Northern Harrier

It is a joy to see a Northern Harrier, with its owl-like face, gracefully coursing low over an open field in search of an unsuspecting mouse (Mus musculus) or vole (Microtus arvalis). It is especially thrilling in Virginia, where the Northern Harrier is a rare breeder but commonly observed migrant and winter resident in the state’s coastal region, primarily observed on the Eastern Shore (Watts and Rottenborn 2007). In fall 2023, volunteers at The Rockfish Gap Hawk Watch counted 57 migrating Northern Harriers, which was less than the 10-year average of 67 (RGHW 2023). In general, Northern Harriers occur to the north and west of Virginia, where they breed in open habitats, such as prairies (Smith et al. 2020).

Breeding Distribution

During the Second Breeding Bird Atlas, there were too few breeding observations to develop occurrence models for the Northern Harrier. Please see the Breeding Evidence section for more information on breeding distribution.

Breeding Evidence

The Northern Harrier was a confirmed breeder in just one location when an adult was observed feeding young in Accomack County on the Eastern Shore of Virginia on July 4 (Figure 1). In addition, there were nine observations of possible breeding (Accomack, Augusta, Bedford, Richmond, and Shenandoah Counties and the city of Poquoson), but none of the observations could be elevated to a probable status when reviewed. During the First Atlas, there were only two confirmed breeders, one in Accomack County and one in the city of Poquoson (Figure 2).

For more general information on the breeding habits of this species, please refer to All About Birds.

Figure 1: Northern Harrier breeding observations from the Second Atlas (2016–2020). The colored boxes illustrate Atlas blocks (approximately 10 mi² [26 km²] survey units) where the species was detected. The colors show the highest breeding category recorded in a block. The numbers within the colors in the legend correspond to the number of blocks with that breeding evidence category.

Figure 2: Northern Harrier breeding observations from the First Atlas (1985–1989). The colored boxes illustrate Atlas blocks (approximately 10 mi² [26 km²] survey units) where the species was detected. The colors show the highest breeding category recorded in a block. The numbers within the colors in the legend correspond to the number of blocks with that breeding evidence category.

Figure 3: Northern Harrier phenology: confirmed breeding codes. This graph shows a timeline of confirmed breeding behaviors. Tick marks represent individual observations of the behavior.

Population Status

As it is a rare breeder in the state, a lack of detections during point count surveys prevented the development of an abundance model for the Northern Harrier. Additionally, Northern Harriers are not regularly observed during North American Breeding Bird Surveys (BBS), so reliable BBS trends could not be calculated. However, based on state-level surveys, of the 25 documented pairs in Coastal Plain in the 1990s, only a quarter currently remain, and they may have moved inland, breeding in agricultural fields (Bryan Watts, personal communication). They are considered a small population at the edge of their breeding range.

Conservation

Northern Harriers remain common throughout their breeding range, but the population has been exhibiting a steady one percent annual decline since 1966 (Sauer et al. 2022). Like other obligate grassland nesting birds, the Norther Harrier is threatened by habitat loss, owing to human development and changes in agricultural practices, such as a move away from hay and pasture lands toward intensive row-crop farming (Smith et al. 2020). As such, the 2025 Virginia Wildlife Action Plan classifies the wintering population as a Tier III Species of Greatest Conservation Need (High Conservation Need), indicating management actions are needed (VDWR 2025).

Interactive Map

The interactive map contains up to six Atlas layers (probability of occurrence for the First and Second Atlases, change in probability of occurrence between Atlases, breeding evidence for the First and Second Atlases, and abundance for the Second Atlas) that can be viewed one at a time. To view an Atlas map layer, mouse over the layer box in the upper left. County lines and physiographic regional boundaries (Mountains and Valleys, Piedmont, and Coastal Plain) can be turned on and off by checking or unchecking the box below the layer box. Within the map window, users can hover on a block to see its value for each layer and pan and zoom to see roads, towns, and other features of interest that are visible beneath a selected layer.

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References