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Western Marsh Harrier - BirdForum Opus

(Redirected from Circus aeruginosus)

Alternative name: Eurasian Marsh Harrier

Nominate subspecies : Male
Photo © by Alok Tewari
Keoladeo National Park, India, December-2016
Circus aeruginosus


Nominate subspecies : Female
Photo © by Alok Tewari
Gurgaon, Haryana, India, March-2015

43–55 cm (17-21¾ in)

  • Yellowish-white head and breast
  • Black wing tips
  • rest of wing grey and brown
  • Bluish-grey tail
  • Brown belly


  • Brown overall plumage
  • Cream crown, throat and leading edge wing

Similar Species

African Marsh Harrier and Eastern Marsh Harrier are the closest.


Nominate subspecies
Photo © by stejon
Meldorfer Bay, Germany, May 2003

Eurasia and north Africa. Widely distributed in the Western Palearctic region from Spain and northwest Africa, east across Russia to Central Asia and north to Scandinavia. It is extremely patchy across most of this area but there are small breeding populations in most countries of mainland Europe, as well as southern Britain, Sweden and Finland. Also breeds in Morocco, northern Algeria and Tunisia, and parts of Turkey and Iraq. Has begun a major expansion in northern Europe in recent decades after declining through persecution and loss of habitat. However, the species is still under pressure in parts of the Mediterranean, eastern Europe and the Middle East. Increasing in Britain with about 200 pairs present in 2000 from southeast England north to central Scotland.

Northern and eastern populations are migratory and winter in Africa and around the Mediterranean. Birds from Britain, France and Spain, and those from the eastern Mediterranean are resident or dispersive. A broad-front migrant but still appears at migration watchpoints in some numbers, particularly Gibraltar and Borçka. Wintering in central and eastern Europe is rare but does occur at Lake Neusiedl in Austria. Recorded as a vagrant in Iceland and the Faroes, Madeira and on the Azores.


Nominate subspecies : Immature male
Photo © by Alok Tewari
Jamnagar, Coastal Gujarat, India, December-2017

A number of current species have in the past been seen as subspecies of Western Marsh Harrier: Eastern Marsh Harrier, Swamp Harrier, Reunion Harrier, Malagasy Harrier, African Marsh Harrier.


There are 2 subspecies[1]:

  • C. a. aeruginosus:
  • C. a. harterti:


Breeds in reedbeds or other dense vegetation beside lakes, ponds and rivers or in marshes. Rarely, may nest in cornfields or heather. Hunts over water, reedbeds and adjacent farmland.



They prey on a wide variety of marsh birds and mammals. The diet includes birds' eggs, snakes, lizards, frogs, fish and insects.


They generally nest in reed beds.



  1. Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2017. The eBird/Clements checklist of birds of the world: v2017, with updates to August 2017. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
  2. mlahanas.de Cyprus
  3. Handbook of the Birds of the World Alive (retrieved Feb 2018)
  4. Collins Bird Guide App

Recommended Citation

External Links

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