Montagu's Harrier, Circus pygargus

Montagu's Harrier male

Montagu's Harrier male, Austria, Mai 2011, © Markus Jais

Montagu's Harrier female

Montagu's Harrier female, Austria, Mai 2011, © Markus Jais

Names

English: Montagu's Harrier
Scientific: Circus pygargus
German: Wiesenweihe
Spanish: Aguilucho Cenizo
French: Busard cendré

Taxonomy and Subspecies

Mixed pairs with the Pallid Harrier are known [Mebs and Schmidt 2006]. No subspecies [GRIN 2013, Mebs & Schmidt 2006].

Size

Length: 43-47 cm
Wingspan: 105-130 cm
Weight: Males 227-305 g, Females 319-445 g

Maximum Age

16 years in the wild. [Mebs & Schmidt 2006]

Habitat

Breeds and hunts in open country like marshes, steppes, grasslands and today more and more on arable farm land. At the end of the 20th century between 40 and 70% of the European population bred in arable farm land [Trierweiler 2009].

Distribution

Patchily distributed over most of Europe. Does not breed in Ireland and only with a few pairs in Great Britain. In Scandinavia only in the south of Sweden and maybe a few pairs in Finland. Outside of Europe eastwards to Siberia

Migration

Migratory species. European birds spend the winter in Africa south of the Sahara. Adults leave the breeding areas often before the young.
Most birds leave Europe in August and September. Central European birds return mostly in April [Mebs & Schmidt 2006].
20 birds from Denmark, the Netherlands and Germany marked with satellite transmitters used the same route during spring and autumn migration. About 75% used a route via France and Spain, the other birds via Italy and Sardinia. Tracked birds from north-east Europe used loop migration, going south via Greece and Crete and flying north via Italy and Sardinia. It seems that migration routes and strategies differs for different population [Trierweiler 2009].

Breeding and Reproduction

Starts breeding with 1 or 2 years.
Nests are built on the ground in reed beds, grasslands, heathlands, young conifer plantation and arable crops [GRIN 2013]. In recent years, in some countries, more and more Montagu's Harriers nest in arable crops, for example in Bavaria.
The female lays 3-5 eggs and incubates them for 27-30 days. The young can fly after about 34 days. They already leave the nest a little earlier [Mebs & Schmidt 2006]. The parents provide food for the young for another 3-4 weeks [Mebs & Schmidt 2006].

Food and hunting

The most important prey are small mammals (especially Common Voles), small birds and large insects [Mebs & Schmidt 2006]. As vole populations often fluctuate the Montagu's Harrier kills more birds and other alternative prey when vole populations are low.
Lizards can be an important prey source in warmer regions [Mebs & Schmidt 2006]. During winter in Africa sedentary locusts are often taken when available but also small birds, beetles, mantis, small mammals or chameleons [Trierweiler 2009].
In France the Common Vole Microtus arvalis was shown to be between 60 and 90% of the consumed biomass [GRIN 2013]. Hunts like a typical harrier from a low flight above open country. Capable of catching small birds and insects in flight [Mebs & Schmidt 2006].

Population

[BirdLife 2004] gives a European population of 35,000 - 65,000 pairs. The populations are stable or increasing in most countries. Most pairs breed in eastern Europe. Russia has between 20,000 and 35,000 pairs and Belarus between 3,000 and 5,000 pairs. In western Europe larger populations exists in France (3,800 - 5,100). For Spain [BirdLife International 2004] estimates 2,500 - 10,000 pairs. [Mebs and Schmidt 2006] write of at least 4,926 pairs and [SEO 2007] gives between 4,000 and 5,000 pairs.

In Germany [Mebs and Schmidt 2006] give for the years 2001 - 2004 a population at between 377 and 428 pairs. In Bavaria the population has grown from only a few pairs at the beginning of the 1990ies to 153 in 2008 thanks to conservation programs.

Threats

Habitat destruction like the drainage of marshes and intensification of agriculture have reduced breeding numbers in many places. The species is capable of breeding in agricultural areas when enough food is available. But many nests are threatened by harvesting machines because harvesting of many crop fields is done during the breeding season.
Pesticide use, especially to kill locusts in some wintering quarters may also have a negative effect [Mebs & Schmidt 2006].
Illegal shooting during migration still occurs in some countries.
Use of insecticides including DDT to kill locusts in Africa are another threat for the birds during migration and in their wintering quarters.

Conservation

Illegal killing during migration must be stopped. Beside this, bird friendly agriculture should be promoted across Europe. That means less pesticides, paying farmers for wildlife friendly farming like setting aside some parts of their fields for a few years.
When harrier nests are found, farmers can leave some space around the nest which is not harvested. Farmers should be paid for the financial loss they have because of this measures.
Destroyed moorland should be restored.
Most of those measures above would also help many other species or birds including raptors like the Common Buzzard, Hen Harrier or the Eastern Imperial Eagle
Effective conservation of a long-distance migrant like the Montagu's Harrier also requires a detailed knowledge of migration routes and the location and structure of stopover sites and wintering quarters [Trierweiler 2009]. Satellite telemetry is currently the best way to learn more about the migration ecology of Montagu's Harriers.

Status IUCN/BirdLife

Least Concern (LC)

Status Global Raptor Information Network

Lower risk

Interviews about the Montagu's Harrier

Interview with Dominik Krupinski about the Montagu's Harrier in Poland

References

[BirdLife 2004] BirdLife International. 2004. Birds in Europe: population estimates, trends and conservation status. BirdLife Interntional. Cambridge, UK. (Montagu's Harrier species account available at: http://www.birdlife.org/datazone/species/BirdsInEuropeII/BiE2004Sp3411.pdf

[GRIN 2013] Global Raptor Information Network. 2009. Species account: Montagu's Harrier Circus pygargus. Downloaded from http://www.globalraptors.org on 12 Feb. 2013

[Mebs & Schmidt 2006] Mebs, Theodor & Schmidt, Daniel (2006). Die Greifvögel Europas, Nordafrikas und Vorderasiens. Kosmos Verlag.

[SEO 2007] SEO/BirdLife Spain, Juan M. Vaerla Simó 2007. Aves Amenazadas de España, Lynx Edicions

[Trierweiler 2009]. Trierweiler, Christiane. 2009. Weltreisende Wiesenweihen. Falke Journal.

Books

Forsman, Dick (1999). The Raptors of Europe and the Middle East A Handbook of Field Identification. Poyser

Mebs, Theodor & Schmidt, Daniel (2006). Die Greifvögel Europas, Nordafrikas und Vorderasiens. Kosmos Verlag.

Scott, Don (2008). Harriers - Journeys around the world. Tiercel Publishing. Wheathampstead

Simmons, Rob (2000). Harriers of the World. Oxford University Press. Oxford.

Websites

Dutch Montagu's Harrier Foundation

RSPB information about the Montagu's Harrier

GRIN species account for the Montagu's Harrier

BirdLife Species Factsheet for the Montagu's Harrier

Montagu's Harrier conservation in Bavaria

Montagu's Harrier conservation in the Rheinland (Germany)

Montagu's Harrier conservation in Oldenburger Land and Landkreis Diepholz (Germany)

busards.com - wing-tagged harriers resighting and recovery

pygargus.pl - Montagu's Harrier in Poland