Information about the Interactive Habitat Map
- Where does the data for the Interactive Habitat Map come from?
- What did the 1999-2000 survey of Seattle urban forests uncover?
- Why is this data important?
- Next steps - The Citywide Habitat Assessment (CHA)
Where does the data for the Interactive Habitat Map come from?
Seattle Urban Nature Project (SUNP) was founded in 1998 to survey and map the vegetation and wildlife habitat in Seattle. In 1999 and 2000, SUNP conducted a citywide vegetation inventory on 8,000 acres of public lands and open space in Seattle. This effort, known as the Seattle Public Lands Habitat Survey, was the first of its type and unique in that it spanned administrative boundaries. The purpose of this effort was to provide city managers and citizens with information about the city's natural resources.
Open space was delineated into one of 33 habitat types described in the Seattle Department of Parks and Recreation's publication "Urban Wildlife and Habitat Management Plan" (Miller 1994). A dichotomous key was used to classify habitat types. The full key is available on our website from this link. Each individual section of habitat, called a polygon, was mapped to create a Geographic Information System (GIS) layer depicting the location of these habitats throughout the city. A list of plants present in each polygon was recorded, with percent coverage estimated for each species.
As a result of this two year effort to collect data, SUN produced an atlas featuring habitat maps for over fifty areas in Seattle and a data disc for public use. The maps from this atlas are available for download on our website in PDF format. The data collected in the survey is a management resource utilized by city agencies, community groups, and local non-profit organizations involved in restoration, acquisition, and conservation of natural areas within the city. The survey also provides baseline information for monitoring habitat conditions in the future.
For a more detailed analysis of this survey, see "A Citywide Survey of Habitats on Public Land in Seattle, a tool for urban restoration planning and ecological monitoring." Click here to see the full article.
What did the 1999-2000 survey of Seattle urban forests uncover?
Based on SUN's 1999-2000 survey, it was discovered that 2700 of the 8000 acres of public land found in Seattle are forested. Forest types and their percentage throughout the city include:
- Deciduous (70%)
- Conifer (12%)
- Conifer Deciduous Mixed (13%)
- Broadleaf Evergreen (Madrone) (1%)
- Deciduous Broadleaf Evergreen Mixed (2%)
- Conifer Broadleaf Evergreen Mixed (1%)
- Riparian (1%)
One of the goals of the 1999-2000 survey was to measure the types and amounts of invasive species present in Seattle's urban forests. The five most invasive species in Seattle's forests are:
1. Himalayan blackberry (Rubus discolor) - 1020 acres
2. English Ivy (Hedera helix) - 718 acres
3. Scotch Broom (Cytisus scoparius) - 118 acres
4. English Holly (Ilex aquifolium) - 75 acres
5. Western Clematis (Clematis vitalba) - 73 acres
The 1999-2000 survey showed that approximately 20 non-native species are invasive in Seattle's forests. When the percent cover of all of these species are combined together, the following information emerges about the condition and health of our forests:
Table 1. Percent cover of invasive species in Seattle's urban forests |
|
Percent Cover of invasive species |
Percent of total forested acres in Seattle |
Trace (0-10%) |
11% |
Low (11-30%) |
25% |
Medium (31-50%) |
17% |
Moderately High (51-80%) |
18% |
High (81-100%) |
9% |
Very High (>100%) |
20% |
The survey also showed which parks in Seattle are in the best condition and have the greatest native plant diversity. Based on the 1999-2000 survey of Seattle’s public lands, the 20 most species rich parks or natural areas are:
University of Washington
Carkeek Park
Discovery Park
Thorton Creek Greenspace
Ravenna Park
Schmitz Park
West Duwamish Greenbelt
Burke-Gilman Trail
Jackson Park Golf course
Lincoln Park
Kubota Gardens Park
Fauntleroy Park
Camp Long
Washington Park Arboretum
Westcrest Park
Duwamish Head Greenbelt
Golden Gardens Park
East Duwamish Greenbelt
Puget Creek Natural Area
Seward Park
The 1999-2000 survey data have been the foundation for management decisions in the City of Seattle for the past five years, and is the basis for the Green Seattle Partnership.
This information can help forest stewards prioritize restoration activities in their local parks and open spaces. For example, the forested areas throughout Seattle that are highly invaded are good candidates for intensive restoration activities. On the other hand, the forested areas in Seattle that have very low cover of invasive species should be protected from invasive species encroachment. Therefore, a forest steward could target restoration activities in surrounding areas to create a buffer and extend these intact areas.
Another important value of this data is the ability to educate the public about the health of urban forests and encourage stewardship of local parks. Displaying the data in an interactive habitat map is a powerful tool that allows people to explore their public forests.
Next steps - The Citywide Habitat Assessment (CHA)
In 2005, SUN launched a habitat monitoring program known as the Citywide Habitat Assessment (CHA). This assessment builds on the data collected during the 1999-2000 survey. The purpose of this project is to assess the state of Seattle’s forests over time, using a repeatable, accurate methodology that measures specific indicators of forest function and health. This information will provide city managers and community groups with the information they need to most effectively manage Seattle’s urban forests. The ability to assess the health of these forests over the long-term will help managers to:
- Reduce the decline or loss of habitats and species
- Determine whether the desired condition of Seattle’s habitats has been achieved
- Identify successes and limitations of management strategies and allow for changes to these strategies
- Make the best use of limited resources by identifying which habitats need the most attention
To learn more about this project and read publications that have resulted from this research, please visit our Citywide Habitat Assessment page.
