, January and
February being below freezing. Summer temperatures are high, the July
average for Colville being 67.2° and the July average maximum being
87.4°. Vegetation consists principally of coniferous forests in the
mountains and deciduous woods in the valleys. Among the interesting
features of the vegetation are the extensive stands of almost pure larch
(_Larix occidentalis_). In most respects the flora closely resembles
that of the Blue Mountains.
The Blue Mountains of southeastern Washington differ from other ranges
in Washington in their relative aridity. There are few streams and a
single river drains the area. There are no government weather stations
in the Blue Mountains. The winter temperatures are low and the snow deep
and lasting. Summer temperatures are high and humidity and precipitation
low. Coniferous forests of the type of arid regions form the principal
tree cover. Typical plant species include the white fir (_Abies
grandis_), alpine fir (_Abies lasiocarpa_), larch (_Larix
occidentalis_), spruce (_Picea columbiana_), and such shrubs as fool
huckleberry (_Menziesia ferruginea_), _Pachystima myrsinites_, dogwood
(_Cornus canadensis_), wild current (_Ribes petiolare_), mountain
mahogany (_Cercocarpus ledifolius_), spirea (_Spiraea_ sp.), lupines
(_Lupinus_) of several species, maple (_Acer douglasii_), buckbrush
(_Ceanothus sanguineus_), sticky brush (_Ceanothus velutinus_), and
huckleberry (_Vaccinium membranaceum_).
[Illustration: FIG. 10. A "pothole" being crowded by drifting sand,
ten miles south of Moses Lake, Washington, March 23, 1940. (Fish and
Wildlife Service photo by Victor B. Scheffer, No. 925.)]
The Columbian Plateau and southeastern Washington present desert
conditions. At Odessa, 1590 feet, Lincoln County, the average annual
precipitation is only 9.38 inches, and only in the winter may more than
one inch of precipitation per month be expected. The average temperature
is 48.5°. In the winter the average is below freezing but in July it is
71.3°. The average maximum for July is 90° and an extreme of 111° is
recorded. Walla Walla, 991 feet, has a higher annual precipitation
(16.66 inches) but higher temperature (yearly average 53.5°, July
average 75.0°, average July maximum 88.6°, extreme 113°). Winter
temperatures on the Columbian Plateau are low. The January average at
Odessa is 25.3° and at Walla Walla 32.4° The average yearly snowfall at
Odessa is 19.4 inches and at Walla Walla 23.5 inches. Vegetation of the
Columbian Plateau and southeastern Washington is of the desert type. A
few pines and junipers grow in favored places. Along streams the
cottonwood (_Populus hastata_) and willow (_Salix_) of several species
are common. Most typical are grasses and shrubs such as the bunch grass
(_Agropyron inerme_, _Agropyron spictatum_), foxtail (_Alopecurus
aequalis_), cheat grass (_Bromus tectorum_), saltbrush (_Atriplex
truncata_), greasewood (_Sarcobatus vermiculatus_) mustard (_Arabis_
sp., _Brassica_ sp.), sagebrush (_Artemisia rigida_, _Artemisia
tridentata_), rabbit brush (_Chrysothamnus nauseosus_, _Chrysothamnus
viscidiflorus_) and cactus (_Opuntia polyacantha_). The arid climate of
the Columbian Plateau affects, to some extent, surrounding areas. Thus
the Yakima Valley Area, the Columbia Valley, where it borders the
Plateau, and the Okanogan Valley possess vegetation typical of the
Columbia Plateau.
LIFE-ZONES AND ECOLOGY
The Transition Life-zone is the principal life-zone in Washington. It is
divisible into three subdivisions: Humid, Arid-timbered and
Arid-grasslands (Fig. 11) subdivisions. The Humid and Arid-timbered
subdivisions of the Transition life-zone are closely related in some
respects but different in others. They are separated by the Cascade
Mountains. All of the Transition Life-zone west of the Cascades belongs
to the Humid subdivision and the timbered Transition Life-zone east of
the Cascades belongs to the Arid-timbered subdivision.
[Illustration: FIG. 11. Life-zones of Washington. Arctic-alpine not
shaded. A. Hudsonian and Canadian (mapped together). B. Forested
Transition (Humid and Arid subdivisions). C. Arid-grasslands of the
Transition. D. Upper Sonoran.]
The Arid-grasslands are of minor geographic extent. Although this
subdivision is relatively distinct as concerns the distribution of
plants, insects and birds, it is of little importance as concerns the
distribution of mammals. For the most part, the mammals occupying
it are more representative of surrounding areas. Large parts of the
Arid-grasslands have been taken over for agriculture, especially wheat
raising. Perhaps the greatest extent of the Arid-grasslands existing
in a natural state is along the eastern Cascade Mountains and along
the eastern side of the Columbian Plateau. These are truly transition
areas, situated where the arid pine forests are replaced by open,
sagebrush desert.
[Illustration: FIG. 12. Arctic-alpine Life-zone, Mount Rainier,
Washington: Cowlitz Glacier from elevation of 9,500 feet. (Fish and
Wildlife Service photo by Victor B. Scheffer. No. 900.)]
The Upper Sonoran Life-zone includes the desert areas of Washington
(figure 11 D). Its principal extent is the central Columbian Plateau.
From the central Columbian Plateau, fingerlike projections of desert
extend along the principal valleys.
The Arctic-alpine Life-zone occurs in the high Olympic Mountains and on
the higher peaks of the Cascades. This is shown on the life-zone map,
Fig. 11, as white, unshaded areas.
The mammalian faunas of the Hudsonian and Canadian life-zones resemble
each other closely. The boundary between them is too complex to permit
separating them on a small-scale map. Consequently they are mapped
together on Fig. 11 as A.
THE HUMID SUBDIVISION OF THE TRANSITION LIFE-ZONE
This subdivision is remarkably uniform in composition over western
Washington. The greatest difference is in precipitation. Rainfall along
the coast is heavier than that in the interior. Consequently vegetation
is more dense and luxuriant along the coast.
Four habitats may be distinguished in the Humid subdivision and further
subdivision is possible. The dominant and most extensive habitat is the
forest. Dominant mammalian species include: _Peromyscus maniculatus_,
_Sorex trowbridgii_, _Sorex obscurus_, _Tamiasciurus douglasii_,
_Clethrionomys californicus_, _Aplodontia rufa_, _Glaucomys sabrinus_
and _Odocoileus hemionus_. Mammals are scarce and nocturnal forms
prevail. As a rule, a line of mouse traps set in a forest habitat will
take principally _Peromyscus maniculatus_ with a few _Sorex trowbridgii_
and _Sorex obscurus_ and rarely a _Clethrionomys californicus_. In some
places, especially where the moss is deep, a line of mouse traps will
catch only shrews.
[Illustration: FIG. 13. Humid subdivision of the Transition Life-zone,
Headley's Marsh, five miles east of Granite Falls, Washington, June 4,
1938. (Fish and Wildlife Service photo by Victor B. Scheffer, No. 60.)]
A second important habitat is the deciduous jungle. This differs from
the forest habitat in that the dominant trees are of the deciduous type
and in that understory vegetation, such as shrubs and annuals, is dense.
The jungle habitat occurs in ravines and in valleys of streams and
rivers and, in general, covers the lower, poorly drained portions of the
Humid subdivision of the Transition Life-zone. Mammals are abundant and
varied in the jungle habitat. The deer mouse (_Peromyscus maniculatus_)
is the most common mammal but a line of mouse traps might also catch:
_Neurotrichus gibbsii_, _Scapanus orarius_, _Sorex vagrans_, _Microtus
oregoni_, or _Zapus p. trinotatus_. The mountain beaver, snowshoe
rabbit, and Townsend chipmunk also occur there.
The prairies form a third habitat. These areas of native grasslands are
of minor extent but are the principal home of several races of gophers
and the Townsend mole (_Scapanus townsendii_). Deer and elk also browse
on the prairies.
[Illustration: FIG. 14. Timbered arid subdivision of the Transition
Life-zone, Kettle Falls on the Columbia River (now beneath Coulee Dam
backwater), Stevens County, Washington, June 15, 1938. (Fish and
Wildlife Service photo by Victor B. Scheffer, No. 72.)]
A fourth habitat is the marsh. In it there is here included the sphagnum
bogs and marshy shores of lakes and streams. This habitat is
characterized by damp ground, standing water, and dense vegetation.
Typical mammalian species include the water shrew (_Sorex bendirii_),
Townsend meadow mouse, muskrat and mink.
Other habitats, such as aerial for the bats and aquatic for the beaver
and otter, might be listed.
THE ARID TIMBERED SUBDIVISION OF THE TRANSITION LIFE-ZONE
In Washington the Arid timbered subdivision of the Transition Life-zone
is the open, pine forest. Because of the aridity of this habitat,
marshes and streamside thickets are uncommon, but where habitats of this
kind do occur they have a fauna distinct from that of other habitats.
The pine forest habitat includes many diurnal species, such as the red
squirrel, yellow-pine chipmunk, and Columbian ground squirrel. The
white-tailed deer occurs here and, for most of the year, the mule deer.
Snowshoe rabbits are usually present. Near rocks the bushy-tailed wood
rat is common. Mice are scarce, probably because of the open nature of
the surface of the ground. A night's trapping usually yields only a few
_Peromyscus maniculatus_.
The mammalian fauna of the marshes and streamside thickets is similar.
Shrews including _Sorex vagrans_ and _Sorex obscurus_ are uncommon.
Meadow mice, including _Microtus pennsylvanicus_, _Microtus
longicaudus_, and more rarely _Microtus montanus_, are taken.
THE ARID GRASSLANDS SUBDIVISION OF THE TRANSITION LIFE-ZONE
This subdivision is so much utilized by man where it occupies any
considerable areas, and is of such a transitional nature elsewhere, that
it is important for only a few native wild mammals. The sagebrush vole
(_Lagurus curtatus_) seems to be confined to the arid grasslands. The
white-tailed jack rabbit is now found principally in the arid
grasslands, but its confinement there has resulted probably from
competition with the black-tailed jack rabbit. The montane meadow mouse
(_Microtus montanus_) is the only common, representative species. Many
species from the Upper Sonoran Life-zone extend into the arid grasslands
where conditions are suitable. These include _Reithrodontomys
megalotis_, _Perognathus parvus_, _Citellus washingtoni_ and _Marmota
flaviventris_. A few species more typical of the Arid timbered
subdivision of the Transition Life-zone stray onto the arid grasslands.
_Citellus columbianus_ and _Microtus longicaudus_ may be included here.
THE UPPER SONORAN LIFE-ZONE
The sagebrush desert in Washington is relatively uniform in nature.
Several different habitats may be distinguished, such as sandy areas,
open sage, dense sage, stony ground, and talus. Qualitatively, however,
the mammalian fauna of these areas is surprisingly similar.
Quantitatively, there are great differences. For example, the
grasshopper mouse is rare in the open sage areas with hard, claylike
soil but common on drifted sand. The harvest mouse is common in dense
sage but rare in open sage or in open, sandy areas. Mammals are abundant
on the sagebrush desert and typical species include: the black-tailed
jack rabbit, Nuttall cottontail, Ord kangaroo rat, Great Basin pocket
mouse, Townsend ground squirrel, Washington ground squirrel.
Marshes are not uncommon on the Columbian Plateau and elsewhere in the
Upper Sonoran Life-zone in Washington. They do not possess a fauna that
is strictly Upper Sonoran but instead contain species more typical of
the Arid-timbered subdivision of the Transition Life-zone. Meadow mice
found in desert marshes include _Microtus montanus_ and _Microtus
pennsylvanicus_. The only shrew we have found is _Sorex vagrans_. The
harvest mouse (_Reithrodontomys megalotis_) is often abundant in
marshes.
[Illustration: FIG. 15. Upper Sonoran Life-zone, sand and basalt
cliffs along the east bank of the Columbia River, at Vantage,
Washington, 1930. (Fish and Wildlife Service photo by Victor B.
Scheffer, No. 848.)]
THE CANADIAN LIFE-ZONE
The Canadian Life-zone is a relatively uniform area in which the forest
habitat is most important. Talus and swift, cold streams bring some
typical mammalian species into the Canadian Life-zone from the
Hudsonian. Mammals are usually common; they are abundant only in the
upper portion of the Life-zone. Arboreal species and forms adapted to
life beneath the forest cover are dominant. The Douglas squirrel, red
squirrel, northern flying squirrel and Townsend chipmunk are typical
arboreal species. Traps set beneath the trees might catch _Peromyscus
maniculatus_, _Clethrionomys gapperi_, _Neotoma cinerea_, _Sorex
obscurus_, or _Sorex trowbridgii_.