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The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ecological obstacles to project success. The nutria (Myocastor coypus) is an invasive, semi-aquatic rodent native to South America that causes detrimental ecological impacts in riparian and wetland habitats throughout its introduced range, and techniques are needed to reduce nutria herbivory damage to urban stream restoration projects. We assessed the efficacy of standard Vexar® plastic mesh tubes in reducing nutria herbivory damage to newly established woody plants. The study was conducted in winter-spring 2009 at Delta Ponds, a 60-ha urban waterway in Eugene, Oregon. Woody plants protected by Vexar® tubes demonstrated 100% survival over the 3-month initial establishment period, while only 17% of unprotected plantings survived. Nutria demonstrated a preference for black cottonwood (Populus balsamifera ssp trichocarpa) over red osier dogwood (Cornus sericea) and willow (Salix spp). Camera surveillance showed that nutria were more active in unprotected rather than protected treatments. Our results suggest that Vexar® plastic mesh tubing can be an effective short-term herbivory mitigation tool when habitat use by nutria is low. Additionally, planting functionally equivalent woody plant species that are less preferred by nutria, and other herbivores, may be another method for reducing herbivory and improving revegetation success. This study highlights the need to address potential wildlife damage conflicts in the planning process for stream restoration in urban landscapes.

Pools provided by beaver (Castor canadensis) contribute to critical habitat requirements of salmonids in fluvial systems of the Pacific Northwest, therefore more land managers are interested in managing watersheds that include beavers or engaging in beaver-related restoration projects. We evaluated the utility of applying an existing beaver habitat suitability model to better understand beaver dam site characteristics in coastal Oregon, identify optimum dam site locations, and guide future beaver-related restoration efforts. We used a combination of t-tests, Wilcoxon rank sum tests, and a stepwise discriminant function analysis to examine stream habitat associations with field data collected at known and predicted dam sites at reach and pool/riffle levels. We found bank-full width, valley floor width, and channel gradient performed well in predicting dam locations across the Alsea River Basin. Known dam sites had wider valley floors, shallower shoreline slopes, and fewer larger, deeper pools than predicted sites. Overall, our results suggest the beaver habitat suitability model combined with a digital elevation model can be used to guide where beaver dams may occur within the Alsea River Basin, yet they do not capture fine scale habitat associations that may lead to a settling response in beavers. For example, presence of large deep pools may be necessary for beavers to escape predation before and during dam building. Results from our study may be used to prioritize potential dam sites in other coastal basins that have similar geomorphic characteristics.