Distribution Patterns of Migrant and Resident Birds in Successional Forests of the Yucatan Peninsula, Mexico¹

Abstract

Increasing human activity in the Yucatan peninsula has led to declines in older stages of successional forest, threatening regional habitat diversity. To determine potential effects of this habitat loss on the region's avifauna, we examined the relative use of different forest stages by resident and migrant birds during the nonbreeding season. We used the fixed‐width transect method to compare the distribution, abundance, and diversity of forest birds in early (five to ten years old), mid (15–25 years), and late (<50 years) successional forests in the state of Campeche, Mexico, in the south‐central part of the peninsula. All stages of successional forest had highly similar bird assemblages and did not differ in bird abundance or diversity. Both migrant and resident birds occurred across the successional gradient. The majority of habitat specialists, however, were resident birds restricted to late‐successional forest, indicating that early secondary growth may not be suitable for all species. Furthermore, resident birds that typically participate in mixed‐species flocks attained their greatest densities in the oldest forest habitat. Rapid recovery of pre‐disturbance physiognomic features, in addition to high levels of habitat connectivity in the region, may contribute to similar bird communities across a range of successional stages. The high degree of edge characterizing much of the forest mosaic also may allow birds access to different serai stages. Loss of late‐successional forest, however, is likely to adversely affect the subset of resident avifauna that depends on unique features of mature habitat such as snags, large trees, and climatic buffering. Conservation efforts in Campeche should focus on the specialized requirements of the most habitat‐restricted species while preserving the current landscape mosaic characteristic of the small‐scale shifting cultivation system. RESUMES El aumento de la actividad humana en el uso del suelo en la Peninsula de Yucatán, ha resultado en la disminución de la regeneración de la selva a etapas más maduras de sucesión, amenazando la diversidad regional de habitats. Para determinar los efectos de esta pérdida sobre la avifauna de la región, estudiamos el uso de diferentes etapas de sucesión de la selva por aves residentes y migratorias durante la temporada no reproductiva. Usamos el método de transecto linear de anchura fija para comparar la distributión, abundancia y diversidad de aves en vegetaclón sucesional (acahuales) de diferentes edades, incluyendo acahual joven (cinco a diez años de edad), acahual de edad media (15‐25 afios) y selva (>50 afios) en el sur del estado de Campeche, Mexico. Diferentes etapas de sucesión de la selva tuvieron composition de aves muy similares y no variaron en la abundancia y la diversidad. Tanto las especies migrantes como residentes, estuvieron presentes a travél del gradiente sucesional. Sin embargo, la mayoría de los especialistas fueron aves residentes restingidas a etapas más viejas de sucesión de selva, indicando que la vegeta...

Variación en la composición de comunidades de aves en la Reserva de la Biosfera Montes Azules y áreas adyacentes, Chiapas, México

“…Por otra parte, aunque se ha considerado que ambientes maduros (e.g., selvas) son muy diversos (Blake & Loiselle 2001), varios investigadores han señalado que tanto la riqueza como la abundancia y diversidad de especies es similar en etapas de sucesión tempranas y maduras (Andrade & Rubio 1994, Petit et al 1995, Smith et al 2001. Por ejemplo, los resultados aquí presentados varían de acuerdo a lo reportado por Robinson & Terborgh (1997) y Blake & Loiselle (2001) en selvas altas de Costa Rica, en donde selvas en regeneración presentaron mayor riqueza y abundancia de especies de aves que la selva madura.…”

Bird Abundances in Primary and Secondary Growths in Papua New Guinea: A Preliminary Assessment

“…This assumption is based on previous large-scale secondary studies indicating a negligible effect on bird diversity [e.g., [39][40][41][42], whereas other studies [19,43] have shown that diversity is affected in small-scale studies that do not make up a matrix of surrounding primary (or close to primary) habitats and edge habitats. While the short duration of our survey and the sampling limitations intrinsic to the sampling design used recommend caution with the interpretation of the data presented, the results suggest that shifting cultivation fallows seem to have similar abundances but different richness of bird species compared to primary forest.…”

Birds, charcoal and cattle: Bird community responses to human activities in an oak forest landscape shaped by charcoal extraction

“…We also hypothesized that the responses of resident and migratory bird species should differ in each of the management units. Resident bird species should present larger differences in their communities among management units than Neotropical migrants because they have to confront the existing habitat conditions throughout the year, while migrants can act as habitat generalists because they use different environments in different seasons (Hutto, 1989;Lynch, 1989;Levey, 1994;Smith et al, 2001).…”