 In 1963 he migrated to Australia where he joined the Bureau of Mineral Resources in Canberra.Marchant was born in Weston-under-Lizard, a village in the English county of Shropshire.In Australia, Marchant was immediately involved in organised ornithology through the Royal Australasian Ornithologists Union (RAOU) where he was a strong force for what he perceived to be necessary reform.