Racist U.S. housing policy impacts bird biodiversity data

Study finds absence of bird data was more closely related to 1933 redlining maps than climate or tree cover

WASHINGTON – A discriminatory housing practice from the 1930s, known as redlining, is affecting bird biodiversity data in urban areas in the United States.

Redlining was a system in which neighborhoods were ranked for real estate investment based on racial composition.

Neighborhoods that were predominantly Black or brown were often classified as “redlining,” which meant that they were considered high-risk investments and were ineligible for loans and other financial assistance.

This history of discrimination has led to a data gap in avian biodiversity research.

A study by Yale College ecologist Diego Ellis-Soto found that areas that were redlined in the 1930s had far less bird survey data than areas that were not redlined.

Ellis-Soto’s study, for example, found that more than half a million bird observations were recorded on the Yale campus during the past century.

“You can better predict where you have data on birds based on systemic racism — redlining maps from 1933 — than climate, tree cover or population density, everything a bird should actually care about,” he said.

 By contrast, in the nearby Dixwell neighborhood, which is predominantly Black.

This discrepancy suggests that racial bias has had an unintended effect on the collection of bird data.

Ellis-Soto’s study also found that the presence or absence of bird data was more closely related to the 1933 redlining maps than to factors such as climate or tree cover.

Areas with less bird data are more likely to be overlooked for funding and protection, which could perpetuate historical inequities.

This study is a groundbreaking examination of the role of racism in ecological processes.

It underscores the need to address the legacy of redlining and other forms of discrimination to create a more equitable future for all.

The study is one of the first direct looks at how “systemic racism can play a role in the ecological process”, says Jin Bai, an urban ornithologist at North Carolina State University in Raleigh.