Ring-Tail Marsh Hawks (Circus hudsonius): Female and Juvenile Harriers of the Western Hemisphere

by DerdriuMarriner

Harrier hawks are native to Africa, America, and Eurasia. Only a female or juvenile carries the designation "ring-tail." Only in America is either known as ring-tail marsh hawk.

The Western Hemisphere accommodates the survival needs of marsh harrier hawks. Harriers are particularly visible in continental North America, from breeding grounds in mainland Canada and the United States of America to residence winters in Mexico or year-round in the Southern States. They additionally can be viewed as winter nomads in Caribbean, Central and South America. Harrier hawks nevertheless do not tend to venture further south than the northern fringes of:
• Colombia;
• Ecuador;
• Venezuela.

They excel at surviving bi-annual long-distance flights. Older and younger marsh harriers even manage to survive rare off-coursing respectively east- and west-ward to:
• The Hawaiian and Japanese archipelagos of the Pacific Ocean;
• The Portuguese Autonomous Region of the Azores in the Atlantic Ocean.

Native ranges of Circus cyaneus (Africa and Eurasia) and Circus hudsonius (North America)

Light Green - nesting area; Dark Green - resident all year; Blue - wintering area
Light Green - nesting area; Dark Green - resident all year; Blue - wintering area

 

Harrier hawks are not specific to Scandinavian countries or to Scandinavian diasporas. Their name nevertheless comes from anguished depictions of Viking activities in England. The word harrier in fact dates back to the ninth century. It emerges in chronologically organized, event-oriented annals consolidated by an unknown scribe into the Anglo-Saxon Chronicle, whose publication is suspected as first occurring in England's southern half -- excluding Wales -- during the reign of Wessex's King Alfred the Great (birth 849; succession April 23, 1871; death October 26, 899). Through its etymological origins in the Old English verb hergian, it expresses the viewpoint of coastal peoples traumatized by Vikings (Old Norse for “oversea expedition”) laying waste, making war, plundering, and ravaging.

The term in its original meaning does not describe harrier hawk behavior. It does serve as an accurate designation in its evolved meaning. Since the fifteenth century, the term particularly expresses the sustained commitment to wearing down a competitor, enemy or prey through goading, harassing, and worrying. It therefore is descriptive of the harrier hawk’s patient persistence in food fights and predatory flights. For example, the harrier hawk lives in the same habitats as the short-eared owl (Asio flammeus). Each one may be accused of kleptoparasitism -- from the Greek verb κλέπτω (kleptō) for “to steal” -- in bothering one another until the predator with first claim drops the prey and flees. The harrier hawk usually prevails.

 

short-eared owl (Asio flammeus):

usually loses in atavistic, kleptoparasitic game of "predator, predator, who's got the prey?" with harrier hawk
British Wildlife Centre, Newchapel, Surrey, South East England
British Wildlife Centre, Newchapel, Surrey, South East England

 

Marsh harrier hawks answer to many common names:

  • Aguilucho americanoaguilucho norteñoaguilucho pálidogavilán de ciénagagavilán pantanerogavilán rasterogavilán rastrero, and gavilán sabanero in Spanish;
  • American harrier, North American harrier, northern harrier, and white-rumped harrier in English;
  • Amerikaanse blauwe kiekendief in Caribbean Dutch;
  • Busard d’Amériquebusard des maraisbusard des roseaux, and Busard Saint-Martin d’Amérique in Caribbean French;
  • Malfini savann in Caribbean creole;
  • Tartaranhão-azulado in Brazilian Portuguese.

They most accurately carry the scientific name Circus hudsonius. Twenty-first century research based on scientific breakthroughs and technological advances frees them from previous subordination in 1766 by Carl Linnaeus (May 23, 1707 – January 10, 1778) to the subspecies C.c. hudsonius within the originally one-specied genus Circus cyaneus.

 

young male Circus cyaneus:

Despite physical similarities between C. cyaneus and C. hudsonius, distinctive differences, distinguishing them as separate species, are evinced at the molecular level.
Akcja Bałtycka (Operation Baltic), University of Gdańsk
Akcja Bałtycka (Operation Baltic), University of Gdańsk

 

The scientific name acknowledges in the genus, not performability in a circus, but low-circling flight patterns (from the ancient Greek κρίκος [krikos, “ring”]) and -- in the species – location of the first specimen known to European collection (from the Latin for “relating to the Hudson [River]”). The previous species name cyaneus attributes to blue-grey coloring predominance in identification. Adult females actually convey brown-reds above, with brown-streaked buffing below and white-ringed upper tails. Adult males actually display grey breasts and uppers, with black-tipped wings and white-rumped tails. From a distance, both genders may be confused with:

  • Cooper’s hawks (Accipiter cooperii);
  • Northern goshawks (Accipiter gentilis);
  • Rough-legged hawks (Buteo lagopus).

The marsh hawk’s back-and-forth, low-ground coursing serves as sure-fire identification. 

 

Circus hudsonius:

Differences at the molecular level, publicized in the 21st century, have confirmed for the ring-tail marsh hawk its transfer from subspecies (Circus cyaneus hudsonius) to its own species, Circus hudsonius.
Northern harrier (marsh hawk)
Northern harrier (marsh hawk)

 

The term ring-tail applies only to:

  • Female and male juveniles, whose eyes respectively are dark chocolate-brown and pale green-yellow;
  • Female adults, whose eyes are adult male-like in lemony yellowness.

The phrase grey ghost applies only to adult males because of their spectral colors. But ghostliness characterizes all marsh harriers because of owl-like facial discs for detecting such vegetation-camouflaged prey as:

  • Cotton rats;
  • Field voles;
  • Ground squirrels.  

 

Grey ghost: male's spectral coloring

Northern harrier
Northern harrier

 

Small mammals comprise 95% of marsh hawk diets. Grey ghosts and ring-tails also consider:

  • Amphibians (especially frogs);
  • Insects (especially cicadas, crickets, grasshoppers, katydids, locusts);
  • Reptiles.

The grey ghost’s diet additionally contains:

  • Ducks;
  • Gamebirds;
  • Passerines (especially larks, pipits, sparrows);
  • Rabbits;
  • Shorebirds;
  • Waterfowl.

Excepting food for newborns, everything gets eaten on the ground.

 

Light ash-grey male rests while umber-brown female consumes prey on ground:

"When satiated with food, the Marsh Hawk may be seen perched on a fence-stake for more than an hour, standing motionless....until digestion was accomplished." (J.J. Audubon, p. 109)
illustrations by John James Audubon (April 26, 1785 - January 27, 1851
illustrations by John James Audubon (April 26, 1785 - January 27, 1851

 

Grey ghosts are the only polygynous hawks. Each male, 3 years and older, begins mating with 3 - 5 females -- aged 2 years and older -- between March and June. Within alder, cattail, and willow groves, mothers-to-be build in 1 - 2 weeks ground-level nests measuring:

  • 8 - 10 inches (20.32 - 25.4 centimeters) wide by 2 - 4 inches (5.08 - 10.16 centimeters) deep interiorly;
  • 16 - 24 inches (40.64 - 60.96 centimeters) wide by 4-8 inches (10.16 - 20.32 centimeters) high exteriorly.

The grass-, rush- and sedge-lined nests contain cattail, reed, and willow parts. Within 24 - 39 days, 2 to 10 unmarked blue-white eggs, sized 1.9 inches (47 millimeters) by 1.4 inches (36 millimeters), hatch if they are not devoured by:

  • Badgers;
  • Crows, owls, ravens;
  • Raccoons;
  • Red foxes;
  • Skunks.

Newborns have 36 days to fledge. 

 

closeup of Great Horned Owl (Bubo virginianus):

tenacious predator of Circus hudsonius fledglings
John Heinz National Wildlife Refuge at Tinicum, southeastern Pennsylvania
John Heinz National Wildlife Refuge at Tinicum, southeastern Pennsylvania

 

Everything about marsh harriers acknowledges length. Fledglings that survive their most virulent predator, the great horned owl (Bubo virginianus), become medium-sized raptors showcasing:

  • Long, narrow faces with down-turned beaks, ruffled sound-directing feathers, and tan eyebrows;
  • Long, slender bodies with long, rounded tails and long, V-held wings;
  • Long, unfeathered, yellow legs with long, sharp talons on anisodactylic (3 toes forward, 1 back) feet.

Adult harriers exhibit the longest tail and wing lengths relative to body size of all North American raptors. They realize:

  • Body lengths of 16 - 24 inches (40.64 - 60.96 centimeters);
  • Tail lengths of 7.6 - 10.2 inches (19.30 - 25.91 centimeters);
  • Weights of 10 - 14 ounces (283.49 - 396.89 grams) in males and 14 - 26 ounces (396.89 - 737.09 grams) in females;
  • Wingspans of 38 - 48 inches (96.52 - 121.92 centimeters).

 

Circus cyaneus males share with their Circus hudsonius male relatives impressive wing spans and spectral coloring.

"Busard Saint-Martin / Hen Harrier Circus cyaneus, male. France."
"Busard Saint-Martin / Hen Harrier Circus cyaneus, male. France."

 

Except for dropping food for mothers and nestlings, male harriers absent themselves from family life. They are solitary other than:

  • Competing in diving, rolling, somersaulting, swooping courtship flights;
  • Foraging in groups of tens;
  • Migrating in high-flying flocks, August to November and March to May.

They assert claims to territories, each of which measures about 1 square mile (2.59 square kilometers). They can sustain daily flights of 100+ miles (160.93 kilometers). They communicate by way of such calls as:

  • Chek-chek-chek;
  • Chuk-uk-uk-uk during courtship.

They heed such female-emitted calls as:

  • Chit-it-it-it-it-et-it to sound predatory and territorial alarms;
  • Piih-eh to whistle “thanks” for food drops.

Females and males may live 8 years in the wild and 16 years in captivity.

 

Ring-tailed marsh hawk, also known as Northern harrier: a ruler of the skies, earth, and waters

Brazoria National Wildlife Refuge, Gulf Coast, southeastern Texas
Brazoria National Wildlife Refuge, Gulf Coast, southeastern Texas

Conclusion: Millennia of existence, from fossil record onward to 21st century sustainability shocks

 

The oldest known marsh hawk fossils date back 11,000 - 40,000 years in Mexico. Harriers therefore emerge as adaptable survivors since Mesoamerica’s role as cultural and environmental conduit continues into the twenty-first century. Harrier hawks favor high-profile existences in their Western Hemisphere habitat choices of:

  • Bogs, marshes, moorlands, swamps, wetlands;
  • Grasslands;
  • Prairies;
  • Shrublands;
  • Thicketlands;
  • Tundra.

They closely hunt open-country prey by flying near to the ground. They impress cultivators, farmers and growers with:

  • Abstention from poultry;
  • Pursuit of crop-damaging insects and mammals, quail-eating predators, and reptilian pests.

Marsh hawks still keep harrier population levels sustainable despite agro-industry’s heavy pesticide usage of 1950 - 1990. May sustainability survive the twenty-first century’s ironically harrier habitat-damaging endeavors of:

  • Agro-industrialists;
  • Wetland diversifiers;
  • Wind energy proponents. 

 

Acknowledgment

 

My special thanks to:

  • Talented artists and photographers/concerned organizations who make their fine images available on the Internet;
  • Virginia Polytechnic Institute and State University for superior on-campus and on-line resources.

 

Marsh hawk's economic value: "...unquestionably one of the most beneficial...its presence and increase should be encouraged in every way possible..." (Albert Kenrick Fisher, quoted by Collins Thurber, "The Marsh Hawk," p. 202)

"In South Carolina and other rice-growing states this Hawk drives away the reed birds or bobolinks, thus, in a measure, helping to protect the rice fields from the deprivations of this omnivorous bird." (C. Thurber, p. 202)
"About 1/4 Life-size" ~ William Kerr Higley, ed., Birds and Nature in Natural Colors (1905), Vol. I, opp. p. 201
"About 1/4 Life-size" ~ William Kerr Higley, ed., Birds and Nature in Natural Colors (1905), Vol. I, opp. p. 201

Sources Consulted

 

"American Harrier (Circus hudsonius) (Linnaeus, 1766)." Avibase the world bird database managed by D. Lepage. Retrieved on February 6, 2014.

  • Available at: http://avibase.bsc-eoc.org/species.jsp?avibaseid=A091D50AA92D949C

Audubon, John James. The Birds of America, From Drawings Made in the United States and Their Territories. Volume I. New York: J.J. Audubon; Philadelphia: J.B. Chevalier, 1840. Retrieved on February 6, 2014.

  • Available via Biodiversity Heritage Library at: http://biodiversitylibrary.org/page/40383032

Baicich P.; C. Harrison. (1997). A Guide to the Nests, Eggs, and Nestlings of North American Birds. New York City, NY: Academic Press.

BirdLife International. (2013). "Circus cyaneus." IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved on February 6, 2014.

  • Available at: http://www.iucnredlist.org/details/22695384/0

BirdLife International. (2014). "Species factsheet: Circus cyaneus." Threatened Birds of the World. Retrieved on February 6, 2014.

  • Available at: http://www.birdlife.org/datazone/speciesfactsheet.php?id=3407

Hamerstrom, Frances. 1986. Harrier, Hawk of the Marshes: The Hawk That Is Ruled by a Mouse. Washington DC: Smithsonian Institution Press, 1986. 

"The Harrier Hawk." The Wonder of Birds. Retrieved on February 6, 2014.

  • Available at: http://www.thewonderofbirds.com/harrier-hawk/

"Hen harrier Circus cyaneus." In: Grzimek's Animal Life Encyclopedia, 2nd edition. Volume 8, Birds I, edited by M. Hutchins, J.A. Jackson, W.J. Bock, and D. Olendorf. Farmington Hills, MI: Gale Group, 2002.

"Hen or American Harrier." (Circus [cyaneus or hudsonius]) (Linnaeus, 1766)." Avibase the world bird database managed by D. Lepage. Retrieved on February 6, 2014.

  • Available at: http://avibase.bsc-eoc.org/species.jsp?avibaseid=82745BAA8BE0E1BE
Limas, B. 2001. "Circus cyaneus" (On-line), Animal Diversity Web

Limas B. (2001). "Circus cyaneus (On-line)." Animal Diversity Web. University of Michigan Museum of Zoology. Retrieved on February 6, 2014.

Limas, B. 2001. "Circus cyaneus" (On-line), Animal Diversity WebRetrieved on January 29, 2014.
  • Available at: http://animaldiversity.ummz.umich.edu/site/accounts/information/Circus_cyaneus.html

Merrill J. (1998). "Marsh Hawk." Great Salt Lake Food Web. Retrieved on February 6, 2014. 

  • Available at: http://people.westminstercollege.edu/faculty/tharrison/gslfood/studentpages/hawk.htm

"Northern harrier (Circus cyaneus)." ARKive. Retrieved on February 6, 2014.

  • Available at: http://www.arkive.org/northern-harrier/circus-cyaneus/#src=portletV3api

"Northern Harrier (Circus cyaneus). Wildlife Fact Sheets. Texas Parks and Wildlife Department. Retrieved on February 6, 2014.

  • Available at: http://www.tpwd.state.tx.us/huntwild/wild/species/harrier/

"Northern Harrier Circus hudsonius." The Peregrine Fund. Global Raptor Information Network, 2014. Retrieved on February 6, 2014.

  • Available at: http://www.globalraptors.org/grin/SpeciesResults.asp?specID=8366

"Northern Harrier, Life History." All About Birds. Cornell Lab of Ornithology. Retrieved on February 6, 2014.

  • Available at: http://www.allaboutbirds.org/guide/northern_harrier/lifehistory

"Northern Harriers." Avian Web. Retrieved on February 6, 2014.

  • Available at: http://www.avianweb.com/northernharriers.html

"Raptors Order Accipitriformes: Kites, Hawks and Eagles Family Accipitridae. In: IOC World Bird List, version 4.1, edited by F. Gill and D. Donsker. International Ornithologists' Union, 2014. Retrieved on February 6, 2014.

  • Available at: http://www.worldbirdnames.org/n-raptors.html

Thurber, Collins. "The Marsh Hawk (Circus hudsonius)." Pages 201-202. In: William Kerr Higley, ed., Birds and Nature in Natural Colors. Forty Illustrations by Color Photography. A Guide in the Study of Nature. Volume I. Chicago IL: A.W. Mumford, 1905. Retrieved on February 6, 2014.

  • Available via Biodiversity Heritage Library at: http://biodiversitylibrary.org/page/36105841

Warren, B.H. (Benjamin Harry). Report on the Birds of Pennsylvania. With Special Reference to the Food-Habits, Based on Over Three Thousand Stomach Examinations. Harrisburg PA: Edwin K. Meyers, 1888. Retrieved on February 6, 2014.

  • Available via Biodiversity Heritage Library at: http://biodiversitylibrary.org/page/14463745

 

Ring-tail marsh hawk: transitioning from landing to perching

Morro Bay, Central Coast, California
Morro Bay, Central Coast, California
the end which is also the beginning
the end which is also the beginning

Northern Harrier male in flight, January, in Connecticut: photo by Jim Zipp

10x14 Photo Puzzle with 252 pieces. Packed in black cardboard box, 5 5/8 x 7 5/8 x 1 1/5. Puzzle image 5x7 affixed to box top.
Photo Jigsaw Puzzle of Northern Harrier male

immature male Northern Harrier in flight, January, in Connecticut: photo by Jim Zipp

10x14 Photo Puzzle with 252 pieces. Packed in black cardboard box, 5 5/8 x 7 5/8 x 1 1/5. Puzzle image 5x7 affixed to box top.
Photo Jigsaw Puzzle of Northern Harrier immature male

female Northern Harrier in flight while hunting, Farmington Bay Waterfowl Management Area, Great Salt Lake's eastern shore, Utah: photo by James Hager

10x14 Photo Puzzle with 252 pieces. Packed in black cardboard box, 5 5/8 x 7 5/8 x 1 1/5. Puzzle image 5x7 affixed to box top.
Photo Jigsaw Puzzle of Female northern harrier (Circus cyaneus) in ...

Northern Harrier chicks at nest site on ground, July, in Wyoming: photo by Jim Zipp

10x14 Photo Puzzle with 252 pieces. Packed in black cardboard box, 5 5/8 x 7 5/8 x 1 1/5. Puzzle image 5x7 affixed to box top.
Photo Jigsaw Puzzle of Hen / Northern Harrier - chicks
female Northern Harrier in flight while hunting, Farmington Bay Waterfowl Management Area, Great Salt Lake eastern shore, Utah: photo by James Hager
Female Northern Harrier (Circus Cyaneus) in Flight While Hunting, Farmington Bay, Utah, USA

Me and my purrfectly purrfect Maine coon kittycat, Augusta "Gusty" Sunshine

Gusty and I thank you for reading this article and hope that our product selection interests you; Gusty Gus receives favorite treats from my commissions.
DerdriuMarriner, All Rights Reserved
DerdriuMarriner, All Rights Reserved
Updated: 08/20/2014, DerdriuMarriner
 
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DerdriuMarriner on 02/10/2014

Mira, In kleptoparasitism, one predator steals the prey that has been captured by another predator. Ringtail marsh hawks and short-eared owls have a history of buzzing around one another about prey, and usually the ringtails win: they let short-eared owls do all the work of capturing prey, and then ringtails pester the owls into abandoning or dropping their prey.
It's one of those games that predators prey -- I mean: play. :-)

Mira on 02/10/2014

So why are they called kleptoparasitic again? One of them lays the pray somewhere and the other steals it?

DerdriuMarriner on 02/09/2014

VioletteRose, Me, too, I agree that ring-tail marsh hawks look great.
Nature is filled with beautiful, interesting creatures and plants, so I enjoy sharing my favorites. Ringtails are special favorites for me.

VioletteRose on 02/09/2014

They look great! I really enjoy reading your articles on many different animals and birds, they are very informative. Thank you.

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