Filters: partyWithName: U.S. Geological Survey (X) > partyWithName: Daniel J Twedt (X)
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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.
These data identify the time (0-1 min, 1-2 min,or 2-3 min) and distance (≤50 meters, >50 meters) category when birds were first detected during 3-minutes point counts at stop locations associated with North American Breeding Bird Survey routes or route equivalents that were surveyed on dates between 2009 and 2016 and provide point location coordinates of stop locations along North American Breeding Bird Survey routes or route equivalents within (or within 60 miles) the Gulf Coastal Plains & Ozarks Landscape Conservation Cooperative boundary.
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.
Based on forest patch area, location, and hydrologic influence, we ranked the purported need of forest patches for additional conservation-protection. Qualities for higher ranking included forest patches with & greater than 2000 ha of core-forest that was more than 250 m from an edge, forest patches within high priority areas for reforestation, and forest patches with less propensity for flooding. Digital data are provided for: 1. Boundary of the Mississippi Alluvial Valley study area. 2. Forest cover (circa 2015) used to for determination of forest area in need of conservation protection. 3. The conservation estate (circa 2019) that had conservation protection by virtue of ownership, easement, or servitude. 4....
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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