DOI: 10.5061/dryad.cc2fqz6hk
title: In the clear: Weather drives the northward movement of American Tree Sparrows (Spizelloides arborea) as spring progresses

description: The American Tree Sparrow (Spizelloides arborea) is a sub-Arctic breeding
 species that spends the nonbreeding season in temperate regions of North
 America, and is a high-priority candidate for conservation status
 assessment. To provide new information about their movement ecology and
 migratory connectivity, we used automated radiotelemetry to track their
 movements and stable-isotope analysis of feathers to infer breeding or
 natal origin. The work is published in the Journal of Field Ornithology.
 In this repository, we include several datasets that support the work and
 an R script showing the geographical assignment procedure.
description: # In the clear: Weather drives the northward movement of American Tree
 Sparrows (*Spizelloides arborea*) as spring progresses Dataset DOI:
 [10.5061/dryad.cc2fqz6hk](10.5061/dryad.cc2fqz6hk) ## Description of the
 data and file structure We used Motus automated radiotelemetry to track
 the movements of American Tree Sparrows and stable-isotope analysis of
 feathers to infer their breeding or natal origin. This repository contains
 the data used to support the publication in the Journal of Field
 Ornithology and an R script to show the geographical assignment procedure.
 ### Files and variables #### File: ATSPassigment.R **Description:** R
 script code to assign geographical origin to American Tree Sparrows based
 on their feather deuterium value #### File: ATSPdeparture.rds
 **Description:** departure time from capture locations; *.rds can be read
 by readRDS in R ##### Variables * motusTagID: unique identifier for the
 Motus radiotransmitter * year: year of the study (YYYY) * Location:
 capture location (OLD CUT, GUELPH = Guelph Lake Nature Centre) *
 capture.yday: capture day of year * Age: age class (AHY =
 after-hatch-year, HY = hatch-year) * ts_depart: datetime of departure
 (YYYY-MM-DD hh:mm:ss), set in UTC to be used in UTC system-time-zone *
 yday_closest_sunset: last day of the year at the capture location during a
 diurnal period (i.e., day of departure). For example, a bird leaving at 1
 am would be associated with the previous day - depart_sunset - hours since
 the most recent sunset #### File: ATSPisotope.csv **Description:** feather
 deuterium values ##### Variables * BandNumber: USGS leg band number *
 motusTagID: unique identifier for the Motus radiotransmitter * year: year
 of the study (YYYY) * Location: capture location (OLD CUT, GUELPH = Guelph
 Lake Nature Centre) * Age: age class (AHY = after-hatch-year, HY =
 hatch-year) * isotope: stable hydrogen isotope ratio of feather tip in
 parts per thousand #### File: ATSPrecurrent.rds **Description:** daily
 event data with time-varying weather variables; *.rds can be read by
 readRDS in R ##### Variables * motusTagID: unique identifier for the Motus
 radiotransmitter * year: year of the study (YYYY) * capture.yday: capture
 day of year * Age: age class (AHY = after-hatch-year, HY = hatch-year) *
 yday: day of year of the relocation event * tstart: number of days since
 capture - 1 * tstop: number of days since capture * move: presence of a
 nocturnal relocation event (0 = no, 1 = yes) * temp: near surface air
 temperature (degrees Celsius); calculate from NCEP/NCAR variable
 'air.sig995' * pres: atmospheric pressure (kPa); calculated from
 NCEP/NCAR variable 'pres.sfc' * tcdc: total cloud cover for 6 h
 beginning at reference time (%); NCEP/NCAR variable 'tcdc.eatm'
 * prate.sfc: precipitable water at surface (rain or snow in kg/m^2);
 NCEP/NCAR variable 'pr_wtr.eatm' * uwind1000: u component of
 wind at 1000 mb (m/s); NCEP/NCAR variable 'uwnd' * vwind1000: v
 component of wind at 1000 mb (m/s); NCEP/NCAR variable 'vwnd' *
 snow_grnd: daily snow on ground (cm) #### File: ATSPrelocations.rds
 **Description:** timing of nocturnal relocation events; *.rds can be read
 by readRDS in R ##### Variables * motusTagID: unique identifier for the
 Motus radiotransmitter * year: year of the study (YYYY) * Location:
 capture location (OLD CUT, GUELPH = Guelph Lake Nature Centre) *
 capture.yday: capture day of year * Age: age class (AHY =
 after-hatch-year, HY = hatch-year) * yday_sunset: day of year associated
 with the nocturnal relocation * ts: datetime of passage timing (YYYY-MM-DD
 hh:mm:ss), set in UTC to be used in UTC system-time-zone) *
 recvDeployName: Motus receiver name * recvDeployLat: Motus receiver
 latitude (decimal degrees) * recvDeployLon: Motus receiver longitude
 (decimal degrees) ## Code/software All data processing, statistical
 analysis, and figure generation were done in R version 4.4.1 (2024-06-14
 ucrt). ATSPassignment.R shows the geographical assignment procedure. ##
 Access information Citation for the publicly accessible weather data: *
 Kalnay, E., M. Kanamitsu, R. Kistler, W. Collins, D. Deaven, L. Gandin, M.
 Iredell, S. Saha, G. White, J. Woollen, Y. Zhu, A. Leetmaa, M. Chelliah,
 W. Ebisuzaki, W. Higgins, J. Janowiak, K. C. Mo, C. Ropelewski, J. Wang,
 R. Jenne et al. 1996. The NCEP/NCAR 40-year reanalysis project. Bulletin
 of the American Meteorological Society 77:437-470. Citation for the
 publicly accessible Motus data: * Hannah, K., S. Mackenzie, R. Wood, J.
 Costa, and M. Cadman. 2020a. American Tree Sparrows - Ontario (Project
 231). Data accessed from Motus Wildlife Tracking System, Birds Canada.
 [https://motus.org/](https://motus.org/)