Fostering New Wildlife in Seattle's Arboretum

By Jessa Gardner & Nicole Phaysith

Exciting things are happening on Foster Island in the beautiful Washington Park Arboretum! We're seeing vibrant new landscapes and wildlife come to life following efforts to restore habitats in an area that used to be a construction zone.

Since the 520 bridge's new eastbound bridge fully opened last summer, a team of WSDOT landscape architects worked with the University of Washington Botanic Gardens and Seattle Parks to select and plant native flora and create habitats for wildlife on Foster Island. The work had been ongoing, with large sections of planting already well-established after several years of growth.

Last summer and fall marked an important moment on Foster Island as the final section of construction zone directly beneath the eastbound bridge underwent a transformation. Crews cleared the ground, while forklifts and bulldozers transported large trees and boulders. Crews established crushed rock paths to mark trails for park visitors. They also installed new irrigation and topsoil to create ideal growing conditions for the new plantings. Soon, the planting establishment period will begin – where they'll monitor the plantings for three years to ensure they thrive. Visitors can take a stroll to see native ferns, Oregon grape, evergreens, dogwood, willow, salal and more on their nature walks.

The new habitat on Foster Island isn't just fostering plants – it has also become a bustling neighborhood for a variety of creatures, big and small! Crews placed habitat logs in the landscape to provide homes for insects that birds and small mammals will feed on. The logs also provide a great home for frogs and salamanders. The logs serve a long-term purpose, providing nutrients as they decay and creating fertile new ground for more plants to grow.

Neighbors have spotted larger animals in the area as well! Anyone with binoculars or a kayak can find great blue herons, green herons, kingfishers, or even, with some luck, a bald eagle fishing in the marshy waters around Foster Island. A family of beavers built a dam near the shore under the bridge, racoon tracks can be spotted in the dirt, and a young buck found his way through the foliage to stare curiously at the humans nearby before retreating into denser trees.

This year, Punxsutawney Phil (AKA the groundhog) did not see his shadow. So, we're in for an early spring – bringing along perfect weather for hiking and animal watching. We'll see you out there on the new and improved trail!