With Burrell's interest in wild animals and his desire to preserve our natural world, he went on to receive a Bachelor of Science degree in Wildlife Biology from Colorado State University and a Master of Science degree in Wildlife Science from the University of Washington. He subsequently worked as a research biologist for the U.S. Fish and Wildlife Service, the Washington Department of Game and the Manomet Bird Observatory in Massachusetts.

In 1983, Burrell stopped working as a biologist and began his career as a wildlife and nature photographer. Burrell felt that his knowledge of and love for wild animals and his skill as a photographer would be the best way to show people the beauty and honesty of wild animals and would, therefore, accomplish more toward the preservation of the natural world.

Burrell has three times won awards in the Wildlife Photographer of the Year competition, which is sponsored by the BBC. His photographs have appeared in natural history magazines, calendars and in advertisements in Canada, Europe, Japan and the United States. Two books of his photographs, In Search of Mountain Bluebirds and When the Snow Geese Are Gone, have been published and distributed throughout the world.