Decline of the Bewick’s Swans<i> Cygnus columbianus bewickii</i> population wintering in Northeast/Northwest Europe

The R code associated with a population model used to project Bewick's Swan population size between 2010 and 2026. The code contains all of the requisite data for all parameters, and requires no additional files. This work was carried out as part of the forthcoming paper, "Decline of the Bewick’s Swans <i>Cygnus columbianus bewickii</i> population wintering in Northeast/Northwest Europe", to be published in <i>Wildfowl</i>. In addition to the annotations provided in the model code, a description of the model is provided in the methods section of the forthcoming paper.