Stage 2: Ideal Habitat Locations
Methodology
Goal 2: Where in Vancouver will birds likely be drawn to? In this urban environment, what conditions will favour bird populations the most?
For the following stage of the project, a majority of the procedures were produced using ArcMap. Here, I developed parameters to create a habitat suitability surface to identify where in the city birds are generally best suited to thrive in.
I assumed the following criteria when generalizing bird traits:
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Birds will have a better chance of survival where buildings are shorter in height. Open spaces and low buildings would likely mean that a lower building collision rate. High-rise buildings ( >10 stories tall) were designated as being detrimental to bird health.
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Regions located near existing parks and greenways would be more suitable. These areas would provide similar habitats, food sources and space to interact in as their natural environments.
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Neighbourhood blocks that have a high proportion of trees would also increase survivability of birds. Like the parks and greenways, trees would provide refuge from predators and a natural corridor path to travel along.
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Birds will prefer areas that are further away from roads and skytrain lines. This would lower the amount of fatal accidental vehicle mortalities
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Neighbourhoods with a lower population density will likely mean there are fewer disturbances and fewer domesticated cats in the area
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Zones that are designated for industrial uses are bad for birds and will have higher pollution rates
With these core guidelines in place I followed these steps to conduct my analysis:
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Import Data into ArcMap and then begin processing the data
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Data Preparation
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I first merged Lanes, One way Streets, Non-city Roads and Rapid Transit Lines to form one major road network later
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Then categorized building footprints by average height (ie. into mid-rise, high-rise developments, etc)
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Manually edited the neighbourhood block attribute table to include area and population > and then calculated population density
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Joined city trees point layer into neighbourhood blocks and then edited the attributes table to calculate tree density
3. Euclidean Distance Tool
I then performed a Euclidean Distance tool to create the following raster layers which were then reclassified with appropriate weights:
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Major Roads Network
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Parks
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Greenways
4. Next I converted the remaining layers into raster files and then reclassified their values to match what the conditions outlined for the habitat suitability analysis.
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Building Heights were reclassified as 0 - 4 (4 being anything under 5m tall)
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Zoning Regions were classified as 0 (High or Low level Industrial) or 1 (other)
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Neighbourhood Population Densities
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Neighbourhood Tree Densities
With all the information in place I performed a weighted sum tool with the following weighting schemes:
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Sensitivity Analysis (using relatively even weights)
Variables: 0.15 - Building heights
0.15 - Neighbourhood population density
0.1 - Euclidean distance to the major roads network
0.15 - Neighbourhood tree density
0.2 - Euclidean distance to parks
0.2 - Euclidean distance to greenways
0.05 - Zoning
2. Relative Weighting System (which favoured parks, greenways and building heights)
Variables: 0.2 - Building heights
0.1 - Neighbourhood population density
0.1 - Euclidean distance to the major roads network
0.1 - Neighbourhood tree density
0.2 - Euclidean distance to parks
0.2 - Euclidean distance to greenways
0.1 - Zoning
Once this analysis on the general bird population in Vancouver was complete I then performed a modified weighting system that was modelled specifically to the Predator Birds category. In this case I reclassified the building heights raster later and flipped the weighting scheme to reflect their preference of taller buildings which could be used to survey prey closer to the ground.

