He attended Palmerston North Boys' High School and went on to study for a BSc at Victoria University in 1958.
[1] Despite only receiving a C pass in Zoology, he was accepted into the graduate programme where he completed an MSc thesis on the biology of the redfin bully.
[1] At that time, the main laboratories of the Marine Department were housed on the ground floor of the old Wellington City morgue – which McDowall described as an "unhappy and "exceedingly primitive' place with inadequate power and heating.
[2] He left New Zealand on a small cargo ship with an "entry permit to the United States and Harvard, a good scholarship, an extensive fish collection and a wife of 10 days".
His last book, Ikawai: freshwater fishes in Māori culture and economy, was published in October 2011 following his death on 20 February 2011.