Current view: Text account
Site description (2007 baseline):
Site location and context
The proposed Northern Saipan IBA is located on the island of Saipan. The proposed IBA
contains two areas that are currently protected by CNMI law as conservation areas: Bird
Island and land up to and including the Saipan Upland Mitigation Bank. The IBA also
includes the Marpi area that is not protected. Bird Island has small populations of
terrestrial and sea birds. The Mitigation Bank is an area that has specifically been set
aside for the protection of Nightingale Reed Warblers and as mitigation for development
in other locations that disturbs warblers.
In 1982, Engbring et al. (1986) found the Golden White-Eye to be well-distributed throughout Saipan. They also found that the bird was well adapted to residential and agriforest areas and apparently did well in all vegetation types. It was restricted to Saipan and Aguiguan only. Stinson and Stinson (1994) also found the bird in a variety of forest and semi-open areas. Craig (1996) repeated the methods of Engbring et al. (1986), comparing areas of limestone forest with disturbed sites. He found the Micronesian Megapode, Mariana Fruit-Dove, and Golden White Eye to be more common in limestone forest than in disturbed habitats. The White-throated Ground-Dove, Rufous Fantail, Micronesian Starling, Micronesian Honeyeater, and Bridled White Eye were all found in both native forest and disturbed habitats. The Nightingale Reed Warbler was observed more often in disturbed habitats than in limestone forest. The Mariana Swiftlet was not systematically surveyed by Craig (1996) but he did observe the birds in the more mountainous areas. After surveys in 2004 and 2005, Hess and Pratt (2006) wrote that most native birds on Saipan, including the Golden White-Eye, Nightingale Reed Warbler, Mariana Swiftlet, and Micronesian Megapode, are found in the northern part of Saipan. Micronesian Megapodes may be found throughout Saipan, but appear to be concentrated in the north. These species were found in existing conservation areas in the north of Saipan and in some unprotected lands, also in the north. This northern region corresponds with the Suicide region surveyed by Engbring et al. (1986), where, in 1982, the only Micronesian Megapodes in Saipan were observed. Stinson et al. (1993) found the Mariana Common Moorhen in Lake Susupe and in other small wetlands around the island. Tanaka and Haig (2004) found Mariana Common Moorhens at a number of seasonal and permanent wetlands on Saipan. Hess and Pratt (2006) found Mariana Common Moorhens and Nightingale Reed Warblers residing in wetlands in wetlands in the American Memorial Park in the Garapan region. Reichel (1991) reported over 500 pairs of breeding seabirds on Saipan, including 300 pairs of Brown Noddies and 200 pairs of White Terns.
Pressure/threats to key biodiversity
There have been over 60 confirmed records of the Brown Treesnake on Saipan (Campbell, 2004), which may be already established on the island. Craig (1999) wrote that the Brown Treesnake had successfully been established in Saipan in the 1990s, posing an immediate threat to all Golden White-Eyes on Saipan and “dooming” them to extinction. However, the current status of the Brown Treesnake on Saipan is unclear, although many biologists believe that an initial population is in the initial stages of establishment (Wiles, pers. comm.). Saipan is the administrative and commercial center for the CNMI, and has been heavily impacted by man. Further introduced species and additional forest degradation or loss may pose additional threats. Rats and monitor lizards are current threats.
The proposed IBA contains two areas that are currently protected by CNMI law as conservation areas: Bird Island and land up to and including the Saipan Upland Mitigation Bank. Bird Island has small populations of terrestrial and sea birds. The Mitigation Bank is an area that has specifically been set aside for the protection of Nightingale Reed Warblers and as mitigation for development in other locations that disturbs warblers.
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Northern Saipan (Northern Mariana Islands (to USA)). Downloaded from
https://datazone.birdlife.org/site/factsheet/northern-saipan-iba-northern-mariana-islands-(to-usa) on 23/11/2024.
