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No Way Home: The Decline of the World’s Great Animal Migrations David S. Wilcove. 2007. Washington DC: Island Press. Cloth, $24.95 ISBN: 1-55963-985-7. 256 pages.

Urban structure is a mosaic of vegetation, buildings, and surfaces that create a spatially heterogeneous landscape. The authors discuss how urban designers can adopt plant ecology principles to gain new insights about system structure and function, facilitate alternatives to engineered and high-energy service solutions, and improve social conditions. The authors refer to a “design spiral,” which combines ecological theory and hydrology with the input and experience of managers and decision makers and the preferences of local residents to create new urban mosaics. For example, urban designers may develop a range of alternatives to address nitrate pollution, and then neighborhoods and communities can tailor these to meet their local preferences and needs. sparsely populated wilderness. In a densely settled metropolitan area, it can be an ethically important and politically effective value orientation, but an unrealistic and (many residents would argue) undesirable practical goal. How do we define ecological restoration in a setting where large percentages of surface area have been leveled and paved, millions of human residents skew the biodiversity index, and regional watercourses have been redirected and reengineered? Inevitably, river restoration as urban policy is both a social and technical construction (Schneider and Ingram 1997). Robert Gottlieb and Andrea Misako Azuma make this point in their chapter on the Los Angeles River, relying on William Cronon’s memorable phrase “reinvented Nature” (Cronon 1995) to acknowledge that the river and its watershed are long past returning to their pre-1800 ecological condition. An excellent snapshot of the urban river restoration dilemma is presented by Christopher Theriot and Kelly Tzoumis in their chapter on the Chicago River. Diverted to drain the city’s wastewater away from Lake Michigan and into the Mississippi River Basin, the waterway has recently enjoyed greatly improved water quality and increased aquatic biodiversity. However, the canal that accomplished this rerouting now threatens the ecological health of the entire Great Lakes region, not with wastewater but with destructive invasive species carried north and east from the Mississippi. What river conditions should be held up as the current goal of restoration? Whether restoration means accomplishing a set of ecological benchmarks or returning to a past natural state is a question that was also faced in Salt Lake City and San Jose. In each case the former definition holds sway. Ron Love tells us that the City Creek project will “restore” the watercourse from an underground culvert to the light of day through downtown Salt Lake City; it will not, however, follow its historical course, now an urban heat island of concrete and few trees. Instead, it will be diverted and reconstructed on an already-assembled linear parcel, a nearby railroad right-of-way. In San Jose, the provision and protection of fish habitat guided the restoration initiatives on the Guadalupe River. Richard Roos-Collins details the process through which resource managers, civil engineers, and hydrologists arrived at an ecological assessment of the conditions required by two native fish species to thrive; the task of the “restoration” project was then to design, create, and continually monitor those conditions. In Washington DC, Uwe Steven Brandes all but suggests that ecological restoration of the Anacostia River is a pipe dream. Located at the mouth of a heavily urbanized watershed, 83% of which is in the state of Maryland, the likelihood of a $2 billion restoration initiative without enforceable jurisdictional authority is unlikely (p. 54). Such seemingly insurmountable difficulties are echoed in Melissa Samet’s sobering assessment of the U.S. Army Corps of Engineers, whose recent reinvention as environmental Book Reviews