DOI: 10.5061/dryad.18931zctp
title: Data from: Habitat loss and thermal tolerances influence the sensitivity of resident bird populations to winter weather at regional scales

description: 1. Climate change and habitat loss pose the greatest contemporary threats
 to biodiversity, but their impacts on populations largely vary across
 species. These differential responses could be caused by complex
 interactions between landscape and climate change and species-specific
 sensitivities. 2. Understanding the factors that determine which species
 are most vulnerable to the synergistic effects of climate change and
 habitat loss is a high conservation priority. Here, we ask (a) whether and
 to what extent land cover moderates the impacts of winter weather on
 population dynamics of wintering birds, and (b) what role species’
 physiology might play in modifying their responses to changing weather
 conditions. 3. To address these questions, we used thousands of
 observations collected by citizen scientists participating in Project
 FeederWatch to build dynamic occupancy models for 14 species of wintering
 birds. 4. Populations of wintering birds were more dynamic, having higher
 rates of local extinction and colonization, in more forested landscapes
 during extreme cold – presumably enabling them to better track resources.
 However, urban areas appeared to provide refuge for some species, as
 demonstrated by increased local colonization during the harshest winter
 weather. Lastly, we found that species-specific differences in thermal
 tolerances strongly influenced occupancy dynamics such that species that
 are less cold-tolerant were more likely to go locally extinct at colder
 sites and during colder periods throughout winter. 5. Together, our
 results suggest species that are less cold-tolerant and populations
 occupying less forested landscapes are most vulnerable to extreme winter
 weather. 11-Jun-2020
description: Project FeederWatch (PFW) data have undergone the automated
 filter and validation checks established by PFW researchers and were
 analyzed in consultation with members of the Cornell Lab of Ornithology
 (CLO). Requests for data beyond the scope of the linked publication should
 be submitted directly to PFW through the CLO. Re-use of PFW data should
 acknowledge the thousands of participants who have made FeederWatch
 possible, as well as to Birds Canada and the Cornell Lab of Ornithology
 for developing and managing the program. Additional details can be found
 at the Project FeederWatch website: https://feederwatch.org/explore/raw-dataset-requests/ Maximum cold-induced metabolic rates (Msum) were obtained from the literature and standardized by body mass (in grams). Please see the linked paper for more details. In cases where there were multiple Msum values per species, we selected the value closest to the years of study (2009, 2012 & 2015). Slope values for local extinction/colonization and detection probabilities versus seasonal temperature fluctuations were obtained through dynamic multi-season occupancy models.  
description: <strong>PFW
 Data</strong> Column
 variables:  1) ID_DATE -- Combination internal user ID,
 Location ID, FeederWatch year and Pseudojulian date. Note: Some users have
 multiple locations associated with their unique user ID.
 2)  Year -- Numeric year in which the observation was
 made 3) Month -- Numeric month in which the observation
 was made 4) Day -- Numeric day in which the observation
 was made 5) LATITUDE -- decimal latitude of the
 centroid of the PFW observation location 6) LONGITUDE
 -- decimal longitude of the centroid of the PFW observation
 location 7) NHalfDays -- number of half-day periods
 over the 2-day count in which observations were made (1, 2, 3, or 4
 half-days) 8) EFFORT_HRS_ATLEAST -- Low end of the
 recorded effort range of number of hours spent observing. Note: some
 participants record a range of effort while others record a precise
 number.  9) StatProv -- State/province code of the PFW
 site as provided by the user 10) BirdSpp -- code for
 the species seen 11) NSeen -- Maximum count of the
 species seen at any one time during the 2-day count period
   <strong>Msum
 Data</strong> Column
 variables: 1) sp -- species identifier codes from
 Project Feederwatch 2) Msum -- mass-corrected maximum
 cold-induced metabolic rate 3) slp_col -- colonization
 slope (Beta) coefficient quantifying the relation between local
 colonization and minimum temperature 4) slp_ext --
 extinction slope (Beta) coefficient quantifying the rlationship between
 local extinction and minimum teperature 5) slp_det --
 detection slope (Beta) coefficient quantifying the relationship between
 detection probability and minimum temperature 6) year
 -- numeric year corresponding to each Project FeederWatch season