Montagus Harrier

Montagus Harrier

Summary:

Profile Montagus Harrier     Literature page Montagus

[order] Falconiformes | [family] Accipitridae | [latin] Circus pygargus | [UK] Montagus Harrier | [FR] Busard cendré | [DE] Wiesenweihe | [ES] Aguilucho Cenizo | [IT] Albanella minore | [NL] Grauwe Kiekendief

Grauwe Kiekendief determination

copyright: youtube

Sexual dimorphism is particularly apparent in the plumage of this species. Adult males are characterized by their overall pale grey plumage contrasting with black wingtips. Compared with other harriers this species has characteristic black bands along the secondaries, both above and below the wing and rusty streaks on belly and flanks.
Adult females have a broadly similar plumage to that of Pallid and Hen Harriers. The underparts are mostly pale yellow-brown, the belly with longitudinal stripes and the wing coverts spotted. The upper parts are uniform dark brown except for the white upper tail coverts (“rump”), and the sightly paler central wing coverts.
The juvenile plumage resembles that of the female, but differs by the belly and under wing coverts which are not spotted, but uniformly red brown in colour.
A melanistic form occurs regularly in this species. In this form the male is much darker than usual, with a black head, brownish black above and grey underparts. The melanistic female is entirely chocolate brown except for grey flight feathers. Partially melanistic morphs can also be found.

This species can be found in a middle-latitude band of predominantly temperate climates, but also in Mediterranean, and boreal zones. Although it has been found nesting up to 1500 m, it is essentially a lowland species, and nests mostly in broad river valleys, plains, and levels bordering lakes and the sea. It can breed in wetlands, though these are often smaller and dryer than those used by the Marsh Harrier. It also utilizes heaths, dunes, moors, and can be found in the steppe. It adapts to shrublands in gorse or heather and to areas planted with young conifers.

When no other suitable habitat is available this harrier will nest in agricultural farmlands where it is vulnerable to early harvesting. Amongst these it chooses especially grasslands and cereal crops such as wheat, barley, oats and colza. In western Europe, up to 70 percent of the population breeds in artificial habitats.

The Montagu’s Harrier is possibly the most slender and elegant of its genus. Its body and wing form can, at times, cause it to be mistaken for a falcon. In flight it is the most buoyant of the Harriers and is reminiscent of the flight pattern of a tern – the slow glides interspersed with half a dozen wingbeats of such power that the bird lifts visibly.
Its hunting method is typical of its genus, quartering the land at low speed and low altitude, but with the ability to drop quickly and silently onto its prey once located.
Being a ground-nesting and roosting bird, this species, as well as suffering the persecution and indiscriminate shooting that has been the lot of many raptors over the last century or so, falls prey to the ravages of farm machinery (except where the farmer is aware of their presence and sufficiently interested to take some positive action). As a result of these problems, numbers of this species in much of Europe, and particularly in Britain, are only now recovering from disastrous losses., where it is almost as common as the very numerous resident Brahminy Kite Haliastur indus.
In its breeding areas, like other harriers, it spends a lot of the day on the wing, although probably less than many other harriers. It flies higher than other harriers, usually at ten to fifteen feet, and in a less buoyant and easy manner, though it has the harrier habit of gliding with wings held well above the level of the back. Although it appears, probably due to its larger size, to fly slower than other harriers its hunting speed has been estimated at 31-36 miles an hour, faster than most harriers.

This harrier inhabits steppes and open marshes of a large part of Eurasia, from the Iberian Peninsula and England to Mongolia. It breeds also in Morocco. Its winter quarters are in sub-Saharan Africa. The population of the European Union amounts to about 6100 breeding pairs, which represent about 20% of the total European population. This species is shows wide fluctuations, but since several decades seems to decrease. The population for the western Palearctic is estimated at 35,000-50,000 pairs. The global population is unknown and could be anything between 150,000 to 200,000 individuals(Birdlife International, 2004). This uncertainty is due to the fact that most of the world’s population is situated in Russia and former Soviet republics where it is not quantified.

Its prey is mostly small mammals, mainly rodents. It also takes, as the occasion demands, small birds – open country passerines and occasionally the young of ground-nesting birds. Small reptiles and large insects are also taken.


This species has a large range, with an estimated global Extent of Occurrence of 1,000,000-10,000,000 km2. It has a large global population estimated to be 100,000-1,000,000 individuals (Ferguson-Lees et al. 2001). Global population trends have not been quantified, 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). For these reasons, the species is evaluated as Least Concern. [conservation status from birdlife.org]


At 2 to 3 years of age, a pair is formed that sometimes lasts for the lifetime of the birds, although there is evidence not only of pair-changes in successive years, but also of occasional polygyny during a single season.
The courtship ritual involves the pair circling together to a great height, and playing a number of mid-air games including food-passes, diving, rolling and talon presentation.
The nest is constructed on the ground, in natural or cultivated vegetation, moorland, young forestry plantations or even sand-dunes. Building, mostly by the hen, takes about 4 days. The hen also takes the brunt (if not all) of the incubation duty, which lasts for about 30 days per egg – up to around 40 days for the full clutch of up to four or five eggs.
The young remain in the nest for about 3 weeks, when they start to crouch in surrounding vegetation, although still very much under the protection of the adults until they fledge at bout 42 days. Full independence is achieved about 14 days after fledging.

The Montagu’s Harrier is a long distance migrant. Birds from Eurasia spend the winter in sub-Saharan Africa, while those from the eastern part of the range migrate to the Indian subcontinent. In Europe, the first birds start to move at the beginning of August and most have left by mid-October. They travel over a broad front, crossing the Mediterranean at various points, and only a small number are observed at migration choke points. Western birds don’t go further south than the gulf of Guinea, but some eastern birds travel as far as South Africa. In Africa their diet is composed mostly of insects and birds, and it is possible that they follow locust swarms. Spring return peaks in April, and most birds have arrived by May though there is evidence that first-year juveniles spend their first summer in the winter quarters.

Specification

  1. Measurements
  2. spanwidth min.: 96 cm
  3. spanwidth max.: 116 cm
  4. size min.: 39 cm
  5. size max.: 50 cm
  6. Breeding
  7. incubation min.: 27 days
  8. incubation max.: 40 days
  9. fledging min.: 28 days
  10. fledging max.: 42 days
  11. broods 1
  12. eggs min.: 4
  13. eggs max.: 5
  14. Conservation Status
  15. Grauwe Kiekendief status Least Concern

Subspecies

  1. Polyboroides pygargus
  2. Circus pygargus
  3. EU w, c
Join the discussion