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Union Bay Natural AreaImages of tours and restoration work inside the Union Bay Natural Area

Work Parties!

Get involved, have fun, meet people and GET DIRTY! For info on upcoming volunteer work parties, have a look at the UWBG’s volunteer calendar.

planting trees with blue tubes



2014 Slideshow by Professor Kern Ewing

Banking On New Wetlands When Old Ones Vanish, article and KUOW radio show from July 22, 2011 featuring UWBG professor, Kern Ewing.

Union Bay, the movie! Starring Blue Heron, Cooper's Hawk, Mallard Duck and a cast of thousands. Produced by Mark O'Connell

At the Fill: Photographs from the Union Bay Natural Area, is an online book filled with beautiful images by Doug Plummer.

In My Nature, a book by Constance Sidles exploring the Natural Area.

Buy a beautiful photo book and support UBNA
Seasons book cover image

ubna mapThe Union Bay Natural Area is a public wildlife area, natural restoration laboratory, and an important habitat next to Lake Washington. At 74 acres, with 4 miles of shoreline, it is the second largest natural system left on the lake. Considered one of the best bird-watching sites in the city of Seattle, over 200 species of birds have been sighted here. Some long-time residents call this area the Montlake Fill.

The Union Bay Natural Area is managed by UW Botanic Gardens to maintain and enhance plants, wildlife and landscape values while serving as an outdoor laboratory for research, teaching and public service. Questions about UBNA should be directed to uwbg@u.washington.edu or 206-543-8616.

WSDOT Mitigation Project for Union Bay Natural Area

Read about events & updates: UBNA Blog

Take a Virtual Walk in UBNA!

View Larger Map

Yesler Swamp Trail (East Basin)

The area east of the Center for Urban Horticulture parking lot, is part of the Union Bay Natural Area. Learn about the history of the area and join in work parties hosted by the Friends of Yesler Swamp.

UBNA Research Articles

Long-Term Effects of Initial Site Treatment on Fescue in a Novel Prairie Ecosystem (Washington)

Nate Hough-Snee, Jonathan D. Bakker and Kern Ewing

In prairie restoration, site preparation is a key step in altering environmental conditions to favor the establishment of desirable plants over invasive species. In 2008, we revisited prairie plots restored in 1994 to examine the long-term impacts of initial site treatments on the survival and expansion of planted fescues (Festuca spp.). To enhance fescue plantings and reduce invasive weeds over the long term, we recommend the use of fire and plant removal as site preparation treatments. We also encourage research into soil impoverishment as a means of lowering nutrient availability and giving fescue a competitive advantage.

Ecological Restoration. March 1, 2011 vol. 29 no. 1-2 14-17

Parking lot to Wet Prarie

UWBG student Nate Hough-Snee presented a poster on the UBNA's restored E-5 parking lot at the Society of Wetland Scientists annual meeting in Salt Lake City, UT entitled, Parking lot to wet prairie: a vegetation assessment of ecological restoration at the Union Bay Natural Area, Seattle, WA. Co-authors include SFR alumni Lexine Long and Lacey Jeroue and UWBG faculty Kern Ewing.

Parking lot to Wet Prarie Abstract

In 2008, we examined the vegetation of a former parking lot that, ten years ago, was restored to wet prairie with mounding and vegetation installation in the Union Bay Natural Area (Seattle, WA). In wetland restoration mounding is a technique commonly used to create microhabitats of differing resource availability on top of and adjacent to mounds. This microtopography creates environmental filters for vegetation based on plant adaptations to flooding stress and tolerance to drying. Thirty sample mounds were randomly selected and divided into two half-meter plots on top of each mound and one half-meter plot in each of the northerly and southerly inter-mound spaces, for a total of 120 plots. Each plot was surveyed for elevation and measured for soil water content, while we described vegetation by percent cover. Because sampling was not independent, we used permutation procedures for analyses, finding that vegetation differs significantly between mound and inter-mound spaces while soil moisture is driven by mound elevation and position. Mounds located in wetland zones had more non-native plants on top of the mounds than the adjacent saturated inter-mounds that were largely comprised of native hydrophytes. Restoration efforts were complicated by competition from invasive plants that played a role in community development regardless of mound zone. We conclude that the resulting novel wet-prairie vegetation community may be driven by microtopographic variation and that the corresponding environmental filters allow native vegetation to persist and establish across this novel ecosystem while hypothesizing that invasive species persist due to competitive advantages.

Learning from a Landfill

Congratulations to UW graduate students Justin Howell and Nate Hough-Snee for their article, "Learning from a Landfill," which appears in SERNews (23:2), the newsletter for the Society of Ecological Restoration International. Read the full article here!

Union Bay Natural Area and Shoreline Management Guidelines & Maps

UW Botanic Gardens has updated the Union Bay Natural Area and Shoreline Management Guidelines. This update to the 1996 management plan includes a number of guidelines and specific recommended management actions to achieve the long-term goals for the area. The new draft also assesses the conditions of different sub-areas, including sections of the Loop Trail and the Unmanaged Wildlife Area along Lake Washington. Recommendations include adding native plants, maximizing habitat diversity, and increasing and coordinating teaching and research in the Union Bay Natural Area.

Full text of Guidelines (2.53MB)


Last modified:
Wednesday, 13-Apr-2016 16:35:12 PDT