Karen Oberhauser

Karen Suzanne Oberhauser (born c. 1956) is an American conservation biologist with a specific interest in monarch butterflies.

She studied biology at Harvard College and received a PhD from the University of Minnesota. Oberhauser is a professor in the Fisheries, Wildlife and Conservation Biology department at the University of Minnesota.

Oberhauser married Don Alstad in 1985; the couple had two daughters. Don died in April 2014 at the age of 67.

In 2013, she was named a Champion of Change for Citizen Science by the White House. Oberhauser has been director for the Monarchs in the Classroom Program, president of the Monarch Butterfly Sanctuary Foundation and director of the Monarch Larva Monitoring Project.

Besides publications in scholarly journals, she has also been co-editor for two books published by Cornell Press:

• The Monarch Butterfly: Biology and Conservation ISBN 978-0-8014-4188-2
• Monarchs in a Changing World: Biology and Conservation of an Iconic Butterfly ISBN 978-0-8014-5315-1

In 2014, Oberhauser and a colleague published a scientific article examining how usage of Monsanto's Roundup herbicide on farmland in North America contributes to the decline of milkweeds, important food sources for the butterflies. They found that the size of populations of milkweed were smaller in areas of increased Roundup use, suggesting that the loss of this food source may contribute to the decline of Monarchs. The milkweed limitation hypothesis as this has become known, has been tested by other groups of scientists finding conflicting results. Thus, the actual contribution of Roundup use and loss of populations of milkweed to the decline of Monarch butterflies is still unclear.