Places We Protect

Oka' Yanahli Preserve


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

Meaning "flowing water" in Chickasaw, this preserve protects two miles of the Blue River, one of only two free-flowing rivers in Oklahoma.



The Oka’ Yanahli Preserve stretches across 3,600 acres of native prairie which protects the valuable resources of the iconic Blue River and Arbuckle-Simpson Aquifer

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 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. 

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 which is home to Southeastern Oklahoma State University, the headquarters of the Choctaw Nation and is ranked the fastest growing rural city in Oklahoma.



Limited access during events.


Johnston County

Map with marker: The Oka' Yanahli Preserve is located within Johnston County, Oklahoma.


Endemic species, Blue River, Native prairie, Bottomland hardwood forests, Aquifer recharge zone


3,600 acres

Explore our work in Oklahoma

Photos from NatGeo Photo Ark

Discover the unique endemic species of the Oka' Yanahli and Pontotoc Ridge Preserves photographed by Joel Sartore National Geographic Photo Ark project.

Orangebelly darter on a white background.
Big-eyed toad bug on black background.
Orangebelly darter on black background.
Ringed crayfish on a white background.
BIgeye shiner on black background.
Ringed crayfish on black background.
Bigeye shiner on white background.
Hellgrammite photographed on a white background.
Damselfly larvae on black background.
Western pygmy rattlesnake on a white background.
Map of Oklahoma preserves in OK360 virtual tour.
OK360 Take a virtual field trip to Oklahoma's 5 flagship preserves. © TNC

Immerse Yourself in Nature

Take a virtual field trip and experience breathtaking 360° panoramas of Oklahoma’s native and diverse landscapes. Great for classrooms and living rooms alike to learn about the unique Oka' Yanahli Preserve in southeastern Oklahoma and all its plants, animals, and special ecology through this engaging multi-media.

Take a Virtual Field Trip

Nearby Preserves

Need more nature? Visit The Nature Conservancy's other preserves in Oklahoma.

Find More Places We Protect

The Nature Conservancy owns nearly 1,500 preserves covering more than 2.5 million acres across all 50 states. These lands protect wildlife and natural systems, serve as living laboratories for innovative science and connect people to the natural world.

See the Complete Map

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