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
As climate change increases the frequency and severity of droughts in many regions, conservation during drought is becoming a major challenge for ecologists. Droughts are multidimensional climate events whose impacts may be moderated by changes in temperature, water availability or food availability, or some combination of these. Simultaneously, other stressors such as extensive anthropogenic landscape modification may synergize with drought. Useful observational models for guiding conservation decision‐making during drought require multidimensional, dynamic representations to disentangle possible drought impacts, and consequently, they will require large, highly resolved data sets. In this paper, we develop a two‐stage predictive framework for assessing how drought impacts vary with species, habitats and climate pathways.
Central Valley, California, USA.
We used a two‐stage counterfactual analysis combining predictive linear mixed models and N‐mixture models to characterize the multidimensional impacts of drought on 66 bird species. We analysed counts from the eBird participatory science data set between 2010 and 2019 and produced species‐ and habitat‐specific estimates of the impact of drought on relative abundance.
We found that while fewer than a quarter (16/66) of species experienced abundance declines during drought, nearly half of all species (27/66) changed their habitat associations during drought. Among species that shifted their habitat associations, the use of natural habitats declined during drought while use of developed habitat and perennial agricultural habitat increased.
Our findings suggest that birds take advantage of agricultural and developed land with artificial irrigation and heat‐buffering microhabitat structure, such as in orchards or parks, to buffer drought impacts. A working lands approach that promotes biodiversity and mitigates stressors across a human‐induced water gradient will be critical for conserving birds during drought.
- NSF-PAR ID:
- 10493869
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Diversity and Distributions
- Volume:
- 30
- Issue:
- 5
- ISSN:
- 1366-9516
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Location North America.
Time period 2012–2100.
Major taxa studied Ground beetles (Carabidae).
Methods We synthesized the abundance and trait data for 136 species from the National Ecological Observatory Network (NEON) and additional raw data from studies across North America with remotely sensed habitat characteristics in a generalized joint attribute model. Combined Light Detection and RAnging (LiDAR) and hyperspectral imagery were used to derive habitat at a continental scale. We evaluated climate risks on the joint response of species and traits by expanding climate velocity to response velocity given habitat change.
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