Management of urban aquatic habitats for native wildlife, such as amphibians, is an important contemporary goal for many municipalities. However, our understanding of how local and landscape characteristics of urban aquatic habitat promote or inhibit amphibian occupancy and recruitment is limited. In this study, we examined amphibian community composition and occurrence patterns in ponds, wetlands, and swales of Gresham, Oregon. We collected occurrence data for five native amphibians: northwestern salamander (Ambystoma gracile), long-toed salamander (A. macrodactylum), Pacific chorus frog (Pseudacris regilla), northern red-legged frog (Rana aurora aurora), and rough-skinned newt (Taricha granulosa) as well as one non-native amphibian, the American bullfrog (Lithobates catesbeianus). One hundred sites were surveyed from 2007 to 2013. Local and landscape attributes were characterized for each site, and potential drivers of species occupancy were evaluated using a combination of multivariate approaches and generalized linear models. In general, percent impervious surface and distance to nearest forest patch, both associated with urbanization, were negatively correlated with site occupancy for all species. Non-native vegetation was also negatively associated with occupancy of three species (long-toed salamanders, Pacific chorus frogs, and northern red-legged frogs). In contrast, occupancy was positively correlated with pond depth and hydroperiod length for all species. We found evidence of two distinct groups of co-occurring amphibian species driven by habitat depth Urban Ecosyst and hydroperiod. Finally, we report results of threshold analyses that examined speciesspecific habitat associations. This study describes urban habitat associations of a native amphibian community, identifies factors with positive, negative or mixed relationships with amphibian species, and is an important step in informing the management of urban aquatic habitat to promote persistence of native amphibians.

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The Management Plan is comprised of three parts: Chapter 2: Habitat assessment of the headwaters property Chapter 3: Assessment of the turtle population Chapter 4: Management Plan and recommendations based on population evaluation and habitat assessment Chapter 2: Habitat Chapter 4: Management Plan The management plan combines the results of the habitat section (Chapter 2) and the population assessment (Chapter 3) to develop actionable recommendations for conserving this turtle population and its habitat. General recommendations are first made for the entire site, providing recommendations for maintaining the site into the future. I then propose two different restoration plans are proposed as recommendations for restoring the newly acquired Gantenbein Dairy property specifically with turtle habitat enhancements as a priority (Chapter 4: Plan 1 and 2). History of the Willamette Valley: Urbanization in the Valley The Willamette Valley in Oregon, comprising of 9,100 km 2 , was settled by Europeans in the 1800s (Taft and Haig 2003; Benner and Sedell 1997, Hulse et al. 1998). The Willamette Valley is bordered by the Columbia River to the north, and expands to just south of Eugene (Figure 1.1). The valley is bordered by the Cascade Range to the east and the Coast Range to the West. It has a cool Mediterranean climate with an average rainfall of 100-125 cm (Jackson and Kimberling 1993). Since settlement, the Valley has been dominated by farming, industry, and urbanization (Hulse et al. 1998; Oetter et al. 2000). Titus et al. (1996) found that 456,119 hectares of wetland and riparian area in the Willamette Valley have been lost since European settlement (1840). Most of the wetland loss has been due to agriculture (70%) and urbanization (6%) (Bernert et al. 1999). Many species of wildlife depend on these disappearing habitats. As urbanization of the Willamette Valley continues to increase, a focus on urban wildlife, including turtles, should be emphasized. In fact, many of the populations of turtles found in the Willamette Valley are found in high-density urban areas (Gervais et al. 2009). Gresham, located just east of Portland, Oregon, in the northern end of the Willamette Valley (Figure 1.1) is in the largest urban area (Portland Metro Area) of the Valley and in Oregon. Gresham is the fourth largest city in Oregon with a population of 109,000 (2012 census). The 60.9 km 2 city features many parks, natural areas and creeks, but it is still highly urbanized, with 41 percent of the city being impervious or "built" surface (Figure 1.2).