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Billions of wild animals migrate every year between breeding and non-breeding sites, facing new environmental conditions due to anthropogenic change. Although cities engender profound environmental changes, they provide habitat for some migratory birds contributing to conserving biodiversity and restoring human-nature connections. A common issue in Neotropical cities is their socio-environmental segregation, that might result in wealthier people having access to greater biodiversity in their neighborhoods. Although growing evidence shows a relationship between wealth and biodiversity in cities, it remains poorly investigated in relation to animals, particularly migratory birds. We present the first study on the effects of socioeconomic status on a Neotropical austral migrant considered a keystone species. We tested whether neighborhood socioeconomic category and habitat variables relate to the occurrence of the Green-backed Firecrown hummingbird in its overwintering habitat in urban areas. We hypothesized that higher socioeconomic status of neighborhoods would positively influence hummingbird occurrence through mediating effects of woody plant cover. We found that hummingbird occurrence increased with socioeconomic level of neighborhoods and woody cover. Specifically, we found that socioeconomic level influenced hummingbird occurrence indirectly through woody and shrub cover. We also found a direct effect of socioeconomic level on hummingbird occurrence suggesting the need for further research. Our findings show that wealthier neighborhoods exhibit greater woody cover and higher hummingbird occurrence than poorer neighborhoods, providing dissimilar opportunities to experience nature close to home. In neighborhoods where people of lower socioeconomic status live, strategies aiming to increase tree and shrub cover will promote a more environmentally just city.

RESUMEN El limitado número de investigaciones ecológicas en ecosistemas urbanos de Latinoamérica dificulta manejar las áreas urbanas para la conservación de biodiversidad. Además, la mayoría de los estudios ecológicos en ciudades se han enfocado en parques y plazas, ignorando la mayor parte del ecosistema urbano. Para brindar evidencia científica robusta que permita contribuir al manejo del hábitat urbano para la conservación de aves, investigamos la influencia de variables del hábitat sobre la abundancia de especies de aves nativas y exóticas en la ciudad de Santiago, Chile. Durante la temporada reproductiva de 2017-2018, evaluamos aves y variables del hábitat en 455 puntos distribuidos a través de la ciudad. Ajustamos modelos lineales generalizados para evaluar la influencia de variables del hábitat sobre la abundancia de las especies de aves. En 905 conteos realizados, registramos 35 especies de aves (31 nativas y 4 exóticas). La abundancia de aves nativas (tórtola, fío-fío, chercán, zorzal, chincol y mirlo) aumentó con la cobertura de vegetación leñosa. Puntos con mayor cobertura arbustiva en el microhábitat exhibieron una mayor abundancia de zorzal, chincol y fío-fío. Opuesto a la respuesta de las aves nativas, la abundancia de las especies exóticas (paloma y gorrión) disminuyó con el aumento de la vegetación. Nuestros resultados demuestran la importancia de la vegetación leñosa para conservar especies de aves nativas en Santiago. Estrategias de manejo que (1) eviten la pérdida de vegetación leñosa e (2) incrementen árboles y arbustos en áreas urbanas carentes de cobertura vegetal promoverían una mayor abundancia de aves nativas. ABSTRACT A paucity of ecological research in urban ecosystems in Latin America limits the management of urban areas for biodiversity conservation. In addition, the majority of previous ecological studies in cities have focused on parks, ignoring most part of urban ecosystems. To provide robust scientific evidence for the management of urban areas for bird conservation, we investigate the influence of habitat variables on the abundance of native and exotic bird species in Santiago, Chile. During the reproductive season of 2017-2018, we surveyed birds and habitat variables at 455 points distributed throughout the city. We fit generalized linear models to evaluate the influence of habitat variables on individual bird species abundance. In 905 bird counts, we recorded 35 bird species (31 native and 4 exotic). The abundance of©2019 The author(s). Gayana ©2019 Universidad de Concepción. This open access article is distributed under the terms of the Creative Commons Attribution-NonCommercial native birds (Zenaida auriculata, Elaenia albiceps, Troglodytes aedon, Turdus falcklandii, Zonotrichia capensis and Molothrus bonariensis) increased with woody vegetation cover. Points with greater shrub cover in the microhabitat exhibited a greater abundance of T. falcklandii, Z. capensis and E. albiceps. In contrast to the response of native birds, the abundance of exotic species (Columba livia and Passer domesticus) decreased with vegetation cover. Our results demonstrate the importance of woody vegetation to conserve native bird species in Santiago. Management of habitat that (1) avoids the loss of woody vegetation and (2) aims to increase trees and shrubs in urban areas with low vegetation cover will promote a greater abundance of native birds.