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U.S. Hwy. 421 Closure in Effect- Mar. 24- late April

On or after Monday, March 24, U.S. Hwy. 421 will be closed just north of State Route 250 for replacement of a small structure structure
Something temporarily or permanently constructed, built, or placed; and constructed of natural or manufactured parts including, but not limited to, a building, shed, cabin, porch, bridge, walkway, stair steps, sign, landing, platform, dock, rack, fence, telecommunication device, antennae, fish cleaning table, satellite dish/mount, or well head.

Learn more about structure .  Work should be complete by the end of April, weather permitting.  The official detour is State Route 7 to U.S. Hwy. 50.

Historical land use practices have created unique habitat at Big Oaks National Wildlife Refuge for many rare and uncommon species of animals and plants. The 50,000 acres of land has been designated as a Globally Important Bird Area.
Big Oaks Winter Hours

Big Oaks is closed to public use now but will reopen April 18, 2025.

Visit Us

Wooded creek
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For a first visit to Big Oaks National Wildlife Refuge, please allow at least an hour to stop at the office, take the safety briefing and obtain a daily pass. That’s also a great time to talk with the staff about activities available on the refuge, pick up a refuge map, and find out about current wildlife sightings.  

Location and Contact Information

Marker

    Tours

    The refuge offers guided tours by van throughout the public use season. Special guided tours can be requested for birding, wildflower hikes, and historical tours of the property. Visitors can also schedule tours of the historic Old Timbers Lodge.  For more information call the refuge Office. Tours of the refuge could be restricted due to pandemic restrictions.

    What We Do

    Cerulean warbler on tree branch
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    Wildlife and habitat management, especially for rare and endangered species, are the priorities for Big Oaks staff. Various kinds of surveys and monitoring take place annually on the refuge, usually in cooperation with local universities.  Past projects have included monitoring endangered Indiana bats, American burying beetles, and American kestrels. Volunteers and interns have assisted with many surveys of forest and grassland bird nest productivity, cerulean warbler nesting ecology, and small mammal biodiversity.  The most recent and on-going project on the refuge is providing habitat for monitoring the state-endangered crawfish frog.

    Services
    Entrance sign at Big Oaks National Wildlife Refuge
    Big Oaks National Wildlife Refuge User Fees

    Activities at Big Oaks require paying either a daily fee of $3 for a public access permit or $15 for an annual access permit with certain exceptions. Holders of a Federal Duck Stamp do not need to pay a fee or does anyone age 15 and under. Holders of Federal Interagency Senior, Access, and...

    Service
    Permits

    Our Organization

    A bright blue sky obstructed by fluffy white clouds reflected off of a stream shot from inside a kayak
    The U.S. Fish and Wildlife Service manages an unparalleled network of public lands and waters called the National Wildlife Refuge System. With more than 570 refuges spanning the country, this system protects iconic species and provides some of the best wildlife viewing opportunities on Earth.
    Program
    Washington,DC

    Our Species

    Henslow sparrow singing from grass stem
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    Big Oaks National Wildlife Refuge is a Globally Important Bird Area and hosts one of the world’s largest populations of Henslow’s sparrows. The refuge also provides nesting habitat for cerulean warblers, temporary wetlands and grasslands for state endangered crawfish frogs and habitat for many other rare species of animals and plants.

    Projects and Research

    Adult crawfish fog on ground at Big Oaks NWR
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    Big Oaks has been monitoring and managing for the state endangered crawfish frog for many years.  Other research projects have included the monitoring of Indiana bats, saw-whet owls,American burying beetles, and American kestrels.

    Northern saw whet owl perched on branch
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    Northern saw-whet owls migrate through Indiana every fall and banding has taken place at Big Oaks for many years to learn more about the owl's distribution and abundance. Banding takes place on nights in early Novem ber where the birds are caught in mist nets (similar to a fine mesh tennis net).