Port of Portland
Date of Award
Master of Environmental Management (MEM)
Environmental Science and Management
1 online resource (155 pages)
Corridors (Ecology) -- Oregon -- Portland, American beaver -- Habitat, Red-legged frog -- Habitat, Western painted turtle -- Habitat, Urban wildlife management
Habitat connectivity in urban settings is critical for facilitation of safe species movement, species health, and biodiversity. Predicting the movement of wildlife through the urban environment is difficult due to the presence of barriers - natural or built features in the landscape that restrict or prohibit movement of species. Urban properties and greenspaces can serve as pathways of connectivity for wildlife movement across the complex developed matrix. Thus, land managers should assess their properties for possible connectivity functionality to promote safe wildlife movement. Land managers may not be aware of current connectivity assessment methods, therefore this project provides introductory information on connectivity assessments, including comparison of methods and results, to help land managers choose the best process for their goals and resources.
Highlighting three current connectivity assessment methods, we assess connectivity for wildlife in a north Portland greenspace and determine the relative achievements and failings for each method. The methods used include a collaborative approach to corridor mapping through land manager interviews, GIS modeling with Circuitscape and Least Cost Path analysis, and an in-field survey using the Habitat Connectivity Toolkit, a novel surveying method developed by Portland State University researchers and Metro. Connectivity is estimated for three wetland species: American beaver (Castor canadensis), northern red-legged frog (Rana aurora aurora) and western-painted turtles (Chrysemys picta). All methods were judged on landscape accuracy, barrier accuracy, ease of use and final data output to assist land managers with choosing the right method for their needs and resources.
Through a comparison of results from all methods, the Habitat Connectivity Toolkit performs best in every category except for ease of use due to the time and resources required for in-field surveying. It is recommended that managers interested in assessing corridors either use the Habitat Connectivity Toolkit for the most comprehensive corridor assessment, or use a combination of methods to best remediate the potential challenges and inaccuracies of the other methods.
Rogers, Natalie M., "Urban Connections: A Comparison of Connectivity Assessment Methods" (2017). Master of Environmental Management Project Reports. 37.