DOI: 10.5061/dryad.vt4b8gtv9
title: Data and code to explore annual cycle schedule adjustments in a long distance migrant

description: Matching the timing of annual cycle events with the required resources can
 have crucial consequences for individual fitness. But as the annual cycle
 is comprised of sequential events, a delay at any point may be carried
 over to the subsequent stage (or more, in a domino effect) and negatively
 influence individual performance. To investigate how migratory animals
 navigate their annual schedule, and where and when it may be adjusted, we
 used full annual cycle data of 38 Icelandic whimbrels Numenius phaeopus
 islandicus tracked over 7 years –  a subspecies that typically
 performs long-distance migrations to West Africa. We found that
 individuals apparently used the wintering sites to compensate for delays
 that mostly arose due to previous successful breeding, and a domino effect
 was observed from spring departure to laying date, with the potential to
 affect breeding output. However, the total time saved during all
 stationary periods is apparently enough to avoid interannual effects
 between breeding seasons. These findings highlight the importance of
 preserving good quality non-breeding sites in which individuals may adjust
 annual schedules and avoid potentially adverse effects of arriving late at
 the breeding grounds.
description: # Data and code to explore annual cycle schedule adjustments in a long
 distance migrant
 [https://doi.org/10.5061/dryad.vt4b8gtv9](https://doi.org/10.5061/dryad.vt4b8gtv9) ## Description of the data and file structure This study investigates how migratory animals navigate their annual schedule, and where and when adjust it, using the Icelandic whimbrel (Numenius phaeopus islandicus) as a model. Individuals apparently compensated for delays at the wintering sites, which mostly arose due to previous successful breeding, and a domino effect was observed from spring departure to laying date, with the potential to affect breeding output. We appreciate that anyone interested in using these data contacts the authors. ### Files and variables Following variables explanation, the corresponding R script is mentioned, with indication R packages required, and the versions used, to analyse the dataset. All analysis were conducted in R version 4.0.3. ### dataSEM Variable explanation: * fledge_1 - fledging success in the year of end (t+1); * lay_date_1 - laying day in the year at end of tracking (t+1); * arr_iceland - spring arrival (day of the year). R script: MS_code_piecewiseSEM packages: piecewiseSEM, version 2.1.2 lme4, version 1.1-26 dplyr, version 1.0.3 performance, version 0.7.1 \--- ### dataStationary Variable explanation: * combo_f - individual identifier; * year_0 - year of start of tracking (t); * year_1 - year of end of tracking (t+1); * fledge_0 - fledging success in the year of start (t); * sex - sex of the individual; * dep_iceland - autumn departure (day of the year); * arr_winter - autumn arrival (day of the year); * dep_winter - spring departure (day of the year); * arr_iceland - spring arrival (day of the year); * strategy_spr - spring migratory strategy; * stopover_duration - duration of stopover (in days); * spr_duration - duration of spring migratory movement (i.e. difference between departure and arrival date; in days); * winter_distance - distance between breeding and wintering site (in km); * lay_date_1 - laying day in the year at end of tracking (t+1); * nest_id - nest identifier. R script: MS_code_stationaryperiods packages: lme4, version 1.1-26 lmerTest, version 3.1-3 dplyr, version 1.0.3 performance, version 0.7.1 \--- ### dataFledging Variable explanation: * combo_f - individual identifier; * year_0 - year of start of tracking (t); * fledge_0 - fledging success in the year of start (t); * sex - sex of the individual; * dep_iceland - autumn departure (day of the year); * dep_winter - spring departure (day of the year); * arr_iceland - spring arrival (day of the year); * winter duration - period from autumn arrival to spring departure (in days); * stopover_duration - duration of stopover (in days); * arrival_lay_gap - period from spring arrival to egg laying; * strategy_spr - spring migratory strategy; * winter_distance - distance between breeding and wintering site (in km); * spr_duration - duration of spring migratory movement (i.e. difference between departure and arrival date; in days); * geo - geolocator code. R script: MS_code_fledging packages: lme4, version 1.1-26 lmerTest, version 3.1-3 performance, version 0.7.1 \--- ### other datasets: **nest_locations**: approximate nest locations (latitude and longitude in decimal degrees). **body_mass**: body mass of whimbrels (in grams). **non_light_data**: date (DD/MM/YYYY HH:MM:SS), temperature (minimum and maximum; ºC), conductivity and wet contacts recorded by the geolocators. conductivity and wet/dry sampled every 30 s with maximum conductivity and amount of wet contacts stored every four hours (mode 1 was used; see Migrate Technology Ltd documentation for more details). ## Change Log **Feb 2025**: Files under "other datasets" were added.