Background
Williamson was born in Bury Lancashire.
Williamson was born in Bury Lancashire.
From 1948-1957 he was Director of the Fair Isle Bird Observatory. Subsequently he became a Senior Research Officer with the British Trust for Ornithology and from 1958-1963 he was editor of the journal Bird Migration. From 1959-1963 he served on the British Birds Rarities Committee.
On 2 February 1959 Williamson was elected a Fellow of the Royal Society of Edinburgh.