LB 41-351 - Here We Go Again: Urban Case Studies on the Impacts of Racist Urban Policy on Avian Communities

Only recently have we begun to understand the extent to which racist development practices like redlining impact patterns of biodiversity in cities. It is critical to consider the history of a city holistically and investigate how not just environmental factors but also social ones affect biodiversity. While redlining in particular may have a large impact on neighborhoods, there are also other key social factors to consider. We performed preliminary case studies on 3 US cities: St. Louis, San Francisco, and Boston. We chose these specific cities to achieve a range of different sizes, geographic location, and population size. We focused on highways, single-family zoning, distribution of greenspaces, and distance to railroads, all of which have been shown to contribute to racial and income segregation. To look at wildlife biodiversity, we use eBird citizen science data to look at how birds have responded to these factors in addition to the distribution of greenspaces and vegetation index using Shannon’s Diversity Index, Simpson’s, and species richness.We use these various factors to ask the following: 1. How do cities differ from each other in terms of biodiversity? 2. What are the major covariates that impact biodiversity in each of the different cities? We found that overall there was a non-significant difference between cities in terms of biodiversity for Shannon’s Diversity or Simpson’s. In terms of species richness, we found that San Francisco had the highest number of species (157), followed by St. Louis (146) and Boston (132). In San Francisco, the only significant covariate in our model was distance from highways, which had a positive relationship with biodiversity. In Boston and St. Louis, both highways and closeness to greenspace had positive significant relationships with biodiversity. We found that St. Louis had the largest number of highways intersecting the city (about 24) with Boston having 9 and San Francisco having 3. Overall, we found that San Francisco had the most greenspaces (NDVI was about 30% more than both St. Louis and Boston) and the highest relative species abundance. This initial study suggests that how many greenspaces and highways a city has may impact bird biodiversity and as a next step we hope to scale up to 30 cities to achieve a more robust analysis.