[order] Charadriiformes | [family] Sternidae | [latin] Anous stolidus | [UK] Brown Noddy | [FR] Noddi brun | [DE] Noddi | [ES] Tinosa boba | [IT] Sterna stolida bruna | [NL] Noddy

Noddy determination

copyright: C. Kessler

Medium size, dark, brown bird. Adults have ashy-white forehead and crown sharply demarcated from black lores, merging evenly into grey nape. Long, narrow, wedged-shaped tail. Bill is black and stouter than the Black Noddy. Legs/feet dark brown. Weigh twice as much as black noddies. Young noddies have a more restricted white cap on forehead than adults.

Brown Noddies often breed in colonies with Sooty Terns, but they do not nest on the ground. This species exhibits breeding-site fidelity to an extraordinary degree. Apparently a pair returns to exactly the same nest year after year.

The Brown Noddy is a tropical seabird with a worldwide distribution, ranging from Hawaii to the Tuamotu Archipelago and Australia in the Pacific Ocean, from the Red Sea to the Seychelles and Australia in the Indian Ocean and in the Caribbean to Tristan da Cunha in the Atlantic Ocean.

Primarily feed by plunge diving. Feed offshore over schools of large predatory fish that drive small fry to surface. Feeds mainly on small fish (i.e., goatfish, flying fish) and squid. Often feeds in mixed species flocks.

This species has a large range, with an estimated global Extent of Occurrence of 10,000,000 kmē. The global population size has not been quantified, but it is believed to be large as the species is described as 'frequent' in at least parts of its range (Stotz et al. 1996). 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]

There is limited information on age at first breeding. Age of first breeding ranges between 3-6 years. Mates display characteristic "nodding" to one another. Courtship feeding is performed by the female begging from the male. The male may courtship feed the female several times a day. "Fish flights" occur, in which one bird transfers a fish to its partner.
The nest is a mass of dead vegetation placed from 1 to 4 m high in a bush or tree and usually lined with pebbles, shells, and bits of coral. Sometimes nesting occurs on the ground. Because a pair returns to the same nest each year, and continually adds to it, some nests are quite large. In the Dry Tortugas the species prefers to nest in bay cedars, but prickly-pair cactus and red mangrove are also used.
The incubation period of the Brown Noddy has been reported as 35 to 36 days, but this has been questioned because it is much longer than the incubation period of other terns. There is no doubt that the breeding season is prolonged. Brown Noddies lay a single white egg, which is sometimes tinted buff or pink. The egg is sparsely marked, mostly at the larger end, with reddish-brown and lilac spots. The birds sit very tightly while incubating and can be picked up off the nest by hand. This may explain the name noddy, which means stupid. The young leave the nest at about 20 days of age and first fly about 30 days after hatching. Both parents incubate.

Poorly known. Seldom seen on or close to shore away from breeding colony. Present most of year at most tropical colonies, but seasonally absent at subtropical ones. Disperses to sea after breeding. No known direct movement.