Urban Wildlife and Landscape Connectivity
Understanding our wild neighbors in Seattle—and what we can do to help them.
Here's a question for you, Seattle: How well do you know your neighbors?
Urban wildlife, or wildlife that lives—and in some cases, thrives—in urban environments, are some of the most neglected populations when it comes to discussions of habitat conservation.
While we might think of sprawling, untouched wildlands when we think of habitat conservation, for many animals home looks a lot less like this...
... and a lot more like this.
As more people move away from rural areas and move into dense and rapidly expanding urban areas, it becomes even more crucial to include urban wildlife in our discussions of habitat conservation.
This is especially true for Seattle, where our location places us in between 86 miles of Puget Sound shoreline and the second largest lake in Washington, with the Cougar-Squak-Tiger Mountain Corridor providing miles of connected wild habitat to our East.
So, that begs the question: is wildlife here in Seattle?
Photos sourced from The Seattle Urban Carnivore project's Urban Carnivore Spotter
Yes, absolutely!
Research done in collaboration with Seattle University and the Woodland Park Zoo has drawn attention to some of the diverse species that call the greater Seattle region's urban and suburban areas home.
Through their web-based Carnivore Spotter, Seattle residents can submit observations—including photos and videos—of carnivore activity in their neighborhood. These observations are then reviewed by project staff and uploaded to their interactive online map .
To learn more about the The Seattle Urban Carnivore project, click here .
Some common species reported included coyotes (50% of all reports within the first year), raccoons (20%), bobcats (11%), black bears (9%), river otters (5%), opossums (3%), and cougars (2%). 1
As sightings move eastward into more undeveloped land, the types of species change. While raccoons and coyotes are abundant in dense urban areas, bobcats prefer partially wooded suburban or rural areas, and black bears were mainly sighted in less developed areas near large greenbelts.
However, living in urban areas brings unique challenges to wildlife.
Otter crossing!
Humans are noisy, cars are dangerous, pets are aggressive... The list goes on. Although many of these species have adapted miraculously to their urban environments, rapid urbanization still presents many challenges to wildlife populations that are being forced to adapt to our growing presence.
Addressing each of these challenges is a collaborative effort between local city planners, conservation biologists, state governments, and city residents (that's you!) to build an environment where cohabitation is possible.
That being said, there is one danger to urban wildlife that stands out among the rest...
This map shows wildlife collision data along state and local roads in Washington from 2015-2021.
Each point represents an animal that was removed off the road following a fatal collision.
Data sourced from WSDOT's wildlife carcass removal database (2015-2019) and WDFW and WSDOT's King County Local Roads Salvage database (2016-2021).
Roads pose a variety of challenges to urban wildlife. Beyond the risk of a fatal collision, large roadways can cut off wildlife from resources and isolate populations. This can result in low genetic diversity in urban wildlife populations, which in turn results in higher risk of disease and greater difficulty adapting to their changing environments. 2
Landscape connectivity describes how features of a landscape, such as roads, might "facilitate or impede movement of organisms among resource patches" (Smith et al., 2019).
Landscape connectivity is crucial to consider for urban areas, where wildlife populations must navigate across perilous terrain to access necessary resources, including other breeding populations.
So how can we increase landscape connectivity for urban wildlife in the Seattle area?
New WSDOT video shows benefits of wildlife crossings, with more coming to Washington.
The Washington Department of Transportation (WSDOT) has overseen multiple projects focusing on habitat connectivity. One such project was the Snoqualmie Pass east wildlife overpass across I-90, which has seen significant traffic from all manner of wildlife.
WSDOT is hoping to expand these efforts with both wildlife overpass and underpass projects that would allow for safer passage along natural migration routes and in areas with high wildlife collision rates.
Source: WSDOT
One opportunity to increase landscape connectivity comes in the form of WSDOT's fish barrier removal projects.
These are areas where WSDOT is planning to correct barriers for salmon passageway, and where there might be opportunity to expand these passageways to accommodate larger wildlife passage as well.
When expanded, these combined fish and wildlife passages can allow for the movement of a variety of species, helping link populations and mitigate wildlife mortality on roadways.
This map shows areas where WSDOT plans to expand salmon passageway by 2023, and where there might be an opportunity for a combined fish and wildlife crossing.
Data sourced from WSDOT .
However, expanding these fish passageways is an expensive and time-consuming endeavor—therefore, WSDOT must be strategic about where they choose to include wildlife crossings.
This is where GIS comes in...
By utilizing the combined data from the Carnivore Spotter program and the roadway collision databases, we can begin to see patterns in urban wildlife activity.
By analyzing these patterns, we can begin to understand population "hotspots" and how urban wildlife populations are navigating their environment.
Left: Carnivore Spotter (Seattle Urban Carnivore Project) | Right: Roadway Collisions (WSDOT & WDFW)
From there, we can more effectively decide where to place wildlife crossings in conjunction with fish barrier removal sites.
As our city rapidly expands, it's important that we all think about how we can be better neighbors to the urban wildlife populations that call Seattle home.
Whether that be growing a native plant garden, keeping your cat indoors, or driving a little more carefully on our roads, it's necessary that we all do our part to support the incredible biodiversity that exists in our unique corner of Washington.
“From the perspective of someone who lives in a city or suburb, conservation is too often something that happens somewhere else—in a national park, wilderness area, or rainforest—and is experienced second-hand (if at all) on television or in a magazine… It is important to communicate that many of the same ecological processes taking place in television nature shows also occur, with perhaps less charismatic players, in one’s own backyard" (Miller and Hobbs, 2002).
Copyright © 2023 Carissa G. Caulton
A special thanks to Glen Kalisz, Habitat Connectivity Biologist at WSDOT, and Mark Jordan, Associate Biology Professor at Seattle University. This project would not have been possible without their support!
References:
Mcdonald, R. I., Kareiva, P., & Forman, R. T. T. (2008). The implications of current and future urbanization for Global Protected Areas and Biodiversity Conservation. Biological Conservation, 141(6), 1695–1703. https://doi.org/10.1016/j.biocon.2008.04.025
Miller, J. R., & Hobbs, R. J. (2002). Conservation where people live and work. Conservation Biology, 16(2), 330–337. https://doi.org/10.1046/j.1523-1739.2002.00420.x
1 Remine, K. (2020, November 24). Carnivore spotter: Highlights from the first year! Woodland Park Zoo Blog. Retrieved March 5, 2023, from https://blog.zoo.org/2020/11/carnivore-spotter-highlights-from-first.html
2 Smith, J. G., Jennings, M. K., Boydston, E. E., Crooks, K. R., Ernest, H. B., Riley, S. P., Serieys, L. E., Sleater-Squires, S., & Lewison, R. L. (2020). Carnivore population structure across an urbanization gradient: A regional genetic analysis of Bobcats in Southern California. Landscape Ecology, 35(3), 659–674. https://doi.org/10.1007/s10980-020-00971-4
Woodland Park Zoo. (2023). Woodland Park Zoo. Seattle Urban Carnivore Project . Retrieved March 5, 2023, from https://www.zoo.org/seattlecarnivores
WSDOT. (2022, February 24). Reducing the risk of wildlife collisions. WSDOT. Retrieved March 5, 2023, from https://wsdot.wa.gov/construction-planning/protecting-environment/reducing-risk-wildlife-collisions
