John Tester was a pioneering ecologist who helped found the Department of Ecology, Evolution and Behavior in the College of Biological Sciences. He was known as an early advocate of using controlled burns to maintain prairies and forest and was early to raise the alarm about global warming. His groundbreaking book, Minnesota’s Natural Heritage: An Ecological Perspective (University of Minnesota Press 1995, 2020), was the first comprehensive book available on the Minnesota environment. It has been described as an accessible analysis of the state’s geologic history and climate. The Star Tribune review of the first edition called it “a book that should be in the home of every Minnesotan who uses the outdoors.”

Born in 1929, Tester grew up in Gibbon, a small town in south central Minnesota, where his interest in conservation and ecology began. At age 9, he joined a group of scientists who were working to restore the oak savannah in the area by helping them plant bur oaks. Tester earned his bachelor’s degree at the University of Minnesota and his master’s at Colorado State University. He completed his Ph.D. at the U of M in 1960.

After returning from Colorado in 1953, Tester worked for the Minnesota Department of Conservation (which would later become the Department of Natural Resources), where he surveyed deer, moose, ducks and pheasants. He joined the Bell Museum in 1957. 

During his time at the Bell, Tester was part of a team of researchers who first developed the use of radio equipment to track wild animals in their natural environment. They used transmitters and receivers to monitor movements and activities of many kinds of animals in Minnesota: how far deer wandered in a day, how deep gophers burrowed into the ground and where fish swam at Cedar Creek.

Tester served as a leader at Itasca Biological Station and Laboratories and in the Itasca region. He taught and conducted research at the station from 1957 until 2017. His doctoral thesis examined prairies west of the park, where he studied the effects of burning, grazing and mowing as management tools.

In 2006, when CBS initiated plans to renovate the Itasca campus, Tester led the effort to restore the director’s cabin, built in 1911 from local tamarack logs. It was the only log building that remained at the site.

Tester died in November 2019. A second edition of Minnesota’s Natural Heritage was published in 2020 to mark the book’s 25th anniversary.