Historical racial redlining and contemporary patterns of income inequality negatively affect birds, their habitat, and people in Los Angeles, California

The Home Owners' Loan Corporation (HOLC) was a U.S. government-sponsored program initiated in the 1930s to evaluate mortgage lending risk. The program resulted in hand-drawn "security risk" maps intended to grade sections of cities where investment should be focused (greenlined areas) or limited (redlined zones). The security maps have since been widely criticized as being inherently racist and have been associated with high levels of segregation and lower levels of green amenities in cities across the country. Our goal was to explore the potential legacy effects of the HOLC grading practice on birds, their habitat, and the people who may experience them throughout a metropolis where the security risk maps were widely applied, Greater Los Angeles, California (L.A.). We used ground-collected, remotely sensed, and census data and descriptive and predictive modeling approaches to address our goal. Patterns of bird habitat and avian communities strongly aligned with the luxury-effect phenomenon, where green amenities were more robust, and bird communities were more diverse and abundant in the wealthiest parts of L.A. Our analysis also revealed potential legacy effects from the HOLC grading practice. Associations between bird habitat features and avian communities in redlined and greenlined zones were generally stronger than in areas of L.A. that did not experience the HOLC grading, in part because redlined zones, which included some of the poorest locations of L.A., had the highest levels of dense urban conditions (e.g., impervious surface cover), whereas greenlined zones, which included some of the wealthiest areas of the city, had the highest levels of green amenities (e.g., tree canopy cover). The White population of L.A., which constitutes the highest percentage of a racial or ethnic group in greenlined areas, was aligned with a considerably greater abundance of birds affiliated with natural habitat features (e.g., trees and shrubs). Conversely, the Hispanic or Latino population, which is dominant in redlined zones, was positively related to a significantly greater abundance of synanthropic birds, which are species associated with dense urban conditions. Our results suggest that historical redlining and contemporary patterns of income inequality are associated with distinct avifaunal communities and their habitat, which potentially influence the human experience of these components of biodiversity throughout L.A. Redlined zones and low-income residential areas that were not graded by the HOLC can particularly benefit from deliberate urban greening and habitat enhancement projects, which would likely carry over to benefit birds and humans. center dot Redlining was a racially biased investment and lending practice established in the 1930s and applied in 239 cities across the United States.center dot The program was terminated in 1968 but has since been linked with strong segregation of human communities, wealth, and green amenities in cities nationwide.center dot In Greater Los Angeles, California, redlining continues to be negatively related to avian community patterns, their habitat and the people who may experience them.center dot Luxury-effect patterns, where biodiversity is positively associated with affluence, largely predicted avifaunal patterns in Greater Los Angeles center dot Legacy-effect patterns due to historical redlining also showed strong relationships and patterns of bird habitat and community composition, suggesting the practice is potentially a powerful force structuring contemporary urban avifauna and human communities.center dot Careful yet deliberate action in urban greening could likely benefit birds and humans in redlined zones and other low-income areas of Greater Los Angeles. La Corporacion de Prestamos para Propietarios de Hogares (HOLC, por sus siglas en ingles) fue un programa patrocinado por el gobierno de EEUU, iniciado en la decada de 1930, para evaluar el riesgo en la concesion de hipotecas. El programa resulto en la creacion de mapas de "riesgo de seguridad" dibujados a mano, destinados a clasificar secciones de ciudades donde la inversion deberia centrarse (areas resaltadas en verde) o limitarse (zonas marcadas en rojo). Los mapas de seguridad han sido ampliamente criticados posteriormente por ser inherentemente racistas y se han asociado con altos niveles de segregacion y niveles mas bajos de comodidades verdes en ciudades de todo el pais. Nuestro objetivo fue explorar los posibles efectos heredados de la practica de calificacion de HOLC en las aves, su habitat y en las personas que podrian experimentarlos, en toda una metropolis donde los mapas de riesgo de seguridad se aplicaron ampliamente, el Gran Los angeles, California (L.A.). Utilizamos datos recopilados en el terreno, obtenidos de forma remota y censales, junto con enfoques descriptivos y de modelado predictivo, para abordar nuestro objetivo. Los patrones de habitat de las aves y de las comunidades de aves se alinearon fuertemente con el fenomeno del efecto de lujo, en el que las comodidades verdes fueron mas solidas y las comunidades de aves fueron mas diversas y abundantes en las partes mas ricas de L.A. Nuestro analisis tambien revelo posibles efectos heredados de la practica de calificacion de HOLC. Las asociaciones entre las caracteristicas del habitat de las aves y las comunidades de aves en las zonas marcadas en rojo y verde fueron generalmente mas fuertes que en las areas de L.A. que no experimentaron la calificacion de HOLC, en parte porque las zonas marcadas en rojo, que incluian algunas de las ubicaciones mas pobres de L.A., tuvieron los niveles mas altos de condiciones urbanas densas, como la cobertura de superficie impermeable, mientras que las zonas marcadas en verde, que incluian algunas de las areas mas ricas de la ciudad, tuvieron los niveles mas altos de comodidades verdes, como la cobertura de dosel arboreo. La poblacion blanca de L.A., que constituye el mayor porcentaje de un grupo racial o etnico en las areas resaltadas en verde, se correspondio con una abundancia considerablemente mayor de aves afiliadas a caracteristicas de habitat natural (e.g., arboles y arbustos). Por el contrario, la poblacion hispana o latina, que es dominante en las zonas marcadas en rojo, estuvo relacionada positivamente con una abundancia significativamente mayor de aves sinantropicas, que son especies asociadas con condiciones urbanas densas. Nuestros resultados sugieren que la discriminacion historica en la delimitacion de zonas y los patrones contemporaneos de desigualdad de ingresos estan asociados con comunidades de avifauna distintas y con sus habitats, lo que potencialmente influye en la experiencia humana de estos componentes de la biodiversidad en todo L.A. La delimitacion de zonas marcadas en rojo y las areas residenciales de bajos ingresos que no fueron calificadas por HOLC pueden beneficiarse especialmente de proyectos dirigidos al enverdecimiento urbano y a la mejora de habitat, que probablemente a su vez beneficiaran a las aves y los humanos.