Data and R-script to analyse timing of northward migration of Sanderlings (Calidris alba) through Europe.

The data file contains data of observations of individual Sanderlings (Calidris alba) from specific wintering areas observed during northward migration 
in Iceland. Each individual is indicated with a unique number in column “Individual”. The column “Winter_Area” indicates the winter location of each 
individual in sectors of 5 degrees latitude (as depicted in Fig. 1 in the paper), with 7 indicating Scotland, 8 England, 9 France, 10 North Iberia, 
11 Portugal, 13 Canary Islands, 15 Mauritania, 18 Ghana and 23 Namibia. “ Winter_MeanLat” indicates the mean latitude in decimal degrees of each 
individual. “Date_DOY” indicates the day of year on which each observation on Iceland was made. “Year” indicates the year during which an observation 
was made, “lat” is the latitude and “lon” the longitude of each observation in decimal degrees. “Sex” indicates the sex, based on molecular methods of 
an individual where 0=unknown, 1=female, 2=male. “Age”is the age of an individual, where 50=juvenile (i.e. less than 1 year old), 99=adult (i.e more 
than 1 year old) and 0 indicates that the age was unknown. Further details can be found in the methods section in the paper.

The R-script uses this dataset to analyse the variation in timing of migration through Iceland for individual Sanderlings from different non-breeding areas. Comments and explanations can also be found in the R-script and in the methods section of the manuscript.