The Greenland or Gyr Falcon was a favourite subject of Thorburn's. His first drawings of the bird were made from life in the aviaries at Lilford Hall, Northamptonshire in the 1880s when he was a guest of Lord Lilford.
'Perched loftily on a bleak and inaccessible promontary, a majestic Greenland falcon surveys the vastness of the arena below. The bird rests languid yet alert, contentedly digesting the mallard, recently struck down on the tarn below-whose tell tale feathers lie uneasily nearby before being blown away on the icy wind.' J. Southern, Thorburn's Landscape, London, 1981, p. 98.