Salmon could once again become common commuters in urban waterways if progress made in Pacific Northwest habitat restoration continues, says Alan Yeakley, an expert in urban ecosystems and co-editor of a new book analyzing the science behind the recovery of the iconic fish.
Yeakley, director of the School of the Environment at Portland State University, brought his expertise in the urban environment to a team of scientists working with the state of Oregon on plans for fish recovery. The book, “Wild Salmonids in the Urbanizing Pacific Northwest,” published by Springer, puts the work in a global context studying the effects of urbanization where it meets salmon habitat. In case studies from Portland, Seattle, Boise, and elsewhere in the Pacific Northwest, Yeakley and his fellow editors and authors show how stormwater management efforts, watershed-wide conservation efforts, and streamside habitat recovery have led to signs of a slowly resurging wild salmon population.
“The urban areas were written off as wastelands by fish managers,” Yeakley said. “For the longest time they have just ignored urban areas. What Portland has done is try to go against that.”
Populations of salmon and related species have been in decline for decades. Growing cities pose threats to fish habitats including polluted stormwater runoff and stream flow obstructions such as culverts and dams. In 2005, the city of Portland approved the Portland Watershed Management Plan, which included strategies for salmon and trout recovery in five major watersheds—the Columbia Slough, Fanno Creek, Johnson Creek, Tryon Creek, and the Willamette River.
Actions the city has taken under the plan have included improving stormwater management and reducing impervious surfaces by installing green roofs and bioswales, and buying up land along Johnson Creek to restore the riparian habitat along the creek bed.
Yeakley says Portland’s approach to watershed management can be adapted for use in addressing a number of climate change-related issues such as rising temperatures and changes in rainfall. “You have all these different bureaus working together on watershed issues,” he said “It’s a very integrated approach.”
The recovery of Johnson Creek is a prime example of success, with signs of a salmon population returning to the creek and scientists from other countries, such as a team from England later this year, coming to study the creek’s recovery.
Yeakley points out there is still much work to be done to restore Johnson Creek and the other waterways in the Portland area, but significant progress is being made.
“Our position is, if you don’t fix the urban areas, you won’t ever fix the larger habitat problem,” Yeakley said. “Right now there is real hope. Scientists say you have to have presence first, then abundance. We have presence. There is a glimmer of the first part of the success.”
Yeakley edited “Wild Salmonids in the Urbanizing Pacific Northwest” with Kathleen Maas-Hebner and Robert M. Hughes, both of Oregon State University’s Department of Fisheries and Wildlife. Yeakley and Hughes serve on the Independent Multidisciplinary Science Team, which was established by the Oregon Legislature in 1997 to advise the state on the scientific merit of its plan for restoring native salmon and watersheds.
“The importance of studying aquatic systems and how they react to urbanization are critical because most people in the U.S. and in the world live in urban areas,” said Hughes, senior researcher and current president of the American Fisheries Society. “Everything we do eventually ends up in the water.”
“The main audience for this book is anybody who is interested in urban systems with the potential to support salmonids,” Hughes said.
Maas-Hebner, senior faculty research assistant, said the book also looks to cover the social aspects of the science of urban fish habitats. For all the potential hazards presented by urbanization—such as pollution, erosion, and reconfiguration of streams to accommodate development—cities also have a huge asset for habitat restoration: a ready supply of volunteers. In the book she calls them citizen scientists.
“That’s a real asset that needs to get tapped,” said Maas-Hebner. “Urban areas have a workforce to help monitor these resources. There are large numbers of people who love doing that.”