Northern Saipan

Country/territory: Northern Mariana Islands (to USA)

IBA Criteria met: A1, A2 (2007)
For more information about IBA criteria please click here

Area: 731 ha

Most recent IBA monitoring assessment
Year of assessment Threat score (pressure) Condition score (state) Action score (response)
2007 high not assessed not assessed
For more information about IBA monitoring please click here

Site description
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.

Key biodiversity
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.

Recommended citation
BirdLife International (2023) Important Bird Areas factsheet: Northern Saipan. Downloaded from on 07/02/2023.