Northern harrier
Northern harrier | |
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Adult female | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Accipitriformes |
Family: | Accipitridae |
Genus: | Circus |
Species: | C. hudsonius
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Binomial name | |
Circus hudsonius (Linnaeus, 1766)
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Breeding
Year-round
Nonbreeding
Migration
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Synonyms | |
Circus cyaneus hudsonius |
The northern harrier (Circus hudsonius), also known as the marsh hawk or ring-tailed hawk, is a
.The northern harrier migrates south in winter, with breeding birds in Canada and northern Great Plains of the U.S. moving to the American south, Mexico, and Central America. In the midwestern, mountain west, and north Atlantic states of the U.S., they may be present all year. This bird inhabits prairies, open areas, and marshes.
Taxonomy
In 1750 the English naturalist
The northern harrier was formerly considered to be
Description
The northern harrier is 41–52 cm (16–20 in)[9] long with a 97–122 cm (38–48 in) wingspan. It resembles other harriers in having distinct male and female plumages. The sexes also differ in weight, with males weighing 290 to 400 g (10 to 14 oz), with an average of 350 g (12 oz), and females weighing 390 to 750 g (14 to 26 oz), with an average of 530 g (19 oz).[9][10] Among standard measurements, the wing chord is 32.8 to 40.6 cm (12.9 to 16.0 in), the tail is 19.3 to 25.8 cm (7.6 to 10.2 in) and the tarsus is 7.1 to 8.9 cm (2.8 to 3.5 in).[10] It is relatively long-winged and long-tailed, having the longest wing and tail relative to its body size of any raptor occurring in North America.[10]
The northern harrier breeds in North America, and its closest relative is the
The female gives a whistled piih-eh when receiving food from the male, and her alarm call is chit-it-it-it-it-et-it. The male calls chek-chek-chek, with a more bouncing chuk-uk-uk-uk during his display flight.
Behaviour
This medium-sized raptor breeds on moorland, bogs, prairies, farmland coastal prairies, marshes, grasslands, swamps and other assorted open areas.[13] A male will maintain a territory averaging 2.6 km2 (1.0 sq mi), though male territories have ranged from 1.7 to 150 km2 (0.66 to 57.92 sq mi).[14]
These are one of the few raptorial birds known to practice polygyny – one male mates with several females. Up to five females have been known to mate with one male in a season.[15] The nest is built on the ground or on a mound of dirt or vegetation. Nests are made of sticks and are lined inside with grass and leaves. Four to eight (exceptionally 2 to 10) whitish eggs are laid.[9][13] The eggs measure approximately 47 mm × 36 mm (1.9 in × 1.4 in).[16] The eggs are incubated mostly by the female for 31 to 32 days. When incubating eggs, the female sits on the nest while the male hunts and brings food to her and the chicks.[13] The male will help feed chicks after they hatch, but does not usually watch them for a greater period of time than around 5 minutes.[17] The male usually passes off food to the female, which she then feeds to the young, although later the female will capture food and simply drop into the nest for her nestlings to eat.[14] The chicks fledge at around 36 days old, though breeding maturity is not reached until 2 years in females and 3 years in males.
Hunting behavior
This is a typical harrier, which hunts on long wings held in a shallow V in its low flight during which the bird closely hugs the contours of the land below it. Northern or hen harriers hunt primarily small
Mortality and competition
Little information is available on longevity in northern harriers. The longest lived known bird is 16 years and 5 months. However, adults rarely live more than 8 years. Early mortality mainly results from predation. Predators of eggs and nestlings include
Status
This species has a large range, and there is evidence of a population decline, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e., declining more than 30% in ten years or three generations). It is therefore classified as "least concern".[1]
Relationship with humans
Some Native American tribes[
References
- ^ . Retrieved 19 November 2021.
- ^ Edwards, George (1750). A Natural History of Uncommon Birds. Vol. 3. London: Printed for the author at the College of Physicians. p. 107, Plate 107.
- ^ Linnaeus, Carl (1766). Systema naturae : per regna tria natura, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (in Latin). Vol. 1, Part 1 (12th ed.). Holmiae (Stockholm): Laurentii Salvii. p. 128.
- ^ Lacépède, Bernard Germain de (1799). "Tableau des sous-classes, divisions, sous-division, ordres et genres des oiseux". Discours d'ouverture et de clôture du cours d'histoire naturelle (in French). Paris: Plassan. p. 4. Page numbering starts at one for each of the three sections.
- ^ Rasmussen, Pamela, eds. (January 2022). "Hoatzin, New World vultures, Secretarybird, raptors". IOC World Bird List Version 12.1. International Ornithologists' Union. Retrieved 9 June 2022.
- ISBN 978-1-4081-2501-4.
- .
- .
- ^ ISBN 978-84-87334-15-3.
- ^ ISBN 978-0-7136-8026-3.
- ^ "If you've seen a Northern Harrier in flight, you know they are beautiful". Kawartha Lakes This Week. Lindsay, Ontario. June 11, 2018.
- ^ Zimmer, David M. (October 20, 2014). "Historic Farm Holds Growing Appeal". The Record. Bergen County, New Jersey. p. L.6.
- ^ a b c d e f "Northern Harrier (Circus cyaneus)". Wildlife Fact Sheets. Texas Parks and Wildlife Department. Retrieved 25 June 2012.
- ^ a b Macwhirter, R.; Bildstein, K. (1996). Northern Harrier. The Birds of North America. pp. 1–25.
- ^ "Northern Harrier". All About Birds. Cornell Lab of Ornithology. Retrieved 23 August 2012.
- ISBN 978-0120728312.
- ISBN 978-1-55821-275-6.
- ISBN 978-0874170801.
- .
- ISBN 978-0713667639.
- ^ "Short-eared Owl – Asio flammeus". owlpages.com. 24 July 2013. Retrieved 1 December 2015.
External links
- Northern Harrier Species Account – Cornell Lab of Ornithology
- Northern Harrier photo gallery at VIREO (Drexel University)