# Title of Dataset: Autumn fueling behavior in passerines in relation to migratory distance and day length --- LBM data: These data were collected as a part of the standardized ringing scheme at Ottenby Bird Observatory in Ottenby, Sweden. Fueling data: The data are from an fueling experiment where juvenile birds were captured during autumn migration and given ad lib. meal worms while being exposed to either an extended or natural daylength regime for up to 10 days. Maximum 24-hour fueling rates and maximum fuel loads were calculated from the data. Lean body mass was estimated using a linear regression relating wing length to body size. ## Description of the Data and file structure LBM data: ring_number - individual identifier on metal ring that is attached to the leg of the bird species - ROHAK = European Robin (Erithacus rubecula), LOSAN = Willow Warbler (Phylloscopus trochilus), PHCOL = Common Chiffchaff (Phylloscopus collybita), ARSAN = Lesser Whitethroat (Curruca curruca), BLMES = Blue Tit (Cyanistes caeruleus) wing_length - maximum (flattened, straightened) wing length (mm) mass - weight of bird measured with digital scale (g) fat_score - on a scale of 0-9 according to a visual scale for fat classification (Pettersson & Hasselquist, 1985; Sjöberg et al., 2015) Fueling data: ring_number - individual identifier on metal ring that is attached to the leg of the bird species - ROHAK = European Robin (Erithacus rubecula), LOSAN = Willow Warbler (Phylloscopus trochilus), PHCOL = Common Chiffchaff (Phylloscopus collybita), ARSAN = Lesser Whitethroat (Curruca curruca), BLMES = Blue Tit (Cyanistes caeruleus) cage - cage number (one individual per cage at a time) treatment - extended = daylength extended to 24 hours/day using a lamp, control = natural daylength using a lamp switched on at sunrise and switched off at sunset (kept constant from the first day of the trial), 1-4 = trial number daylength - number of hours when lamp is switched on per day capture_date - the date when the individual was captured at the ringing station capture_time - the time when the individual was captured at the ringing station ringer_ID - code for the identity of the observer who initially ringed the bird age - 10 = first calendar year wing_length - maximum (flattened, straightened) wing length (mm) capture_mass - mass of bird when it was initally captured (g) molt - classification for molt status on a scale of 1-6 max_mass - maximum mass recorded during fueling experiment (g) LBM - estimate of lean body mass (g) start_date - first day of fueling experiment with ad lib. food end_date - last day of fueling experiment with ad lib. food max_delta_mass - greatest single day mass change (g) day_max_delta_mass - day of experiment when bird had greatest mass change, 1 = first day, 2= second day, etc. exp_length - length of fueling experiment (days) settling_time - number of days in captivity before start of experiment, 1 = first day in captivity, 2 = second day in captivity, etc. max_FDR - maximum fuel deposition rate as a percent of lean body mass max_FL - maximum fuel load as a percent of lean body mass ## Sharing/access Information LBM data: The data were kindly provided by Ottenby Bird Observatory for the purpose of this project. Long-term ringing data can be requested from the Swedish Ringing Centre (Ringmärkningscentralen) or from Ottenby Bird Observatory. Was data derived from another source? Fueling data: LBM (lean body mass) was estimated using linear regression equations relating wing length to body size. The equations were derived from the LBM data set.