The Crown of the Continent ecoregion straddles the Continental Divide from Crowsnest Pass in Canada to Rogers Pass in northwest Montana. The region includes Glacier National Park, Waterton Lakes National Park, the Bob Marshall Wilderness complex, the Mission Mountains Tribal Wilderness, Akamina-Kishinena Provincial Park, and several state, national, and provincial forests.

The Crown is one of the most spectacular and most pristine regions of North America, and a hotspot for diatom biodiversity. We set out to survey diatom biodiversity in the Crown in 2006, with emphasis on the Waterton-Glacier International Peace Park. Including historic samples in the Montana Diatom Collection dating back to the 1970s, we have collected 529 samples from 399 localities in the region. A preliminary analysis of samples indicates the region supports well over 1,000 diatom species, many of them new to science.

In eight papers published since 2009, we have described 23 new diatom species that live in the Crown. The type localities for 21 of these species are within the Crown ecoregion. The region is rich in nordic-alpine taxa, including the rare Distrionella incognita. Ours were the first records of this taxon in North America. The region also supports large populations of the native diatom Didymosphenia geminata, which has become a concern in Glacier National Park.


  • National Park Service, Rocky Mountain Monitoring Network

    - Loren Bahls

  • Rocky Mountain Cooperative Ecosystems Study Unit (RM-CESU)

    - Loren Bahls

  • Anonymous Donor

    Glacier National Park Fund - Loren Bahls

  • National Institutes of Health

    National Center for Research Resources, Biomedical Research Infrastructure Network - Electron Microscopy Facility, Division of Biological Sciences, University of Montana, Missoula


Loren Bahls

Faculty Affiliate Environmental Studies, The University of Montana

Kalina Manoylov

Assistant Professor Georgia College and State University

E. William “Billy” Schweiger

National Park Service, Rocky Mountain Monitoring Network

Tara Carolin

National Park Service, Glacier National Park

Barb Johnston

Parks Canada

Swiftcurrent  Lake And  Valley
Image Credit: Loren Bahls
Swiftcurrent Lake and Swiftcurrent Valley, Montana
Loren  Teton Pass Outbound
Image Credit: Bob Fox
Entering the Bob Marshall Wilderness at Teton Pass in August 1983. This was the first day of a 9-day, 70-mile hike into the heart of 'The Bob' to sample diatoms from three backcountry lakes: Dean, Levale, and Trilobite.
Image Credit: Loren Bahls
Distrionella incognita, Eunotia diadema and Navicula whitefishensis, three iconic species of Glacier National Park.
Image Credit: Mark Edlund
Lliving cells of Cocconeis placentula are prostrate, attached by one valve surface.