This Halpin_etal_2021_readme.txt file was generated on 2021-08-03 by Luke Halpin GENERAL INFORMATION 1. Title of Dataset: Double-tagging scores of seabirds reveals that light-level geolocator accuracy is limited by species idiosyncrasies and equatorial solar profiles. 2. Author Information Halpin, L.R., Ross, J.D., Ramos, R., Mott, R., Carlile, N., Golding, N., Reyes-González, J.M., Militão, T., De Felipe, F., Zajková, Z., Cruz-Flores, M., Saldanha, S., Morera-Pujol, V., Navarro-Herrero, L., Zango, L., González-Solís, J. and Clarke, R.H. (2021), Double-tagging scores of seabirds reveals that light-level geolocator accuracy is limited by species idiosyncrasies and equatorial solar profiles. Methods Ecol Evol. https://doi.org/10.1111/2041-210X.13698 3. Geographic location of data collection: Cala Morell (Menorca), Spain, Mediterranean Islas Columbretes, Spain, Mediterranean Isla de Cabrera, Spain, Mediterranean Isla de las Palomas, Spain, East Atlantic Islote de Montaña Clara, Spain, East Atlantic Timanfaya (Lanzarote), Spain, East Atlantic Veneguera (Gran Canaria), Spain, East Atlantic Ilhéu Raso, Cabo Verde, East Atlantic Ilha Boa Vista, Cabo Verde, East Atlantic Ilhéu de Curral Velho, Cabo Verde, East Atlantic Phillip Island (Norfolk Island), Australia, South Pacific 4. Information about funding sources that supported the collection of the data: LRH received funding support with an Endeavour Postgraduate Leadership Award by the Australian Government. Fieldwork was supported with awards to LRH by the Holsworth Wildlife Research Endowment – Equity Trustees Charitable Foundation & the Ecological Society of Australia and the Birdlife Australia Stuart Leslie Bird Research Award. Fieldwork was also supported by New South Wales Office of Environment & Heritage and Parks Australia. RR acknowledges funding with a postdoctoral Ramón y Cajal contract of the Spanish Ministry of Economy, Industry and Competitiveness (RYC-2017-22055), and ZZ with a doctoral grant of the University of Barcelona (APIF-2012). Pacific tracking data were collected under Monash University Animal Ethics Permit BSCI/2017/42 and Parks Australia wildlife research approvals. Tracking data from the Atlantic and Mediterranean were gathered with valuable help from many students and volunteers to whom we are enormously grateful. These data were collected under the following permits: Cabildo de Lanzarote num. I-15-16-T, Cabildo Gran Canaria num. 1169, Excmo. Cabildo de Lanzarote 2107, Excmo. Cabildo de Lanzarote num. 1948, Excmo. Cabildo de Lanzarote num. 2018/2290, Generalitat Valenciana num. 249-18 SGENP, Gobierno de Canarias num. 2011/0795, Gobierno de Canarias num. 2015/1170 & 2016/9887, Gobierno de Canarias num. 2018/6432, Govern Balear num. ANE-02/2017, Govern Balear num. ANE-05/2016, Govern Balear num. CEP-24/2015, Govern Balear num. CEP-30/2016, Govern Balear num. CEP-31/2014, Parque Nacional num. 160/15, Parque Nacional num. RES-AUT I03/2015, Región de Murcia num. AUF20140056. SHARING/ACCESS INFORMATION 1. Licenses/restrictions placed on the data: This work is licensed under a CC0 1.0 Universal (CC0 1.0) Public Domain Dedication license. 2. Links to publications that cite or use the data: https://doi.org/10.1111/2041-210X.13698 3. Was data derived from another source? No 6. Recommended citation for this dataset: Halpin, L.R., Ross, J.D., Ramos, R., Mott, R., Carlile, N., Golding, N., Reyes-González, J.M., Militão, T., De Felipe, F., Zajková, Z., Cruz-Flores, M., Saldanha, S., Morera-Pujol, V., Navarro-Herrero, L., Zango, L., González-Solís, J. and Clarke, R.H. (2021), Double-tagging scores of seabirds reveals that light-level geolocator accuracy is limited by species idiosyncrasies and equatorial solar profiles. Methods Ecol Evol. https://doi.org/10.1111/2041-210X.13698 DATA & FILE OVERVIEW 1. File List: Output files from light-level geolocation analysis depending on model parameterisation: a. flightr_parameter_set_1_oFALSE_maskFALSE_knownTRUE.csv b. flightr_parameter_set_2_oFALSE_maskTRUE_knownTRUE.csv c. flightr_parameter_set_3_oTRUE_maskFALSE_knownTRUE.csv d. flightr_parameter_set_4_oTRUE_maskTRUE_knownTRUE.csv Columns 1-18 in files a-d are results produced by the FLightR package (Rakhimberdiev et al., 2017). e. probGLS_parameter_set_1_SST_FALSE_mask_FALSE.csv f. probGLS_parameter_set_2_SST_FALSE_mask_TRUE.csv g. probGLS_parameter_set_3_SST_TRUE_mask_TRUE.csv Columns 1-39, 44-47 and 54-56 in files e-g are results produced by the probGLS package (Merkel et al., 2016). In generalized additive models (GAMs) we used the results outputs from the models that did not include land masks (e.g only files a and e) In files a-d, the metrics used to complete the analysis are: medianLat: the median of the posterior probability distribution for geolocation latitudes. medianLon: the median of the posterior probability distribution for geolocation longitudes. gps.lat.mean: the geographic mean of all latitudinal GPS positions recorded within ±30 minutes of the given geolocation twilight. gps.lon.mean: the geographic mean of all longitudinal GPS positions recorded within ±30 minutes of the given geolocation twilight. id: the id of a bird (containing the island which it is from, the bird's id and the year in which it was tracked, i.e. island_id_year) midpoint.median.distance: Great-circle distance (kilometres) between the geographic mean of all GPS fixes that occurred within ± 30 min, respectively, of a given pair of twilights (i.e., sunset-sunrise or vice versa) and the geolocator-estimated solar noon/midnight position for that same period. Displacement: Great-circle distance (kilometres) between successive twilight locations (from GPS) for individuals. species_com: Species common name. days_since_equinox: number of days since the equinox. doy: day of the year (e.g. 1-365) rel_error: relative accuracy (see Discussion in manuscript). gls_type: model of geolocator. local_timezone: Local timezone calculated from GPS coordinates. local_time: Local time calculated from GPS coordinates. DayNight: whether a position occurred during the day or at night. tFirst: The first geolocation twilight. tSecond: The second geolocation twilight. expected_intertwilight_period: as the expected duration of day or night calculated from day of year and GPS latitude. intertwilight_period: Observed inter-twilight period calculated from geolocator twilights (i.e., duration of time in hours between twilights). Metadata for tracking file information: Supplementary Tracking Metadata.csv Code used to generate geolocations and analyse data: Analysis_Code.R Zip file containing light-level data: light_data.zip DATA-SPECIFIC INFORMATION: Analysis_Code.R contains the code used to generate and analyse geolocations. Each of the output files contain the GPS locations (gps.lon.midpoint.mean & gps.lat.midpoint.mean) used to calculate the distance from the geolocation (midpoint.median.distance) along with the longitude (lon) and latitude (lat) of each geolocation. Methods concerning these distance calculations are discussed in the main manuscript. Metadata column headings have the following meanings: species_com species common name species_sci species scientific name flight_group type of flight used to calculate flight speeds in probGLS bird_id identity of each bird (not used in analyses) id identity for each individual bird (used in analyses) TAGS_file filename of the TAGS file TWL_file filename of the twilights file gls_id filename of the raw light data gls_temp filename of the raw geolocator temperature file gls_wet_dry filename of the wet/dry data file gls_temp_start minimum observed date range in the temperature file gls_temp_end maximum observed date range in the temperature file battery_OK_recovery denotes whether the battery was functioning upon recovery of the geolocator calibration_type denotes whether the stationary calibration data exists on the same light data file as in "gls_id" or a separate file gls_calibration_id filename for the calibration data if not included in "gls_id" file gps_id id of the gps tag stage breeding stage of the individual bird PERIOD 1 START: start date of the tracking period in which an individual carried both geolocator and GPS PERIOD 1 END: end date of the tracking period in which an individual carried both geolocator and GPS colony_name locality name of the colony country country name colony_location island name of the colony local_timezone local time zone colony_lat latitude of the colony colony_lon longitude of the colony gps_type type of gps tracker gps_attach gps attachment method gps_tz gps timezone gps_sched gps sample rate gls_type geolocator make and model gls_attach geolocator attachment method gls_prog manufacturer-specific geolocator program type gls_cal_lat latitude of the geolocator calibration gls_cal_lon longitude of the geolocator calibration gls_cal_start geolocator calibration start date gls_cal_end geolocator calibration end date calib_length length of calibration in days dbl_tag_start start date on which an individual carried both geolocator and gps dbl_tag_end end date on which an individual carried both geolocator and gps algorithm denotes whether data from an individual was used in both FLightR and probGLS, or one or the other. deploy_duration duration of double tagging deployment (days) flight_speed flight speed used to inform probGLS analysis for when loggers were dry light_data.zip contains, for each colony, a folder with the raw light-data ("raw"), the annotated twilights file ("twilights) and the resulting TAGS file ("tags") for each individual. The folder "external_calibration_files" contains, if applicable for a given individual (ie., see "gls_calibration_id" in metadata), the stationary calibration data. REFERENCES Merkel, B., Phillips, R. A., Descamps, S., Yoccoz, N. G., & Moe, B. (2016). A probabilistic algorithm to process geolocation data. Movement Ecology. doi:10.1186/s40462-016-0091-8 Rakhimberdiev, E., Saveliev, A., Piersma, T., & Karagicheva, J. (2017). FLightR: an R package for reconstructing animal paths from solar geolocation loggers. Methods in Ecology and Evolution, 8(11), 1482–1487. doi:10.1111/2041-210X.12765