Bird records and habitat covariates databases (11 species; Oaxaca 2016-2018)
Data files
Mar 28, 2021 version files 544.74 KB
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DBbirds.csv
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DBcovs.csv
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README.txt
Abstract
Assessing the impact of working landscapes on biodiversity and defining locally contextualized management guidelines for productive activities are key for sustainability. Occupancy dynamics provide information about sites in the landscape that are either avoided or preferred by populations through the estimation of extinction and colonization probabilities, respectively. We identified the habitat traits that affected colonization and extinction probabilities of target birds (forest-dependent, endemic, or conservation-concern species) within a Neotropical working landscape by using multi-season occupancy models to point-count data collected through a participatory monitoring approach, and considering our imperfect detectability of species in the field. We provided colonization and extinction scenarios according to local land uses (forestry plots, urban-cropfield areas, conservation forests) to recommend management activities that could have a positive impact on bird conservation. Shrub cover was key for local colonization of most of our focal species. Increasing values of tree size and tree species richness can enhance microhabitat complexity, which in turn promotes the presence of arboreal birds. Selective forestry management, in which only the largest individuals of a few tree species are extracted, promoted high colonization rates of birds because the structure of the vegetation remains relatively unaffected. In contrast, intensive forestry management plots, in which most trees are removed, resulted detrimental for bird occupancy. Local management guidelines should pay special attention to maintaining shrub cover, tree size, and tree species richness above critical values (>50%, >30 cm, > 7 tree species, respectively) to promote habitat use by birds in this type of working landscapes.
Methods
Habitat traits: We measured eight environmental features that may affect bird occurrence at each point count station to determine the functional relationship between habitat traits and the dynamics of bird occupancy: tree species richness, tree density, average tree diameter at breast height, average arboreal height, percent tree cover, shrub species richness, percent shrub cover, and altitude. The relevance of our habitat traits for forestry activities was determined with the advice of local forestry technicians. A single observer visually estimated all vegetation cover variables. We calculated average values for tree diameter at breast height and arboreal height by measuring trees located at the center and at the four cardinal points of each bird count station.
Bird surveys: To account for inter-annual and seasonal variability in bird occupancy, we performed five sampling events from 2016 to 2018, which included three winters (January-February) and two summers (June). We surveyed birds in 151 point count stations separated by a minimum distance of 200 m to ensure independent data. We located point count stations following a spatially-balanced sampling design, distributing their number proportionally to the surface covered by each land use across the study site (i.e., 30 stations for C, 10 stations for IM, 48 stations for SM, 25 stations for FS, 38 stations for U-C). Birds were surveyed during a four-hour period beginning at sunrise to cover their peak activity. We recorded all heard or seen bird individuals within 10-min fixed-radius (30 m) point counts. During each sampling season, point count stations were repeatedly surveyed (six replicates per site) by three independent observers who simultaneously counted birds. From the total pool of species, we selected a diverse group of 11 target species, including the Amethyst-throated Hummingbird (Lampornis amethystinus), the Bumblebee Hummingbird (Atthis heloisa), the Spot-crowned Woodcreeper (Lepidocolaptes affinis), the Brown Creeper (Certhia americana), the Brown-backed Solitaire (Myadestes occidentalis), the Russet Nightingale-Thrush (Catharus occidentalis), the Ruddy-capped Nightingale-Thrush (Catharus frantzii), the Olive Warbler (Peucedramus taeniatus), the Chestnut-capped Brushfinch (Arremon brunneinucha), the Golden-browed Warbler (Basileuterus belli), and the Red Warbler (Cardellina rubra).
Usage notes
Data is comprised of both habitat covariates and bird records. Study site was located in Oaxaca, southern Mexico. We used this data to perform multi-season occupancy models, in order to determine bird habitat use across a working landscape where forestry is the main productive activity.