She became his full collaborator in butterfly research, although she did not have a Ph.D.[4] Following the war in 1945, he began work as the assistant director of zoology at the Royal Ontario Museum.
[3] He wrote four books, a monograph, and 62 papers in peer-reviewed journals, as well as numerous scientific reports and popular articles.
[3] They founded the first Insect Migration Association, today known as Monarch Watch, and recruited hundreds of volunteers or "citizen scientists" who helped in their research by tagging butterflies and reporting findings and sightings.
[5] The Urquharts raised thousands of monarchs at their home in Scarborough, Ontario, as well as using the facilities of the University of Toronto to analyze their findings and do research.
[6][7] The Urquharts identified several distinct migration routes but were baffled why the trail seemed to disappear in Texas in the late fall, only to reappear in the spring.
On January 9, 1975, Kenneth C. Brugger and his wife Catalina Trail (then known as Cathy Aguado) finally located the first known wintering refuge for the butterflies on a mountaintop in Michoacán, Mexico, more than 4,000 kilometers from the starting point of their migration.