Abstract The Dominican Republic is experiencing increased forest loss due to the expansion of avocado farming. While agricultural lands can provide viable habitat for birds, knowledge of avian use of avocado farms relative to native forest is limited. We conducted surveys in fall 2021 to compare the bird communities and vegetation complexity of two avocado farm sites and two native dry forest sites in the northern Sierra de Bahoruco region of the Dominican Republic to assess avian habitat use. Overall, we found that habitat associations differed for bird species distinguished by contrasting geographic ranges. In particular, the abundance, richness, and diversity of bird species endemic to Hispaniola were significantly greater in forests than in farms, while non-endemic resident bird species had the opposite habitat associations. The abundance, richness, and diversity of Neotropical migrants exhibited fewer distinct differences between farm and forest sites. Vegetation structural complexity was reduced in avocado farms relative to forests and was positively associated with the abundance, richness, and diversity of endemic bird species but negatively associated with these community measures of non-endemic resident species. Collectively, our findings suggest that avocado farms could provide viable habitat for non-endemic resident and migrant bird species, but that endemic species could be negatively impacted by an increase in avocado farming in the region. We offer recommendations for forest preservation, farming practices, and future research that could help to inform the conservation of endemic species in the region. Keywords agriculture, avian conservation, Dominican Republic, endemic species, habitat use, land-use change, Neotropical migrants Resumen Uso de granjas de cultivo de aguacate y bosques nativos por parte de las aves en el norte de la Sierra de Bahoruco, República Dominica • La República Dominicana está experimentando una mayor pérdida de bosques nativos como consecuencia de la expansión de los cultivos de aguacate. Aunque las tierras agrícolas pueden proporcionar un hábitat propicio para algunas aves, el conocimiento sobre el uso que hacen de los cultivos de aguacate en comparación con las áreas forestales nativas es limitado. En otoño de 2021, realizamos muestreos en dos granjas de aguacate y dos bosques secos nativos en la región norte de la Sierra de Bahoruco (República Dominicana), y comparamos las comunidades de aves y la complejidad de la vegetación para evaluar el uso del hábitat que hacen las aves. En general, observamos diferencias entre las asociaciones de hábitats de las especies de aves con distribuciones geográficas distintas. En particular, la abundancia, riqueza y diversidad de especies de aves endémicas de La Española fueron significativamente mayores en los bosques que en las granjas; mientras que las especies de aves residentes no endémicas mostraron asociaciones de hábitat opuestas. La abundancia, riqueza y diversidad de las aves migratorias neotropicales exhibieron menos diferencias entre las granjas y los bosques. La complejidad estructural de la vegetación se redujo en las granjas de aguacate en relación con los bosques y tuvo una correlación positiva con la abundancia, riqueza y diversidad de aves endémicas, pero negativa con las mismas medidas comunitarias de especies residentes no endémicas. En conjunto, nuestros resultados sugieren que los cultivos de aguacate podrían proporcionar un hábitat adecuado para aves residentes no endémicas y migratorias; mientras que las especies endémicas podrían verse afectadas negativamente por un aumento de estos cultivos en la región. Por último, proporcionamos recomendaciones para la conservación de los bosques, prácticas agrícolas y futuras investigaciones que podrían contribuir a la conservación de las aves endémicas de esta región. Palabras clave agricultura, aves migratorias neotropicales, cambio de uso de suelo, conservación de aves, especies endémicas, República Dominicana, uso de hábitat Résumé Utilisation par les oiseaux des plantations d’avocatiers et des forêts non exploitées dans le nord de la Sierra de Bahoruco, en République dominicaine • En République dominicaine, la forêt indigène est en régression en raison de l’augmentation de la culture des avocatiers. Bien que les terres agricoles puissent fournir un habitat approprié à certains oiseaux, les connaissances sur l’utilisation des plantations d’avocatiers par rapport à celle des forêts indigènes sont limitées. Nous avons échantillonné deux plantations d’avocatiers et deux forêts sèches indigènes dans la Sierra de Bahoruco (République dominicaine) au cours de l’automne 2021, et nous avons comparé leurs communautés d’oiseaux et la complexité de leur végétation afin d’évaluer l’utilisation de ces deux habitats par les oiseaux. Dans l’ensemble, nous avons observé que les associations entre espèces d’oiseaux et habitats différaient en fonction de la répartition géographique des oiseaux. En particulier, l’abondance, la richesse et la diversité de l’avifaune endémique à Hispaniola étaient significativement plus fortes dans les forêts que dans les plantations, tandis que les espèces d’oiseaux sédentaires non endémiques étaient inversement associées à ces habitats. L’abondance, la richesse et la diversité des migrateurs néotropicaux présentaient moins de différences distinctes entre les milieux agricoles et forestiers. La complexité de la structure de la végétation était plus faible dans les plantations d’avocatiers que dans les forêts, et était positivement corrélée à l’abondance, à la richesse et à la diversité des espèces d’oiseaux endémiques, mais négativement corrélée à ces mesures pour les communautés d’espèces sédentaires non endémiques. Dans l’ensemble, nos résultats semblent indiquer que les plantations d’avocatiers pourraient constituer un habitat viable pour les espèces d’oiseaux sédentaires et migrateurs non endémiques, mais que les espèces endémiques pourraient être affectées négativement par une augmentation de ces cultures dans la région. Nous formulons des recommandations pour la préservation des forêts, les pratiques agricoles et les recherches futures qui pourraient contribuer à la conservation des espèces endémiques dans la région. Mots clés agriculture, changement d’affectation des terres, conservation de l’avifaune, espèces endémiques, migrateurs néotropicaux, République dominicaine, utilisation des habitats
Species differ in vulnerability to anthropogenic land use changes. Knowledge of the mechanisms driving differential sensitivity can inform conservation strategies but is generally lacking for species‐rich taxa in the tropics. The diverse bat fauna of Southeast Asia is threatened by rapid loss of forest and expanding agricultural activities, but the associations between species, traits, vulnerability to agriculture, and the underlying drivers have yet to be elucidated. We studied the responses of speciose insectivorous bat assemblages to robusta coffee cultivation in Sumatra, Indonesia. We compared abundance, species richness, and assemblage structures of bats between forests and coffee farms based on trapping data and evaluated the influence of vegetation complexity on assemblage composition and species‐level reactions. Bat abundance and species richness were significantly lower in coffee farms than in forests. Bat assemblage structure differed between land uses, and the overall variation can be largely explained by vegetation simplification. Species sensitive to coffee agriculture were associated with more complex vegetation structure, whereas tolerant species were associated with simpler vegetation structure. Sensitive and tolerant species differed in the type, frequency, and bandwidth of echolocation calls and roost use. Species sensitive to coffee use broadband and high‐pitched frequency‐modulated calls, which are efficient at detecting insects in complex vegetation, and roost in plant structures that may be lost as vegetation is simplified. In contrast, tolerant species used lower pitched constant‐frequency calls and roost in caves. We advocate for greater use of trait analyses in studies seeking to clarify the influence of agriculture on diverse tropical bat faunas.
Abstract in Indonesian is available with online material.
more » « less- NSF-PAR ID:
- 10460330
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Biotropica
- Volume:
- 51
- Issue:
- 5
- ISSN:
- 0006-3606
- Page Range / eLocation ID:
- p. 757-768
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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