Dr John Barclay Tait FRSE (1900–1973) was a 20th-century British hydrographist.
From 1962 to 1965 he was Deputy Director of the Marine Laboratory in Aberdeen linked to the Fishery Board for Scotland.
He studied Science at Heriot-Watt College graduating BSc in 1922 and followed this with a doctorate (PhD).
In 1928 he was appointed a Junior Naturalist to the Fishery Board of Scotland alongside Sydney Guy Gibbons.
His proposers were Alexander Bowman, Alan Grant Ogilvie, James Ritchie and Sir D'Arcy Wentworth Thompson.