Places We Protect

Oka' Yanahli Preserve


The Blue River at Oka' Yanahli Preserve
The Blue River at Oka' Yanahli Preserve © Mike Fuhr/TNC

Oka’ Yanahli Preserve stretches along two miles of the Blue River, one of only two free-flowing rivers in Oklahoma.



Take a virtual field trip of Oklahoma Preserves, including Oka' Yanahli Preserve.

In southern Oklahoma, along two-miles of the Blue River, sits 3,600 acres of native prairie, the Oka’ Yanahli Preserve. The Blue River is an iconic symbol of natural beauty and a precious resource for life and economic development - a resource worth protecting.

Life-Giving Water

The Blue River and the Arbuckle-Simpson Aquifer, which sustains the river, are globally significant for the wide assortment of endemic life they support. The Blue River basin encompasses a variety of freshwater ecosystems, from rolling prairies, limestone outcrops, oak forests in granite canyons to bottomland hardwood forests. An astonishing array of plant and animal species depend on a healthy, sustainable basin, including the subspecies of orangebelly darter, orangethroat darter and least darter; ringed crayfish; rabbitsfoot mussel; chatterbox orchid; bald eagle, prothotary warbler and dozens of species of migrating birds. Seaside alder, found only in three widely disjunct parts of the United States—and arguably the rarest tree in North America—is more abundant on this river than anywhere else. The Blue River has shaped human history in Oklahoma and continues to be a source of life and biodiversity. 

This Blue River is also a critical source of water for human needs. In addition to providing for agriculture, the river sustains the City of Durant. Durant is home to Southeastern Oklahoma State University, the headquarters of the Choctaw Nation of Oklahoma and is ranked the fastest growing rural city in Oklahoma.

Conservation In Action

At the Oka’ Yanahli Preserve we are working to restore and protect native grasslands, stream side vegetation, bottomland forests, wetland hydrology, springs, seeps, and floodplain habitats, control non-native vegetation such as the eastern red cedar, sericea lespedeza and feral hogs, and improve inflow patters of the river.

In addition, we are pursuing conservation easements in the river corridor and encouraging landowners to adopt methods that will enhance the quantity and quality of the water in the Blue River. Approximately 97% of the Blue River watershed is privately owned; nonetheless, we aspire to create a resilient water supply for all users. A healthy water system is important for fish and wildlife as well as people. It is also critical to the local and regional economy. 

We believe that human needs can be met without sacrificing the health of the freshwater systems upon which all life depends. The Blue River offers a perfect example of conservation for people and nature. Our work on the Blue River will provide a template for restoration, sustainable use, education and protection. We will continue bringing partners together to synchronize their actions in a way that will sustain the natural environment while providing water for people. At a time when the entire region is concerned about the future of its freshwater supply, this project can set the bar for the state on collaborative water conservation.

Access is limited to personnel and is open for public visitation during events hosted by The Nature Conservancy such as our field trips.



This preserve is closed to the public.


Johnston County, OK

Map with marker: Oka' Yanahli Preserve is periodically open during TNC hosted events. Visit our events page to view upcoming schedule.

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Take a virtual field trip to Oklahoma's 5 flagship preserves.
OK360 Take a virtual field trip to Oklahoma's 5 flagship preserves. © TNC

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Take a virtual field trip and experience breathtaking 360° panoramas of Oklahoma’s native and diverse landscapes. Take a trek through the limestone glades and wildflowers at The Nature Conservancy's Pontotoc Ridge Preserve and learn about Oklahoma’s plants, animals, and ecology via engaging multi-media.

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