The hills are alive THE METHOW VALLEY TEEMS WITH FLORA AND FAUNA

BY SANDRA STRIEBY

In its 80-mile run from headwaters to the Columbia River, the Methow River traverses a richly varied watershed shaped by volcanoes, glaciers, and floods and populated by a diverse array of plants and animals.

Increasingly, the valley’s landscape is being re-worked by fire and climate change, which affect the types, abundance, and distribution of local flora and fauna. W hat follows is an overview of the valley’s habitat types, and a look at some of the plant groups and animal species that occupy them.

The Methow Valley offers four major habitat types for plants and animals to colonize: forest, shrubsteppe, riparian and aquatic.

• Forested lands receive enough moisture to support trees, and vary from dry forests where trees may be widely spaced to denser stands in cooler and wetter areas — often at higher elevations.

• In the shrub-steppe, trees are few or non-existent due to lack of water; shrubs fill the ecological niche that’s occupied by trees in forests. Long considered barren wastelands, areas of shrub-steppe are now understood to be important storehouses of plant and animal diversity.

• Riparian areas — lands adjacent to water bodies — have access to plenty of water and support dense stands of trees and shrubs. Straddling the edge between water and land, they house abundant resources and are more important than their size would suggest.

• Aquatic systems — rivers, streams and lakes — are home to more life than meets the eye. The valley’s rivers and lakes teem with life, including birds, mollusks, turtles, frogs, insects, microorganisms and more. When it’s safe, swimming, snorkeling or wading can be great ways to discover the activity below the surface.

■ K EYSTONE SPECIES

All of the Methow’s habitat types support keystone species — plants and animals that provide broad support for the ecosystems to which they belong.

The concept of keystone species was introduced about 50 years ago. It’s supported by our growing understanding that complex ecological relationships are often held in place by a single species or group of species.

Just as a single keystone is able to support an architectural arch, and all the weight above it, so can a keystone species play an outsized role in a natural system. The sections on flora and fauna that follow will introduce a few of those species.

■ T HE FLORA

Forests, shrub-steppe, and riparian areas all support a mix of vegetation types, including trees, shrubs, and forbs (the botanical term for grasses, wildflowers, and other non-woody flowering plants). Trees grow primarily in forested and riparian areas. Generally, shrub-steppe is too dry to support them, although they may appear in spots where there’s adequate moisture.

Ponderosa pine and Douglas fir are two prominent tree species at lower and middle elevations. Both are adapted to fire, and forests like those in the Methow Valley thrive on low-intensity burning every few years.

Other pines and true firs become more common at higher altitudes, and there’s a smattering of Western red cedars in wet places. Larches drape mountain slopes with color when their needles turn gold in the fall. Wildfires have swept the valley as often as not in the last decade, dramatically changing forests and affecting all aspects of forest ecology, including use by plant and animal species.

Riparian zones, and wetter spots within forests, may support cottonwoods, aspens, alders, willows and birches. Willows are keystone species; across the U.S., they support hundreds of kinds of insects

— some of those are pollinators; others provide food for baby birds. Shrubs provide enormous value to arid-zone ecosystems, offering pollen, nectar, berries, seeds, and leafy browse that feed numerous animal species. With their colorful flowers and fruit, shrubs are a delight to the eye as well. Chokecherries and other members of the genus Prunus are keystone species, critical to the survival and reproduction of the animal kingdom.

In the shrub-steppe, where few trees survive, shrubs such as sagebrush, bitterbrush and rabbitbrush take their place, providing perches, refuge and nesting places for birds and small mammals. Sagebrush is considered a keystone species because it’s such an important element of the ecosystem, providing direct support to hundreds of species and enriching the thin mineral soils in which it grows with nutrients and organic matter. Like the valley’s forests, much of the shrub-steppe has been altered by recent fires.

Although they got off to a slow start this year thanks to heavy snow and a cool spring, wildflowers will bring color to the valley throughout the summer. Bloom starts soon after the snow melts at lower elevations, and moves upward as snow recedes and the soil warms. Flowering will peak in the high country in July, and last into fall where temperatures and soil moisture permit.

Ranging from tiny flowers like Whitlow-grass to big eye-catching species like balsamroot, wildflowers are essential elements of the valley’s ecosystem, providing food and habitat for dozens of animals. Many forbs also benefit from hummingbirds, bees, butterflies, and other pollinators, which help them reproduce.

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T He Fauna

Hundreds of species of animals spend at least part of their life cycles in the valley’s forest, shrubsteppe, riparian and aquatic habitats. They include more than 270 k inds of birds, 70 other vertebrate species, and more invertebrates than we’ve been able to catalog. Here’s a brief introduction to some of the animals that contribute to the Methow’s web of life:

• Beavers. Beavers shaped much of the landscape of North America. In recent years they’ve gained increased recognition for their role in creating habitat for plants and other animals and retaining water in the landscape.

Birds, insects, fish, mammals, frogs, salamanders and more thrive in areas influenced by beavers. Some of the water trapped by beaver dams seeps into the ground to support moisture-loving plants; some provides habitat for fish, amphibians, reptiles and water-dependent mammals like muskrats and mink; some slowly makes its way through the dam and flows downstream, recharging rivers during the hot dry summer months.

The plants that surround beaver ponds attract insects and birds; the insects feed the birds and also the fish. The beavers’ role in watershed function has earned them the moniker “ecosystem engineers” along with recognition as a keystone species.

• Bats. The Methow is home to more than a dozen species of bats, the only mammals able to fly under their own power. Ranging from tiny Western Pipistrelles, the smallest bats in the U.S., to Big Brown bats with wingspans of at least a foot, the valley’s bats are excellent hunters and prodigious consumers.

Each one catches thousands of insects every night, using echolocation to find its prey. Bats contribute to plant health and human comfort by reducing populations of mosquitoes, wasps, beetles, grasshoppers and other insects. They share the ability to echolocate — use sound to navigate — w ith a few other kinds of animals, including many marine mammals. Echolocation has contributed to a number of human technologies, including airport security and remote sensing.

• Salmon. As streams and rivers flow toward the sea, they carry a load of nutrients with them — dissolved and suspended minerals, plant and animal detritus all leave the watershed by water power. Salmon journey to the oceans to feed, then return, bringing loads of nutrients to replenish their home streams.

Those nutrients support other animals — 75 of the Methow Valley’s bird, mammal, amphibian and reptile species feed on salmon, their eggs, and their carcasses, and some of them carry nutrients away from streams to t he uplands, where they improve soil fertility.

■ R ESOURCES

Washington Department of Fish and Wildlife

• Black Bear: https://wdfw. wa.gov/species-habitats/species/ ursus-americanus.

• Cougar: https://wdfw. wa.gov/species-habitats/species/ puma-concolor.

• Western rattlesnake: https://wdfw.wa.gov/ species-habitats/living/ snakes#preventing-conflicts.

• To search for other species: https://wdfw.wa.gov/ species-habitats/species.

North Central Washington Audubon Society: https://ncwaudubon. org.

Washington Native Plant Society: https://www.wnps.org.

T he Methow Naturalist: https:// www.methownaturalist.com.