About ISAN

Our Mission

We work to promote behavior change that reduces the human-caused spread of invasive species.

Our Staff

Sara Ricklefs

Sara Ricklefs

Executive Director

Sara’s passion for invasive ecology began during graduate school where she studied juvenile dispersal of an invasive species of crayfish on the Pecos River. After graduation, she monitored the spread and sought funding for woody invasive mitigation to improve wildlife habitat in eastern New Mexico. Sara’s aim at ISAN is to improve invasive species management, outreach, and prevention with great focus on impacts from continued climatic change. On any given weekend, you can expect to catch up with her on a kayak, at a trailhead, or in a local bookstore.
Leah Elwell

Leah Elwell

Deputy Director

Prior to taking the helm at ISAN, Leah led our programs for almost a decade. She often cannot believe that she has spent the majority of her life working on invasive species issues.  Now more than ever, Leah remains focused on bring partners together to tackle the complexities of invasive species. When not dreaming up new ways to change the world for good, Leah is digging in the dirt, hiking the hills and having fun with her family.
Jennifer Riddle

Jennifer Riddle

Programs Manager

Growing up somewhere between the swamps and the gulf coast of Florida, exploring her home waters of the Hillsborough river system Jennifer has always been curious about life on the water. It was through her college work as an ecology research assistant that she gained a deeper understanding of aquatic ecosystems and the world of creatures that depend on their health. Since moving to Montana, Jennifer’s work has focused on public engagement on issues promoting healthy waterways. Outside of her ISAN responsibilities, you can likely find Jennifer floating rivers with her dog, Frank, or looking for snakes and berries on trails!

Our Founding

Robert Wiltshire founded the Invasive Species Action Network in 2008 realizing that the current efforts to address the aquatic invasive species problem fell short. With a well-rounded career conducting wild trout studies for the state of Montana for over 15 years, small-business entrepreneur in recreation and hobbies, and conservation non-profit manager for more than a decade, Bob navigated his role as executive director with ease. He played key roles in the management of invasive species over the years including serving on the Montana’s Whirling Disease Task Force, co-authoring the Western States New Zealand Mud Snail Management plan and serving on the National Invasive Species Advisory Committee to the White House. In 2019, Bob retired from ISAN to pursue his personal goals and hobbies.

Our Board

We consider ourselves lucky to have board members who are active in our local community and interested in helping us to get the word out about preventing the spread of invasive species.


  • Brant Oswald, Chair
  • Todd Wester,  Secretary
  • Deb Earl, Director
  • Wendy Weaver, Director

Volunteering Opportunities

Interested in getting involved? Volunteer opportunities change depending on the location and time of year.

 ISAN attends a variety of events, depending on the time of year. No specific skills are required, but an interest in the subject of the event you attend is helpful.

If you’re interested in any of our programs, feel free to reach out to learn how you can help! 

2 + 14 =

Are you ready to help prevent the spread of invasive species?

Take the Pledge!

Invasive Species Prevention Pledge

7 + 8 =

Invasive species pose one of the greatest threats to biodiversity today, but preventing their spread is easy. This pledge provides the on-ramp for people everywhere to be part of the solution in preventing the spread of invasive species.

- Leah Elwell, ISAN Deputy Director