Introduction to wild salmonids in the urbanizing Pacific Northwest

Abstract

The central question we address in this book is: Can viable wild salmonid populations coexist with humans in urban and urbanizing areas? Our focus is on wild salmonids in North America's Pacific Northwest, but the relevance of this book extends to salmonid-bearing watersheds threatened by concentrated human settlement anywhere on the planet. Despite countless management initiatives to recover these vital species and their habitats, wild salmonids have continued to decline inexorably over the past century and a half in the Pacific Northwest. While it has long been understood that intensive land use severely degrades salmon bearing streams, urban areas have received much less focus in salmonid management and rehabilitation efforts. Far more attention has been placed on salmonid impacts from factors such as timber harvest, agriculture, dams, mine operations, and river channel modification. Yet many salmonids must traverse substantial urban areas at least twice in their lifetimes, once as out-migrant juveniles and again as adults returning to spawn. Moreover, many urban areas exist along important river confluences and slough areas that were historically critical refuges for salmonids at various times in their lifecycles. Finally, human populations and economies continue to both increase overall and further concentrate in urbanizing areas. Cities and rural-residential development constitute an ever increasing part of the impact on wild salmonids. Not only is it imperative that we increase our understanding of the growing threat that urban areas exert on wild salmonid populations, but we also desperately need to increase our capability to facilitate the survival and recovery of wild salmonid populations in the face of urban growth and development.