Nature Lab

How Do Birds and Forestry Mix?

Biologists are studying how forestry in the Ozarks affects bird populations over time

The oak-hickory-pine forests of Missouri’s Ozarks are critical for many species of migratory birds. To keep these forests healthy as they age, management is required. But how do birds respond to forest management? The Missouri Ozark Forest Ecosystem Project (MOFEP) is helping to answer this and related questions.

MOFEP is a large-scale, 100-year experiment to study how wildlife and other ecosystem components respond to three common types of management: even-aged (creates a patchwork of similar-aged trees), uneven-aged (creates a mixture of tree ages), and no harvest (leaves mature forest untouched). Portions of even-aged and uneven-aged sites are harvested every 15–20 years.

“The research started in 1991 and that’s when the bird project started,” says MDC Avian Ecologist Janet Haslerig, who leads the MOFEP bird study.

Except for harvest years (1996 and 2011), surveys for bird abundance and nesting have been completed annually. All species are recorded, but analyses focus on 11 that breed in the Ozarks and migrate south for winter. Five nest in mature forests and six in young forest habitat.

“As you might suspect, when we harvest trees, we see a reduction in mature-forest birds,” Haslerig reports, “but young-forest species increase because they like the shrubby vegetation that grows in areas that have been cut. Without management creating a range of forest ages, we wouldn't have the habitat to support the young-forest species.”

But as the vegetation matures, the numbers change. Young-forest species peak within seven years of harvest and then begin declining.

These data measure the localized response of birds to tree harvests and forest regrowth, but over time, MOFEP will show how birds respond at the landscape scale. Although the project has many decades to go, the current 30 years of data still offer “lessons learned,” Haslerig says, that can be applied when managing for forest songbirds.

“MOFEP is nationally and internationally recognized as one of the most comprehensive forest management studies in North America,” she says. “It has shown that we can create habitat for birds as well as maintain healthy forests.”

At a Glance

The MOFEP bird study looks at how 11 focal species respond to different forest management systems in the Ozarks. 

• Mature-forest species: Acadian flycatcher, Kentucky warbler, ovenbird, wood thrush, worm-eating warbler
• Young-forest species: blue-winged warbler, hooded warbler, prairie warbler, indigo bunting, white-eyed vireo, yellow-breasted chat

Partners

Central Methodist University, Pittsburg State University, University of Missouri