Northern Research Station News Releases
Condition varies with habitat choice in postbreeding forest birds
Forest-interior Birds May be Benefiting from Harvested Clearings
Irvine, PA, August 21, 2013 - Efforts to conserve declining populations of forest-interior birds have largely focused on preserving the mature forests where birds breed, but a U.S. Forest Service study suggests that in the weeks leading up to migration, younger forest habitat may be just as important.
In an article published recently in the American Ornithologist Union’s publication “The Auk,” research wildlife biologist Scott Stoleson of the U.S. Forest Service’s Northern Research Station suggests that forest regrowth in clearcuts may be vital to birds as they prepare for fall migration. The article, “Condition Varies with Habitat Choice in Postbreeding Forest Birds,” is available at: http://www.nrs.fs.usda.gov/pubs/43984
The study suggests that declines in forest-interior species may be due in part to the increasing maturity and homogenization of forests. Openings created by timber harvesting may increase habitat for some forest interior birds, according to Stoleson. “Humans have really changed the nature of mature forests in the Northeast,” Stoleson said. “Natural processes that once created open spaces even within mature forests, such as fire, are largely controlled, diminishing the availability of quality habitat.”
On four sites on the Allegheny National Forest and private timber inholdings in northeastern Pennsylvania, Stoleson set out to learn where the birds spend time after breeding season and what kind of condition are they in leading up to migration. “After the breeding season, birds sing less, stop defending territory, and generally wander. Tracking them is challenging at this point in their life cycle,” Stoleson said. Between 2005 and 2008, he used constant-effort mist netting to capture songbirds, band them, determine whether they were breeding or postbreeders, and assess their overall condition, including whether they were building fat deposits and the extent of parasites the birds carried.
In 217 days of netting birds over the course of the 4-year study, Stoleson netted and banded a total of 3,845 individuals. Of these, 2,021 individuals representing 46 species were in the postbreeding stage, based on physiological criteria. Of these, 33 percent were mature-forest specialists, 22 percent were forest-edge species, and the remaining 45 percent were early-successional specialists. All 46 species were captured in cuts, but only 29 species were captured within forest.
Stoleson’s research concluded birds’ use of young forest in the postbreeding season is correlated with better physiological condition for some forest birds, which suggests that the maintenance of such early-successional habitats in mature forest may benefit these species. Study results did not find a correlation between habitat and the presence of fat or parasites.
“Forest Service science contributes directly to healthy, sustainable forests that are more productive and, ultimately, produce cleaner air and water. Birds can help. Research has demonstrated that forest birds, through seed distribution and insect control, play a vital forest stewardship role,” said Michael T. Rains, Director of the Northern Research Station and Forest Prodratory.
The mission of the U.S. Forest Service is to sustain the health, diversity, and productivity of the nation’s forests and grasslands to meet the needs of present and future generations. The agency has either a direct or indirect role in stewardship of about 80 percent of our nation’s forests; 850 million acres including 100 million acres of urban forests where most Americans live. The mission of the Forest Service’s Northern Research Station is to improve people’s lives and help sustain the natural resources in the Northeast and Midwest through leading-edge science and effective information delivery.
The U.S. Forest Service is an agency of the U.S. Department of Agriculture, a mission of sustaining the health, diversity and productivity of the nation’s forests and grasslands to meet the needs of present and future generations. The mission of the Forest Service's Northern Research Station is to improve people’s lives and help sustain the natural resources in the Northeast and Midwest through leading-edge science and effective information delivery.
The U.S. Forest Service manages 193 million acres of public land, provides assistance to state and private landowners, and maintains the largest forestry research organization in the world. Public lands the Forest Service manages contribute more than $13 billion to the economy each year through visitor spending alone. Those same lands provide 20 percent of the nation’s clean water supply, a value estimated at $7.2 billion per year. The agency has either a direct or indirect role in stewardship of about 80 percent of the 850 million forested acres within the U.S., of which 100 million acres are urban forests where most Americans live. For more information, visit www.fs.usda.gov/.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, religion, sex, gender identity (including gender expression), sexual orientation, disability, age, marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines vary by program or incident. Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American Sign Language, etc.) should contact the responsible Agency or USDA’s TARGET Center at (202) 720-2600 (voice and TTY) or contact USDA through the Federal Relay Service at (800) 877-8339. Additionally, program information may be made available in languages other than English. To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, found online at https://www.ascr.usda.gov/complaint_filing_cust.html and at any USDA office or write a letter addressed to USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call (866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410; (2) fax: (202) 690-7442; or (3) email: firstname.lastname@example.org.
USDA is an equal opportunity provider, employer and lender.