he started one of the world's first two bird ringing schemes in 1909 (they merged in the late 1930s), transferring responsibility, in 1937, to the british trust for ornithology (bto), who continue to run it. witherby was hon secretary and treasurer (1904–14), and chairman (1924–27) of the british ornithologists' club (1924–1927) and president of the council of the british ornithologists' union (bou) (1933–1938). he was a founding member and early vice-chairman of the bto, which survived through his financial generosity, not least in donating the proceeds of the sale of his extensive collection of stuffed birds to the british museum - this is now at the natural history museum, tring.