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Research and Reports

Discover more about programs and studies conducted on the Reserve and in the region.



Freese Scale Introduction
Full APR Background on the Freese Scale
Freese Scale in Ecological Restoration
Current Rankings by Management Unit

To help guide our actions over time, we have developed the Freese Scale for Grassland Biodiversity, which evaluates the Reserve based on ten ecological conditions that have been most affected by human activities on lands in the APR region. The seven-point scale tracks the effects of different management decisions on ecosystem processes, such as grazing patterns, hydrology and fire. In addition to creating a common language between APR and our science partners, the Freese Scale provides our managers with a tool to measure our progress as we transition lands from a primary focus on agricultural production to a focus on biodiversity.


Bison Versus Beef 
Authored by Michel Kohl.

Bison Versus Cattle: Are They Ecologically Synonymous?
Authored by Michel T. Kohl , Paul R. Krausman , Kyran Kunkel , and David M. Williams.

Proceedings of the IVth International Wildlife Management Congress
Edited by James W. Cain III and Jason P. Marshal.

The Ecological Future of the North American Bison: Conceiving Long-Term, Large-Scale Conservation of Wildlife.
Authored by Eric W. Sanderson, Kent H. Redford, Bill Weber, Keith Aune, Dick Baldes, Joel Berger, Dave Carter, Charles Curtin, James Derr, Steve Dobrott, Eva Fearn, Craig Fleener, Steve Forrest, Craig Gerlach, C. Cormack Gates, John E. Gross, Peter Gogan, Shaun Grassel, Jodi A. Hilty, Marv Jensen, Kyran Kunkel,  Duane Lammers, Rurik List, Karen Minkowski, Tom Olson, Chris Pague, Paul B. Robertson, and Bob Stephenson.

Plant community responses to bison reintroduction on the Northern Great Plains, United States: a test of the keystone species concept
Authored by Nicholas A. McMillian, Kyran E. Kunkel, Donald L. Hagan, and David S. Jachowski.

Nic McMillan, a graduate researcher from Clemson University, was interviewed when finishing up his second summer of data collection on American Prairie Reserve. Based out of the Enrico Education & Science Center, Nic has been studying the impacts of bison grazing on prairie plant communities. He's also comparing his findings to data collected on nearby lands grazed by cattle and also in places where cows have been removed for many years. Learn more about his work and how it can apply to bison conservation across the country.




APR Bison Report (2016–2017)
APR Bison Report (2015)
APR Bison Report (2014)

We are pleased to provide you with the annual bison reports from American Prairie Reserve. The APR bison population, reintroduced in 2005 after a one hundred and forty year absence from this area of the Glaciated Plains, is healthy and growing steadily. It is an exciting challenge to continue to provide an expanding habitat base for this increasing bison population. Due to the eventual herd size, lack of cattle genes and overall treatment as a conservation herd for the public’s enjoyment, this herd is emerging as one of the most important bison populations in North America.



Climate Change Report (2016)

Climate change will be a major driver of land management decisions in the Great Plains of North America. This is a function of: (1) how to manage land to mitigate greenhouse gas (GHG) emissions and (2) how to adapt to the effects that a changing climate will have on agriculture and biodiversity. The effects of a changing climate (warmer and drier) in the Great Plains is already emerging and is expected to intensify under most climate change scenarios. American Prairie Reserve will continue to rapidly increase the acres of grasslands restored and conserved through its various approaches to land management. With each acre added, the Reserve will restore and conserve more of the region’s biodiversity, increase the ecosystem’s capacity to adapt to climate change, and ensure that more carbon is permanently sequestered in the soils of the region’s vast grasslands.



APR BioBlitz Report (2011)

On June 23-25, 2011, the American Prairie Reserve held their first BioBlitz. In just 24 hours a list of 550 species was created by approximately 70 scientists, college students, citizen scientists, and volunteers. The number of documented species was only limited by the number of taxonomic experts we could get to join this project in such a remote location. The species list will serve as a benchmark of the biodiversity in the early years on the Reserve.



Bird Surveys Report (2009)

A study funded by World Wildlife Fund and conducted by Wild Things Unlimited surveyed the number of different species types, the number of individuals within each species and species distribution throughout the area’s grasslands, sagebrush communities, prairie dog towns and wetlands in 2005, 2009, and 2013. A total of 159 species were observed on APR in 2013 (up from 132 in 2009), including 14 species not seen in previous years. Breeding bird surveys will resume in 2016 with Clemson University.  



Riparian Restoration Summary

In Spring 2007, APR, World Wildlife Fund, Oxbow Inc. and Hoitsma Ecological restored a half-mile segment of Box Elder Creek that has been farmed as an alfalfa field at least 70 years prior. Supported by a grant from Montana Fish Wildlife & Parks’ Future Fisheries Fund, the restoration project involved digging a new channel that reconnects Box Elder’s 27-square mile watershed to Telegraph Creek. A Montana Conservation Corps group supported the project by installing 1,500 plants along the channel. The same year, three dams were removed on Telegraph Creek to help restore natural flows and connectivity. Read more about stream restoration. 



WCS Birds and Grazing Report (2009)

Starting in 2009, the Wildlife Conservation Society surveyed sites with different grazing practices to better understand the relationships between grazing, habitat structure, and habitat use by grassland birds. The study included Reserve lands as well as sites on private ranches and lands owned by The Nature Conservancy and Nature Conservancy Canada.



APR Fish Surveys Report (2012)

Fish surveys were conducted in the Telegraph Creek basin in 2006, 2008, 2011, and 2012. Water levels varied widely during these times and dam removals also occurred in 2007. The latest report from Kayhan Ostovar of Rocky Mountain College examines how the removal of fish barriers and the new connectivity to Fort Peck Reservoir, which is stocked with nonnative fishes, may have impacted the distribution and species composition of the Telegraph Creek.



Beavers of the American Prairie Restoration Area

In 2005, World Wildlife Fund’s Northern Great Plains Program examined historic occupation by beaver in the project areas, assessed the hydrological and biological impacts of beaver activity in prairie streams, and summarized beaver restoration techniques in similar environments. The report suggests that the presence of beaver in the region would provide significant benefits to riparian corridors, water levels, and related animals.



Read the 2018 academic study and see maps.

In 2012, graduate researcher Andrew Jakes led a study that was conducted by World Wildlife Fund, Montana Fish, Wildlife & Parks, University of Calgary, the Bureau of Land Management, and the Saskatchewan Ministry of Environment. The study focused on the ecological impact of human activities such as oil and gas development, roadway building, windmill development and other activities that lead to the fragmentation of pronghorn habitat on the Northern Great Plains. Read more. 

Fencing for Conservation, Chapter 15: The Influence of Land Use and Fences on Habitat Effectiveness, Movements and Distribution of Pronghorn in the Grasslands of North America. Authored by C. Cormack Gates, Paul Jones, Michael Suitor, Andrew Jakes, Mark S. Boyce, Kyran Kunkel, and Kevin Wilson. 



Read the 2012 report about cougars in northcentral Montana

The U.S. Fish and Wildlife Service in collaboration with Montana Fish, Wildlife and Parks, Rocky Boy’s Reservation, Fort Belknap Reservation, the Montana Cooperative Wildlife Research Unit and the World Wildlife Fund, conducted a research project to better understand mountain lion ecology on the Charles M. Russell National Wildlife Refuge and surrounding areas. More than a dozen mountain lions were fitted with GPS in the nearby Bears Paw Mountains, Little Rocky Mountains, and the refuge. Findings indicate that the region’s cougar population is not sustainable over the long term. Read more about cougars. 



World Wildlife Fund Swift Fox Report (2010)
Swift Fox Conservation Assessment Strategy (2011)

In 2010, World Wildlife Fund conducted a survey for foxes on and around American Prairie Reserve and found none. It was recommended that we reintroduce foxes to the area. Learn about our current efforts.



Bowers, Cedarbaum, Day, Macaskill: Feasibility of Establishing a Conservation Bank to Benefit Greater Sage-Grouse in Montana (2017)
Womack, Jennifer Marie: Evaluation of the Hydrologic Effects of Stock Ponds on a Prairie Watershed (2012)
Kohl, Michel Thomas: Bison Conservation in the Northern Great Plains (2008)
Charboneau, Joseph L.M.: A Floristic Inventory of Phillips and Valley Counties, Montana, USA (2013)
McMillan, Nicholas: Plant Community Responses to Bison Reintroduction Within Montana's Northern Great Plains (2017)