Gray-backed Tern
Onychoprion lunatus
A medium-sized tern of the tropical Pacific. Similar to Sooty Tern, but the back is gray (not black) and the white patch on the forehead extends behind the eye. Note deeply forked tail. Nests on the ground and occasionally on ledges on tropical islands. Rarely seen from shore.
Identification
A close relative of the bridled and sooty terns (with which it is sometimes confused), the spectacled tern is less common than the other members of its genus and it has been studied less. The three species, along with the Aleutian tern were recently split into a new genus Onychoprion from Sterna (Bridge et al., 2005). They resemble the sooty tern but with a grey back instead of a black one. Their breast and underparts are white, and they have a black eye line from the bill to the back of the head.
Taxonomy
- Scientific name
- Onychoprion lunatus
- Authority
- (Peale, 1849)
- Order
- Charadriiformes
- Family
- Laridae
- Genus
- Onychoprion
Range and habitat
The spectacled tern breeds on islands of the tropical Pacific Ocean. At the northern end of its distribution it nests in the Northwestern Hawaiian Islands (with the largest population being Lisianski Island) and two small islets off Oahu, in the east as far as the Tuamotu Islands, with other colonies in the Society Islands, the Line Islands, Phoenix Islands, Mariana Islands and American Samoa. There are unconfirmed reports of breeding as far south as Fiji, and as far east as Easter Island. Little is known about the populations outside of Hawaii. Outside of the breeding season the species is partly migratory, with birds from the Hawaiian Islands flying south. It is thought that birds in other parts of the Pacific are also migratory, and will disperse as far as Papua New Guinea, the Philippines, and Easter Island.
- Breeding range
- PO : sw to c tropical Pacific Ocean: n Mariana, Phoenix, Line, Tuamotu, Marquesas, American Samoa, Northwestern Hawaiian Is., islets off Kauai and Oahu (main Hawaiian Is.) and Johnston Atoll (s of Hawaii)
- Non-breeding range
- to ne Melanesia in sw, and far e Polynesia in e
- Migration
- Resident species
Conservation
- Population trend
- declining
Photos
Distribution
Bird Calls
Other Birds
Giant Nuthatch
Sitta magna
The largest nuthatch in the world, about the size of a bulbul. Coloration similar to many other nuthatches: gray above and white below, with a thick black line through the eye. Picky in its habitat preferences and as a result generally uncommon or absent through much of its range; requires extensive stands of mature tall pines in foothills and montane regions. Can be quite loud, giving a hoarse chatter reminiscent of a corvid; also gives a clipped fluty whistle.
White-crested Helmetshrike
Prionops plumatus
A sociable, cartoon-like, black-and-white helmetshrike with a grayish crest and a piercing yellow eye and eye-wattle. Groups fly with a labored flight action, showing a conspicuous pied pattern. Close-knit parties of 5 to 10 birds forage restlessly in mixed- or single-species flocks in broadleaf woodland and arid savanna, looking for insects at middle and lower levels. Groups give strange ratcheting and ringing calls, including clicks and whistles.
Yellow-eyed Black-Flycatcher
Melaenornis ardesiacus
Slim, long-tailed, all-black flycatcher with a pale yellow eye. Found along the edge and in clearings within Albertine Rift montane forest. Single birds of pairs perch out on conspicuous perches, sometimes quite low. Calls include low chuckling notes and a high, thin whistle; the song is a whispy, complex mix of high-pitched notes. Distinguished from all similar black birds by its pale eye.
Start Your Bird Watching Journey
Identify a bird outdoors and keep the field guide close for your next observation.