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Values for area of all occupied habitat were only obtained for species whose occupancy models predicted a marked proportion of the species' population was likely present in non-forest habitats.
Values for area of occupied habitat by each species were obtained as the predicted occupied proportion of each 900 square meter pixel (i.e., occupancy probability x 900) for all habitats, except permanent water, within the Mississippi Alluvial Valley Bird Conservation Region.
Values for area of sustainable forest habitat for each species were obtained as the predicted occupied proportion of each 900 square meter pixel (i.e., occupancy probability x 900) within all forest patches deemed large enough to harbor a sustainable population of the species. The area required for a sustainable population of each species was derived from credible intervals associated with population trends from historical (1966-2015) BBS data (Sauer and others, 2017). For each silvicolous bird species in the Mississippi Alluvial Valley, we assumed the minimum sustainable population was the number of birds needed to ensure ≤1% probability that the population would be extirpated (i.e., drop below a quasi-extinction...
Values for predicted probabilities of avian species occupancy were determined using colonization-extinction models (MacKenzie and others, 2003) as implemented in R (Version 3.4.4; https://www.r-project.org/) via the ‘colext’ function of the Unmarked package (Version 0.12-0; Fiske and Chandler 2011). Performance of a null model (without covariates) and 153 additional models that assessed the effects of geographic coordinates and habitat context covariates were evaluated using Akaike information criteria (AIC; Burnham and Anderson, 2002). When more than one model had substantial support, their respective model weights were used to spatially predict occupancy relative to covariate influence. Predictive model covariates...
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