Understanding How Gentrification Affects Urban Wildlife Around Us

When you live in a city, coexisting with local wildlife can come in many forms. Sometimes you’re stuck dealing with a rat in your trash bin, but other times you’re greeted in the morning by a songbird singing outside your window. This is the reality of urban wildlife in cities all over the country. They can be seen as pests or small ways to connect with nature in daily life, depending on the species and the situation. But just as these animals affect humans’ quality of life, we too have an effect on their lives and where they choose to call home in our vast cities.

Between 2019 and 2021, Lincoln Park Zoo’s Urban Wildlife Institute studied how gentrification— defined by Merriam-Webster as “the process whereby the character of a poor urban area is changed by wealthier people moving in, improving housing, and attracting new businesses, typically displacing current inhabitants in the process”—impacts where urban wildlife chooses to live and the diversity of different species in those areas. The results, published this week in Proceedings of the National Academy of Sciences of the United States of America (PNAS), give us a clearer idea of how the effects of gentrification are felt by animals, and provide further evidence of how nature is chronically inaccessible to marginalized communities living in cities.

Gentrification and How It Shapes Our Cities

To analyze the differences in urban wildlife populations in gentrified and non- gentrified parts of a city, UWI enlisted the help of its partners in the zoo’s Urban Wildlife Information Network (UWIN). UWIN is a collective of scientists, ecologists, and educators dedicated to understanding biodiversity and mitigating human-wildlife conflict in cities. In total, 36 partners in 23 cities across the continental U.S. worked to collect findings for this study, creating a dataset of North American mammal distributions that is unrivaled in its magnitude.

To generate this dataset, UWIN partners placed camera traps—a noninvasive way to collect data on animal populations—in nearly 1,000 different urban greenspaces like city parks, cemeteries, or golf courses. After combing through the millions of photos collected over three years, the analysis specifically looked at 21 widely distributed mammal species across 11 families, including various squirrels, deer, foxes, bobcats, beavers, and more.

Understanding What It All Means

After analyzing results from a wide array of urban landscapes, Fidino and his team found that gentrified parts of a city did indeed have more species present than non-gentrified parts of a city. This equated to about 1 to 2 more mammal species in gentrified locations, on average, but the magnitude of this relationship varied among cities. For example, Chicago had perhaps one of the largest associations between gentrification and species richness. Research showed that there could be 5 to 6 more mammals in gentrified parts of the city, which was one of the biggest cities included in the study. Overall, this result demonstrates that gentrification sufficiently modifies the local environment to allow for more wildlife, which in turn indicates that people across a city have varying degrees of exposure to urban nature in their daily lives.

There were also some larger scale spatial patterns UWI found between gentrification and wildlife communities within each city. In East Coast cities, for example, gentrification had a greater effect on the number of species living in an area. That means people living in gentrifying neighborhoods may regularly experience a wider array of urban wildlife. This is notable because past research has shown that exposure to nature positively affects our mental health.

In West Coast cities, on the other hand, gentrification was not often related to increases in the number of species present in an area. Instead, gentrified and not gentrified parts of a West Coast cities often had the same number of species, but the identity of those species differed. This is notable because access to wildlife isn’t as simple as saying “the more animals, the better.” Most city dwellers can attest to the fact that certain species are much more desirable to interact with than others. If more affluent communities are coexisting with songbirds and rabbits while marginalized communities are experiencing conflict with rats and raccoons, the average quality of life can still vary greatly based on such differences.

Other Factors to Consider When Looking at Urban Wildlife Diversity

It’s important to remember that gentrification isn’t the only human-made factor impacting urban wildlife. UWI’s study found that impervious cover, such as concrete, asphalt, and compacted soil, had an even greater effect on non-human animals living in cities.

A highly developed gentrified area, such as a downtown neighborhood, will still have less urban wildlife than a neighborhood with less impervious cover. For instance, Chicagoans will struggle to find a wide array of urban mammals in neighborhoods like the West Loop, despite it being a more affluent area. That’s why it’s important to ensure that there are dedicated green spaces in all urban neighborhoods, for humans and animals alike.

How Does This Impact the Future of Cities?

The findings from this study offer another piece of evidence for the larger argument that equal access to nature is integral to the health and wellbeing of any city’s population. Urban planners and city officials should push for a more equitable distribution of these green spaces that benefit residents of all socioeconomic backgrounds.

“My hope is that these results can be used to advocate for updated land development and management practices that prioritize social equity and access to nature spaces for all urban communities,” said Fidino.