Endangered Northern Harrier Monitoring Success in 2020
Article by Chris Martin
Photos right: Scott Kalter photographed this pair of Northern Harriers at a nest site in Lyme where he watched them for over a month. The nest failed for unknown reasons. Scott’s five photos on the right are of a prey exchange between the male (the gray individual) and the female (the brown bird) on 5-23-20.
NH Audubon began fieldwork in Summer 2019 designed to update the breeding status of state-endangered Northern Harriers in New Hampshire. Since work got started in the midst of the nesting season with limited funding we struggled in 2019 to confirm just one successful breeding pair at Pondicherry Wildlife Refuge.
It was quite a different story in 2020, with State Wildlife Grant (SWG) funds from NH Fish and Game sufficient to cover the full 2020 breeding season. What a difference a year (and adequate funding) makes!
In 2020, we confirmed at least 10 Northern Harrier breeding territories scattered across the state. Most sites were in Coos County, but we found three territories located south of the White Mountains (Conway, Lyme, and Tuftonboro). Four pairs were unsuccessful, but six successful pairs fledged a total of at least nine young, including four pairs in Coos County (Colebrook, Dummer, and Stewartstown (2)), as well as two pairs nesting in Carroll County. Notably, we did not find any territorial pairs in seemingly suitable habitat in Pittsburg, at Umbagog National Wildlife Refuge in Errol, or anywhere along the New Hampshire seacoast.
NH Audubon was fortunate to hire seasonal biologist Katrina Fenton starting in early May to track Coos County harrier activity starting with their return to breeding territories. Spring observations of courting harriers can be especially useful, since both members of a territorial pair are active and vocal, and engage in nest-building while the surrounding ground vegetation is low and nearby shrubs have not yet leafed out. Spring observations can also help us confirm breeding attempts that ultimately fail.
Levi Burford joined our team effort in July, as we focused on documenting prey deliveries to hidden nests and confirming presence of fledglings. Watching from a distance, our biologists obtained cross-bearings on activity hotspots, allowing us to pinpoint nests in what otherwise was rather nondescript field or marsh habitat.
In August, juvenile harriers finally revealed themselves after weeks concealed in their nests, and we spent the first half of the month “counting kids.” Awkward fledglings began to pop up in places we had been watching all summer, places where adult harriers had repeatedly performed aerial prey transfers or lingered watchfully on dead snags or old cedar fence posts. Katrina first spotted three fledglings at Pontook Reservoir during the first week of August, and more airborne juveniles soon followed at other sites in both Coos and Carroll counties.
Katrina and Levi both did great work walking two-track paths through hayfields, scouring dense cattail marshes, and exploring maze-like Christmas tree farms. They logged hundreds of hours and many miles patiently search for these beautiful birds.
Thanks as well to our volunteers who watched at other sites, and several other birders who documented nesting attempts on eBird. We are already looking forward to beginning another field season in Spring 2021!
Photo bottom left: A female Northern Harrier at one of the Coos County nest sites, 4-29-20, by Lori Charron.
Photo bottom right: A female Northern Harrier carrying nesting material and being chased by a Red-winged Blackbird on 6-5-20 at the Pontook Reservoir, Dummer, NH. Photo by Lori Charron.
