(1794) Circus aeruginosus aeruginosus.
THE MARSH -HARRIER .
Falco aeruginosus Linn., Syst. Nat., 10th ed. i, p. 91 (1758) (Sweden). Circus aeruginosus. Blanf. & Oates, iii, p. 387.
Vernacular names. Kutar, Kulesir (Hind.); Mat-chil (Beng.) ; Safed-sira, Tika Bauri (Beng. Mahom.) ; Kurala goya (Cing.) ; Prandu (Tam., Ceylon).
Description. Head and neck, breast and coverts along forearm buff, pale rufous or rufous-buff with dark brown central streaks ; back and scapulars dark brown; upper tail-coverts white with rufous-grey bands and mottlings; tail silver-grey, tipped white and with white edges to the inner webs of the outer feathers, where also there are indications of rufous-brown bars; wing-coverts dark brown, with more or less rufous tips to the feathers ; outer greater coverts brown with broad grey tips and edges; primary coverts and inner quills silver-grey; first six primaries blackish, mottled with white on the bases ; second to fifth primary notched; abdomen, posterior flanks, vent and under tail-coverts pale to dark rufous, with darker central streaks, the colour of the breast and abdomen grading into one another; under wing-coverts white ; axillaries like the breast.
Colours of soft parts. Iris gold en-yellow, duller in females and brownish in the young; bill black; the base, gonys and cere yellow to dull greenish-yellow ; legs and feet yellow to orange-yellow.
Measurements. , wing 385 to 405 mm.; tail 234 to 245 mm.; tarsus 80 to 85 mm.; culmen 28 to 30 mm. , wing 390 to 430 mm.; tail 238 to 258 mm.; tarsus 85 to 90 mm.; culmen 28 to 31 mm.
Female. Forehead to nape, chin, throat and sometimes upper breast buff, the crown lightly streaked with dark brown; remainder of plumage dark brown, the back and lesser wing-coverts generally having a little rufous streaking; the wing-coverts and quills nearly always have paler rufous tips and there are sometimes some fulvous patches and mottling on the lower breast.
Young birds are wholly brown but the nuchal patch always and the anterior crown generally are buffy-white to pale rufous, with some dark brown shaft-lines and streaks.
Distribution, Europe to Western Siberia, extending in Winter to the whole of India, Ceylon, Burma and the Malay Peninsula. The North-African bird has been separated as C. ae. harterti. It has the upper tail-coverts pure white.
Nidification. The Marsh-Harrier breeds from March to May in the South and from April to early June in the Northern areas of its range. The nest is nearly always placed in, or alongside, marshes and swamps and is a bigger, better-put-together affair than most Harriers' nests, consisting of a mass of reeds and rushes well-lined with dry grass. The eggs number four to six and are nearly always unspotted white with a bluish tint when fresh. Marked eggs are very exceptional. One hundred and six eggs average 49.5 x 38.6 mm. : maxima 54.6 x 39.1 and 51.0 X 42.1 mm.; minima 45.0 X 37.3 and 46.3 x 35.6 mm.
Habits. The Marsh-Harrier is essentially a bird of water-logged lands but with this exception its habits are much the same as those of other Harriers. It is a bigger, more powerful bird than the others and accordingly sometimes tackles bigger prey and it has been known to carry away Teal when wounded. It is said to be a desperate egg-thief and to do immense mischief to colonies of breeding Terns, stealing both eggs and young. This Harrier has been suspected of breeding in India and eggs were brought to me by a Mikir said to be of this bird but there is no actual proof so far that it is more than a very early visitor in September and takes its departure very late.