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Planning riparian restoration to resemble historic reference conditions requires an understanding of both local and regional patterns of plant species diversity. Thus, understanding species distributions at multiple spatial scales is essential to improve restoration planting success, to enhance long-term ecosystem functioning, and to match restoration planting designs with historic biogeographic distributions. To inform restoration planning, we examined the biogeographic patterns of riparian plant diversity at local and regional scales within a major western U.S.A. drainage, California's Sacramento-San Joaquin Valley. We analyzed patterns of species richness and complementarity (β-diversity) across two scales: the watershed scale and the floodplain scale. At the watershed scale, spatial patterns of native riparian richness were driven by herbaceous species, whereas woody species were largely cosmopolitan across the nearly 38,000 km 2 study area. At the floodplain scale, riparian floras reflected species richness and dissimilarity patterns related to hydrological and disturbance-driven successional sequences. These findings reinforce the importance of concurrently evaluating both local and regional processes that promote species diversity and distribution of native riparian flora. Furthermore, as restoration activities become more prevalent across the landscape, strategies for restoration outcomes should emulate the patterns of species diversity and biogeographic distributions found at regional scales. © 2011 Society for Ecological Restoration International.

Adult salmon that stray when they escape into non-natal streams to spawn is a natural phenomenon that promotes population growth and genetic diversity, but excessive stray rates impede adult abundance restoration efforts. Adult San Joaquin River (SJR) Basin fall-run Chinook salmon (Oncorhynchus tshawytscha) that return to freshwater to spawn migrate through the San Francisco Bay and Sacramento–San Joaquin River Delta (Delta). The Delta has been heavily affected by land development and water diversion. During the fall time-period for the years 1979 to 2007 Delta pumping facilities diverted on average 340% of the total inflow volume that entered the Delta from the SJR. The hypothesis tested in this paper is that river flow and Delta exports are not significantly correlated with SJR salmon stray rates. Adult coded-wire-tagged salmon recoveries from Central Valley rivers were used to estimate the percentage of SJR Basin salmon that strayed to the Sacramento River Basin. SJR salmon stray rates were negatively correlated (P = 0.05) with the average magnitude of pulse flows (e.g., 10 d) in mid- to late-October and positively correlated (P = 0.10) with mean Delta export rates. It was not possible to differentiate between the effects of pulse flows in October and mean flows in October and November on stray rates because of the co-linearity between these two variables. Whether SJR-reduced pulse flow or elevated exports causes increased stray rates is unclear. Statistically speaking the results indicate that flow is the primary factor. However empirical data indicates that little if any pulse flow leaves the Delta when south Delta exports are elevated, so exports in combination with pulse flows may explain the elevated stray rates. For management purposes, we developed two statistical models that predict SJR salmon stray rate: (1) flow and export as co-independent variables; and (2) south Delta Export (E) and SJR inflow (I) in the form of an E:I ratio.

Roads have a variety of adverse impacts on wildlife populations and can seriously impact rare species. Numerous roads are present throughout the range of the endangered San Joaquin kit fox (Vulpes macrotis mutica), and many more are planned. We review existing literature and data to assess potential impacts from roads on kit fox conservation and recovery. In addition, we discuss mitigation strategies with their potential benefits.