Short Communications The Wilson Journal of Ornithology 135(1):000–000, 2023 DOI: 10.1676/22-00055 The standing dead: Importance of snags for cavity-nesting birds in tropical periurban forests Rafael Rueda-Herna ´ndez, 1,2 Angelina Ruiz-Sa ´nchez, 3 Ian MacGregor-Fors, 4 and Katherine Renton 5 * ABSTRACT—Forested periurban areas represent a major asset for conservation as these sites could potentially mitigate the effects of landscape modification. Nevertheless, these forests face unsupervised management, affecting availability of resources such as tree cavities used by cavity-nesting vertebrates. We evaluated the ecological importance of snags for cavity-nesting birds in 3 periurban cloud forest remnants with different management regimes, degree of protection, and size in Veracruz, Mexico. We compared snag and cavity availability, traits, and density of primary and secondary cavity-nesting birds in 3 forested sites with different sizes and degree of disturbance. We found no snags and low cavity density in the smaller fragments, as well as lower species richness and density of cavity-nesting birds. Most suitable cavities were excavated by woodpeckers in snags, and were located in the largest forest remnant, where we also recorded the highest abundance of snags, excavators, and the highest richness of secondary cavity-nesters. Our results suggest a synergy of snag availability, primary excavators, and richness of secondary cavity-nesters in cloud forest fragments. Furthermore, simple actions, such as snag removal and/or firewood extraction, which are common activities in small forest fragments, can alter the composition of cavity-nesting assemblages with uncertain further ecological impacts. Received 25 May 2022. Accepted 8 December 2022. Key words: firewood extraction, forest management, Mexico, nesting resources, tree decay. Muertos de pie: importancia de los a ´ rboles muertos para las aves anidadoras de cavidad en bosques periurbanos tropicales RESUMEN (Spanish)—Las a ´reas boscosas periurbanas representan un activo importante para la conservaci´ on, ya que estos sitios podr´ ıan mitigar los efectos de la modificaci ´ on del paisaje. Sin embargo, estos bosques se enfrentan a un manejo sin supervisi´ on que afecta la disponibilidad de recursos como las cavidades utilizadas por los vertebrados que anidan en ellas. Evaluamos la importancia ecol´ ogica de los a ´rboles muertos en pie para las aves que anidan en cavidades en 3 remanentes periurbanos de bosque de niebla con diferentes tipos de manejo, grado de protecci ´ on y tama˜ no en Veracruz, M´ exico. Comparamos la disponibilidad y las caracter´ ısticas de las cavidades y arboles muertos en pie, adema ´s de la densidad de las aves anidadoras primarias y secundarias de cavidades en 3 sitios con diferentes tama ˜ nos y grado de perturbaci ´ on. No encontramos a ´rboles muertos en pie y hubo menor densidad de cavidades en los fragmentos ma ´s peque˜ nos, adema ´s de menor riqueza y densidad de aves que anidan en cavidades. Las cavidades ma ´s adecuadas fueron excavadas por pa ´jaros carpinteros en a ´rboles muertos, y se encontraban en el sitio ma ´s grande, donde tambi´ en registramos la mayor abundancia de a ´rboles muertos, aves excavadoras y la mayor riqueza de anidadores secundarios de cavidad. Nuestros resultados sugieren una sinergia de disponibilidad de a ´rboles muertos en pie, excavadores primarios y riqueza de anidadores secundarios de cavidad en fragmentos de bosque de niebla. Adema ´s, acciones simples, como la eliminaci´ on de a ´rboles muertos y/o la extracci´ on de le˜ na, actividades comunes en peque˜ nos fragmentos de bosque, pueden alterar la composici´ on de los ensambles de anidadores de cavidad con impactos ecol ´ ogicos futuros inciertos. Palabras clave: a ´rboles muertos, extracci´ on de madera, manejo de bosques, M´ exico, recursos de anidaci´ on. Cloud forests have one of the highest distur- bance rates among forest ecosystems worldwide, as they experience increasing negative impact from sprawling urban growth, farming, and coffee production (Doumenge et al. 1995, Williams- Linera et al. 2002). Of these, urbanization is one of the main threats to biodiversity as, in addition to other types of land-cover transformation, urban areas have long-term, direct effects on neighboring forests (Pauchard et al. 2006, Grimm et al. 2008, Gaston et al. 2010). This is particularly troubling in the Neotropics, which has high biodiversity but rising human population densities and urbanization rates (Pauchard and Barbosa 2013). Cloud forests, with their naturally fragmented distribution and high faunal endemism, may be particularly 1 Posgrado en Ciencias Biol´ ogicas, Universidad Na- cional Aut´ onoma de M´ exico, Mexico City, Mexico 2 Red de Ambiente y Sustentabilidad, Instituto de Ecolog´ ıa, A.C., Veracruz, Mexico 3 Facultad de Biolog´ ıa, Universidad Veracruzana, Veracruz, Mexico 4 Ecosystems and Environment Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Lahti, Finland 5 Estaci´ on de Biolog´ ıa Chamela, Instituto de Biolog´ ıa, Universidad Nacional Aut´ onoma de M´ exico, Jalisco, Mexico * Corresponding author: krenton@ib.unam.mx 1 Downloaded from http://meridian.allenpress.com/wjo/article-pdf/doi/10.1676/22-00055/3186954/10.1676_22-00055.pdf by Wilson Ornithological Society Member Access, RAFAEL RUEDA on 09 February 2023