[323.] NYCTICORAX OBSCURUS, Bp.
(DARK NIGHT-HERON.)
Nycticorax obscurus, Scl. et Salv. Nomencl. p. 126; Durnford, Ibis, 1878, p. 03 (Buenos Ayres), et p. 399 (Patagonia); Gibson, Ibis, 1880, p. 158 (Buenos Ayres). Ardea gardeni, Burm. La-Plata Reise, ii. p. 508 (Paraná). Nycticorax gardeni, White, P. Z. S. 1882, p. 624 (Buenos Ayres and Salta); Barrows, Auk, 1884, p. 271 (Entrerios).
Description.—Above cinereous; front white; head, nape, and scapulars greenish black; elongated nuchal plumes white: beneath paler, whitish on throat and middle of belly; bill black; feet flesh-colour: whole length 26·0 inches, wing 12·0, tail 4·8, tarsus 3·2. Female similar.
Hab. Southern half of South America.
In the Argentine Republic the Night-Heron lives in communities, and passes the hours of daylight perched inactive on large trees or in marshes on the rushes, and when disturbed by day they rise up with heavy flappings and a loud qua-qua cry. At sunset they quit their retreat, to ascend a stream or seek some distant feeding-ground, and travel with a slow flight, bird succeeding bird at long intervals, and uttering their far-sounding, hoarse, barking night-cry.
Where the flock lives amongst the rushes, in places where there are no trees, the birds, by breaking down the rushes across each other, construct false nests or platforms to perch on. These platforms are placed close together, usually where the rushes are thickest, and serve the birds for an entire winter.
The breeding-habits of the Night-Heron have already been described in the account of the Ardea egretta.
In the Falkland Islands, where Captain Abbott discovered a heronry (cf. Ibis, 1861, p. 157), their breeding-habits are the same as on the pampas.