Project Statement  

Using birds as a biodiversity indicator, this project develops a methodology for integrating viable ecosystems and habitats into marginalized urban spaces to augment quality and connectivity across scales. Road rights of way in Surrey, Canada are used as case studies to explore the integration of avian habitat, ecological function, and human programming as connective conduits. This project demonstrates the role of landscape architects in finer grained design within landscape ecology structural patterns.

Project Narrative

The Research Problem
With an annual global population growth of over 92 million people there is a decrease in per capita ecosystem services, even without a net loss in ecosystems. This highlights the importance of maximizing the ecological potential of all spaces. Despite the detrimental effects associated with urbanization, if properly designed and managed urban areas situated in critical ecological locations can play an important role in supporting biodiversity at local, regional and even wider scales. 

Creating and maintaining connectivity between fragmented elements of natural systems is vital to regional biodiversity as it facilitates the migration of species and genetic material and enhances ecological functions and services which support all life. Ecological corridors have been recommended as a means for providing functional connectivity between fragmented patches in conservation theory since the 1970s. There has been significant theoretical work in the area of landscape ecology, a discipline focusing on the "structural pattern of a landscape or region" (Dramstad & Forman, 1996). This project involves landscape ecology principles but focuses on a finer grained detail of the diversity and quality of habitat types and plant associations within these spatial patterns.

In developed areas it can be difficult to acquire land of adequate quality and quantity to create functional and connective corridors. This project focuses on a smaller scale of networks and connectivity, on land that is already publicly owned and often ignored for all but it's primary focus of automobile transportation:  the road right of way. While the network itself may not change in size or location, the design of road rights of way holds tremendous opportunity for an augmenting of programming and systems thinking. 

In most connectivity studies, roads, which represent as much as 30% of the urban land base, are viewed as an impediment and are seldom studied for the possible benefits they could provide if properly designed.  However, studies in Europe, New Zealand, Australia, the United States and Canada support the premise that planted roadside verges create valuable habitat for song birds, butterflies, bees, reptiles, insects, small mammals, and amphibians. Road rights of way as narrow as 1-5 metres are used as foraging ground, for nesting, breeding, and movement between larger habitat patches (Forman, 2003; Noss in Hellmund et al., 2006; Rudd et al., 2002, Underhill & Angold, 2000).

Using birds as a biodiversity indicator, this project develops a transferable methodology for integrating viable ecosystems and habitats into marginalized urban spaces to augment quality and connectivity across scales. Road rights of way in the Hyland Creek Watershed in Surrey, British Columbia are used as case studies to explore the integration of avian habitat, ecological function, and human programming as connective conduits. The project investigates the application of these layers through a variety of landscape types including suburban, urban, rural and industrial.

Relationships Investigated & Methods of Inquiry Used
A literature review focused on case studies, design precedents and scientific studies was undertaken to support the premise that road rights of way of various sizes and contexts are appropriate spaces for supporting a variety of habitat needs, and to help establish design principles aimed at other ecological functions, and human programming.

The subsequent methodology of this project proceeded in two parallel streams. The first was in the creation of locally specific habitat models for nine indicator species. The presence of an indicator species indicates the presence of a set, or guild, of other species. Inversely, the absence of an indicator species suggests the absence of the rest of the guild. Indicator species are not always seen as reliable at multiple scales, so in addition to designing for selected indicator species, the project pays explicit attention to the ecological processes that support them through the modeling of optimal ecosystem conditions. These were used to inform the development of appropriate roadside habitat types that could function in linear configurations and could be exposed to right of way conditions.

The second stream of inquiry was one of site analysis. Using an existing low resolution regional connectivity study (Axys, 2006) as a base map, ecosystem types were specified through the use of aerial photographs and field checking. This was followed up at a closer scale that included the watershed selected for design and a two kilometer buffer around it. Both scales included the mapping of potential migration routes and highlighted potential areas for design by identifying areas of critical fragmentation. Available habitat area was determined using available GIS data, hand mapping, and precedents of road narrowing measures.

Results of Research
The knowledge attained in the literature review, modeling and site analysis was used to develop a habitat designation process. Although this process appears linear, it was the result of a number of iterations of modeling, analysis, site analysis and site design. Selected site designs were used to test and simplify the resulting transferable habitat designation process.

The literature review confirmed that despite their role in habitat fragmentation, roads are also a potential avenue for restoring connectivity in an intensive landscape. The continuous nature of road verges is valuable in connecting remnant habitat patches in intensified or modified landscapes. The scale of road right of way appears to best accommodate birds, insects, fish and possibly small mammals, but the general ecosystem health of these spaces may additionally positively influence other species.

Modeling
Birds were selected for locally specific rationale and due to general theory of birds and biodiversity. The combination of the site's critical position on the pacific flyway and Surrey's position within the Georgia Depression Ecoprovince, which has the fastest rate of avian decline in Canada, makes the protection, management and creation of bird friendly habitat very important in this location. A far more transferable rationale is found in the importance of avian biodiversity as a benchmark for total biodiversity. Bird decline is often considered to be a bioindicator for general problems within an ecosystem and as a surrogate measure for overall biodiversity (Haskell 2003 in Mooney, 2007 unpublished). In addition to information on which landscape types are preferred for a variety of day to day avian activities, species modeling highlighted the symbiotic spatial relationship between humans and birds.

Species and ecosystem modeling resulted in fourteen types of landscapes. As many shared key characteristics, these were grouped into five linear, roadside appropriate habitat types.

Available Habitat Area
There are a number of roads within the Hyland Creek watershed, the design site for this project. This project focused on collector and arterial streets. They are the most connective, create the biggest fragmentation impact and offer the widest design spaces for possible habitat integration.  In this community there is typically 3-7m per side of a collector or arterial street that could be dedicated as available habitat space or area.  In many cases traffic lanes are wide, so using a standard of 3.35m per lane, dubbed "the road diet" (Burden et al, 1999) and applied in Toronto and New York, roads become safer places and afford larger available habitat width of 4 to 10m. Block sizes of collector and arterial streets are 800m in length in this community,  resulting in between 5400 and 16000m² of available habitat space for each linear block, even accounting for sidewalks, driveways and local streets. As a reference point, a Canadian football field is 8000m². This is a significant amount of available linear habitat, especially when applied across a large landscape.   

Habitat Designation Process
This information culminated in the development of a step by step habitat designation process. This process, detailed on the attached pages, leads to more informed site scale habitat design and decision making and could be applied to any site, not only to road rights of way.

Conclusions Concerning the Significance of the Results and Comparisons with Past Research
This project makes two significant contributions to the existing body of knowledge:  a methodology, and a design precedent. As mentioned in the narrative, there has been significant theoretical work in the area of landscape ecology, a discipline that focuses on the "structural pattern of a landscape or region" (Dramstad et al., 1996). This project offers an example of fine grained transferable landscape architecture work within the context of landscape ecology principles, illustrating the use of locally specific species and ecosystem modeling.

The literature review suggests that in contemporary landscape architecture there is a growing body of work on altering typical "gray" roads to "green" streets. Even when habitat is included in goal statements there are either no specific habitat creation actions taken, or they are very general and are not site or region specific.  Scientific research supports the premise that road rights of way as narrow as 1-5 metres are used as foraging ground, for nesting, breeding, and movement between larger habitat patches. This project provides site and community scale examples of street designs with both explicit human and habitat goals. The primary significance of this research is that it led to the development of a site specific habitat designation methodology. If applied, this could significantly increase the quality and quantity of viable habitat area, which could considerably strengthen a community's role in maintaining biodiversity across scales.

Applicability to Landscape Architecture Practice 
The proposed methodology offers a user friendly tool to increase the habitat potential of marginalized spaces in the developed landscape and as a result, the potential for a much greener public realm. This methodology allows for landscape architects without specializations in ecology to make more informed decisions. It will increase the level of detail typically employed, going beyond generalized spatial patterns and guidelines to a community and site specific habitat creation approach. This will result in site and context appropriate design outcomes.

Need for Further Research
Specific habitat impacts can only be known through the implementation of these designs and ongoing assessment of the sites.  Measuring success over a period of several years and implementing this approach at a number of sites would further test the presumed transferability, reproducibility and success of this methodology. Testing this methodology in different regions with different ecosystem types and conditions would also be useful in determining the transferability of the methodology. 
 

Works Cited in this Summary
Axys Environmental Consulting ltd. (2006) "GVRD Biodiversity Framework: Assessment of Regional Biodiversity and Development of a Spatial Framework for Biodiversity Conservation in the Greater Vancouver Region"
Burden, D. & P. Lagerwey. (1999) "Road Diets: Fixing the Big Roads." Walkable Communities, Inc.
Dramstad, W., J. Olson & RTT Forman (1996) "Landscape ecology principles in landscape architecture and land use planning" Washington: Island Press.
Forman, Richard, T.T et al. (2003). "Road Ecology: Science and Ecology." Washington, DC: Island Press.
Mooney P.F. 2008 "A general model of avian biodiversity" Unpublished PhD dissertation University of Michigan School of Natural Resources and Environment.
Hellmund P.C. and D.C. Smith (2006). "Designing Greenways: Sustainable landscapes for Nature and People".
University of Minnesota Press: Minneapolis, MN.
Rudd, H., J.Vala & V. Schaefer. (2002) "Urban Biodiversity: Exploring Natural Habitat and its Value in Cities. " Douglas College Centre for Environmental Studies and Urban Ecology
Underhill, J. & P. Angold. (2000) "Effects of roads on wildlife in an intensively modified landscape" Environ. Rev. (8) pp21-39.