shape, with a length of and a width of and an area of . The island is the summit of a stratovolcano which rises to an altitude of above sea level at its highest peak. The volcano is topped by a caldera, 750 meters in diameter, with an ash cone and two lava domes, which produced lava flows which reached the coast. No eruptions have been recorded in the historical period, although a swarm of volcano-tectonic earthquakes took place here in the summer of 2005. Landing on Sarigan is difficult because perpendicular cliffs surround much of the island. It has many ravines and valleys with dense tropical vegetation, particularly on the northern side of the island. The stratovolcano is at the southern end of the island, and there is a plateau north of it with an elevation of and a width of . To the north of the plateau are steep, vegetation-covered slopes, which go down to the sea. The island's north-western coast is the most habitable, climbing from an elevation of to in and having a lot of vegetation. Approximately south of Sarigan is the South Sarigan Seamount, a submarine volcano with several peaks, with a maximum height of 184 m below sea level. It briefly erupted in May 2010 producing a plume of water vapor about 12 km high. Important Bird Area The island has been recognised as an Important Bird Area (IBA) by BirdLife International because it supports populations of Micronesian megapodes, white-throated ground doves, Micronesian myzomelas and Micronesian starlings. Notes References Russell E. Brainard et al.: Coral reef ecosystem monitoring report of the Mariana Archipelago: 2003–2007. (=PIFSC Special Publication, SP-12-01) NOAA Fisheries, Pacific Islands Fisheries Science Center 2012 (Kapitel Alamagan (englisch, PDF, 12,2 MB)). Richard B. Moore, Frank A. Trusdell: Geologic map of Alamagan Volcano, northern Mariana Islands. United States Geological Survey 1993 (Download). External links Google Maps: Sarigan Pascal Horst Lehne and Christoph Gäbler: Über die Marianen. Lehne-Verlag, Wohldorf in Germany 1972. and Sarigan Stratovolcanoes of the United States Volcanoes of the Northern Mariana Islands Islands of the Northern Mariana Islands Former German colonies Uninhabited islands of the Northern Mariana Islands Important Bird Areas of the Northern Mariana Islands