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The three greatest threats to native biodiversity in King County (and most places) are development and associated fragmentation and loss of habitat, invasive species, and climate change. In fact, King County's biodiversity is continually changing as it is impacted by these three threats. Additionally, these three threats are often made worse by how they interact with one another. For example, as we develop new areas for homes, we build roads, and those roads provide new inlets for invading species. As the climate changes, new diseases can move in and impact our forests by killing trees. All these impacts on biodiversity are interconnected in complex ways.

Urbanization and Development

Seattle_thumbUrbanization and Biodiversity. King County is the most populous county in Washington State, and it has seen a great majority of its native landscape altered during the last 150 years. Vast areas have been converted from vast expanses of forest and wetlands to modern human land uses, particularly in the Puget Lowland Ecoregion. Activities such as industrial forestry, large areas of agriculture, and urbanization have reduced and often eliminated the connectivity of native vegetation in King County and transformed the landscape. What does all this mean for our county's biodiversity? A loss of some species, an increase of other species, and some new assemblages. Our Urbanization and Biodiversity page discusses not only the changing populations of plants and animals, but also some of the management approaches to help animals and plants co-exist with people. Additionally, our Wildlife in Urban and Urbanizing Areas page has wildlife-specific information.

Invasive Species

fragrant_waterlily_thumbInvasive Species and Biodiversity. Invasive species are typically non-native plants or animals that are highly competitive, often difficult to control or eliminate, and in extreme cases may be quite destructive of native ecosystems or economically valuable plant and animal resources. Invasive plants that are highly destructive are termed "noxious weeds," whereas destructive invasive animals are classified as "pests." Because non-native species did not evolve here with the rest of the species in the ecosystems, they often have no natural controls -- no competition. Our Invasive Species and Biodiversity page describes many of the local invading species, how they arrived, and a few things you can do to help keep more from arriving or spreading.

Climate Change

climate_change_drystreamsmallClimate Change and Biodiversity. The early effects of climate change are already being observed in King County, but they are only beginning to be understood and are presumed to increase over time. In the face of climate change, biodiversity conservation may be of critical importance for buffering the effects of rising temperatures on regional ecosystems, damping the rates of ecological change, and reducing the potential for sudden, extreme changes in the environment. Our Climate Change and Biodiversity page has information on how the climate is expected to change and how biodiversity in King County may change along with it. We also present a case study on marine shorelines and how climate change is expected to impact them.

News and announcements

Seattle Times, August 31, 2009
Mussel Invasion Closes in on Northwest Waters