This project aims to better understand the habitat needs, movement patterns, and conservation challenges facing this state-threatened grassland raptor.
Beginning in 2026 and continuing through 2029, Hawk Mountain researchers will conduct a two-part study combining statewide habitat analysis with satellite tracking technology.
Researchers will locate nesting pairs statewide and along with years of verified sightings from eBird, the Pennsylvania Bird Atlas, and Hawk Mountain’s Farmland Raptor Project database, use this combined data to understand how land cover, development, and fragmentation may affect harrier populations across the state.
The project will also involve capturing and tagging adult or juvenile harriers with lightweight GSM transmitters to map home ranges, migration routes, and wintering grounds.
The tracking data will provide insight into how Pennsylvania harriers use the landscape throughout the year and how development pressures may influence nesting success and survival.
Northern Harrier Habitat
Once widespread across Pennsylvania’s open fields and marshes, northern harriers have experienced steep declines in recent decades due to habitat loss, fragmentation, and changing land use.
Known for their low, sweeping flight over grasslands and marshes, northern harriers nest directly on the ground in tall grasses or marsh vegetation to hide their young from predators-- a habit that exposes them to being mown over as these landscapes have been converted to hay fields.
Because they require these large expanses of open habitat to successfully raise young, they serve as important indicators of healthy grassland ecosystems that also support species such as bobolinks, dickcissels, and short-eared owls.
Pennsylvania Bird Atlas data documented a dramatic reduction in nesting distribution between the 1980s and 2010, with some estimates showing losses of 43%, while populations across eastern North America have declined by more than 30 percent.
“Northern harriers are one of Pennsylvania’s most unique and vulnerable raptors, but there is still so much we don’t know about their breeding ecology and habitat needs within the state,” says Bracken Brown, Biologist-Naturalist at Hawk Mountain Sanctuary. “This project will help us identify what landscapes are most important for harriers and how we can better protect those habitats for the future.”
Resident Participation Critical
Community participation will play a major role in the project’s success.
Hawk Mountain is asking landowners and residents across Pennsylvania to report northern harrier sightings between May and July, particularly in areas with extensive grassland or marsh habitat.
Observers should look for a low-flying hawk with long wings, a distinctive white rump patch, and owl-like facial features.
Males are pale gray, while females are warm brown with heavy brown-streaked chests.
Researchers are especially interested in reports of repeated activity over fields or evidence of nesting behavior.
“Because harriers are secretive nesters and can occur across large rural landscapes, local observations are incredibly valuable,” Brown explains. “Landowners and community members can directly contribute to conservation simply by sharing sightings or information about historic harrier use on their property.”
Click here to learn more about the project.
Click Here to submit sightings online.
Questions and inquiries can be directed to Bracken Brown at brackenbrown@hawkmountain.org or 570-943-3411 ext. 103.
This research is supported through grants from the Department of Conservation and Natural Resources Wild Resources Conservation Program and the Game Commission, along with private support for tracking transmitters.
The 2,500-acre Hawk Mountain Sanctuary is the world’s first refuge for birds of prey and is open to the public year-round by trail-fee or membership, which in turn supports the nonprofit organization’s raptor conservation mission and local-to-global research, training, and education programs.
[Posted: June 1, 2026] PA Environment Digest
No comments :
Post a Comment