I. ENVIRONMENTAL CONTEXT
A review of the diverse environments and various natural resources of the area now encompassed by Olympic National Park will help set discussions of the aboriginal groups which used the land into a physical context. To that end the report examines the physiography, climate, plant life-zones and culturally meaningful flora and fauna of the Park. The material presented in this section is taken largely from Warren (1982), Tabor (1975), Danner (1955), and Wessen (1978a).
Geography and Physiography
Olympic National Park, with an area of 1420 square miles, is composed of two irregularly shaped, discontiguous portions of land on the Olympic Peninsula of Western Washington (see Figure 1). The first is a narrow strip along the Pacific Ocean, approximately 57 miles in length, extending south from Shi Shi Beach, near Cape Flattery, to the northern boundary of the Quinault Indian Reservation. The second and much larger portion of land consists of about 1380 square miles in the rugged, mountainous interior of the Peninsula, and is in large measure a roadless wilderness containing most of the major peaks and ridges of the Olympic Mountains. Thus, the Park is an environmentally diverse entity, ranging in elevation from sea level on the coast to nearly 8000 feet on Mount Olympus (see Plate 1).
The Olympic Mountains have been described as "an unorderly array of steep-sided, jagged ridges" (Danner 1955:12). Roughly, they trend northwest to southeast, and are predominantly composed of marine sedimentary rocks which are nearly encircled by the Crescent formation, composed of marine basalts. According to widely accepted hypotheses, the marine sediments and basalts were skimmed off the oceanic crust and added to the ancient continental coast (Rau 1973). All of those sedimentary and volcanic rock formations have been subjected to such uplift and folding that "they represent some of the most complicated geology found anywhere in the world" (Danner 1955:314).
As the underlying lava dome with associated sedimentary and volcanic rocks rose (beginning about 12 million years before present) the emergent Olympics intercepted precipitation derived from the Pacific Ocean, and streams formed, radiating from the center of the mountains near the present-day Elwha River (Tabor 1975). Erosion from precipitation, Pleistocene glacial advances and recessions and Holocene alpine glaciation have resulted in the present-day river systems which drain the Olympic Peninsula. Their waters are derived from melting snowfields and alpine glaciers. Those river systems and the cardinal directions of their flows are:
Glaciation and differential erosion of bedrock and glacially-derived sediments have been the dominant agents in the creation of the present rugged topography of the interior portion of the park. On the coast, continual wave erosion, at times dramatically accelerated by severe winter storms, has caused the recession of cliffs and shoreline creating the numerous islets, sea stacks and dangerous rock reefs so characteristic of the Pacific Coast of northern Washington today.
Several large fresh-water lakes exist in or near Olympic National Park. They are: Lakes Crescent and Sutherland to the north, artificially enlarged Lake Cushman to the southeast, Lake Ozette bordering the coastal strip, and Lake Quinault to the southwest. Lakes Hills and Aldwell, to the north, are artificial impoundments created by the damming of the Elwha River. Numerous small subalpine and alpine lakes and ponds, created by glaciation of landslides, dot the interior of the Park (Danner 1995:15).
Due to the moderating influence of the Pacific Ocean, the general climate of the Park is maritime, with cool summers, mild cloudy winters, moist air and somewhat restricted daily temperature ranges for the lower elevations. Naturally, at higher elevations temperatures can be much lower and seasonal extremes are more pronounced (Wessen 1978a:5).
Often during the late summer and early fall, "fog banks and low clouds form over the ocean and move inland at night. Tops of the clouds are generally below 3000 feet; thus higher elevations are sometimes clear while the lower valleys are filled with fog." (National Park Service 1982).
As Wessen noted, "precipitation is the most dramatic and influential aspect of climate in the region" (1978a:5). Variation in the amount of yearly precipitation in the Park is marked, due to the position of the Olympic Mountains relative to the north Pacific storm track.
That variation in precipitation ranges from 80-140 inches in the western and southern lowlands, in the form of rain, to an almost incredible 200 inches per year on the highest Olympic peaks (which falls as snow). The range of variation is further extended by the well-known "rain shadow" effect, which results in a yearly rainfall of as little as 20 inches at Sequim, Washington, some 7 miles northeast of the Park.
The rain shadow effect is caused by the mountains, which act as barriers and intercept moisture-laden winds prevailing from the southwest. The damp air blows in from the Pacific Ocean, rises over the mountains, "is cooled by the higher altitudes, and its moisture condenses in the form of rain or snow." (Danner 1955:18).
Most of the yearly precipitation occurs between October and April, in the form of rather continuous light to moderate rainfall (at elevations below 1000 feet) and as snow at elevations above 2500 feet (Wessen 1978a:5). The regional snowline (elevation above which there is year around snow) is 6000 feet, which is according to Danner (1955:15) the lowest snowline in the continental U.S.
Plant Life Zones
Warren (1982) and Wessen (1978a) have written summary descriptions of the life zones which exist in Olympic National Park; this review will use the terminology employed by Warren. As both of the above-mentioned authors have noted, local conditions such as slope and exposure, as well as the extensively forested terrain, tend to obscure the boundaries of life zones. Additionally, certain plant species are found in more than one zone. Despite those conditions, the life zone concept is useful for describing the dominant plant assemblages of the Park in broad terms. In order of elevation (from lowest to highest), the life zones, with dominant trees and major understory plants, are shown in Table 1.
Table 1. Life Zones of Olympic National Park
In general terms, the distribution of life zones throughout the Park reflects an East-West division, with the Elwha River as an appropriate demarcation line. This east-west division is largely due to the topography and rain shadow effect.
In the eastern portion of the Park, temperate rain forests are virtually nonexistent because of the paucity of low elevation country. Alpine zones are also less common than in the central Olympics, which lie just to the west of the Elwha River. Montane and subalpine zones with extensive subalpine meadows predominate in the east, and the northeast portion of the Park is a further exception from the general vegetation trends, due to the rain shadow effect. There, the subalpine zone is above 4500 feet, and given the drier conditions, stands of Douglas-fir and lodgepole pine are found (Warren 1982).
West of the Elwha (exclusive of the Bailey Range and Mount Olympus) we see that subalpine zones are less in evidence, given the lower elevations, more moderate temperatures, and gentler slopes. There the Park encompasses long stretches of the drainages of the westward-flowing Calawah, Bogachiel, Hoh, Queets and Quinault Rivers. Along portions of those drainages and in the coastal strip of the Park one can observe the extremely dense vegetation of the Temperate Rain Forest, with its colonnaded, stilted trees and extensive mosses.
As Wessen noted (1978a:17), a majority (70%) of Olympic Peninsula plant species are found in the Temperate Rain Forest and lowland forest zones. In those areas there are localized plant associations which depart from the regional life zone overview (which is based upon climax species representing long-term equilibrium). For instance, plant communities with "definite temporal dimensions" are found along the rivers (Wessen 1978:20). Those temporal dimensions basically involve forest succession on stabilized river bars and terraces. Also of note are two localized plant associations found in specific environmental contexts within the Temperate Rain Forest and lowland forest zones (Wessen 1978a:21). Those environments are bogs and prairies, whose representative flora are:
Animals, because of their mobility, are not as limited in distribution as plants and many species can be found, at different times of the year, in different plant life zones.
With some exceptions, the fauna found in Olympic are very similar to those animals common elsewhere in Western Washington. As with plants, the greatest variety of land animals and birds are found in or near the Temperate Rain Forest and Lowland Forest Zones.
Table 2 summarizes the more conspicuous faunal elements found in or near the Park, exclusive of insects, amphibians and reptiles (See Table 2). Included in this list are those animals known or believed to have been useful to prehistoric and historic aboriginal inhabitants. For this reason, migratory sea mammals and deep sea fish not found in the Park per se but in waters offshore have also been included. Because of their great diversity, invertebrates such as molluscs, crustaceans and echinoderms will not be specified, although they were of great economic importance. As with the plants listed in Table 1, common names will be used, as opposed to Linnean taxonomic designations.
Table 2. Notable and Culturally Important Fauna of Olympic National Park (after Warren 1982 and Wessen 1978a)
Last Updated: 03-Nov-2009