the ocean floor, to an altitude of above sea level at Bandeera Peak, at the north-western edge. The volcano is topped by a caldera, 700–900 meters in diameter and about deep. There are three smaller cones to the north, northwest and south of the main crater. The volcano has not erupted in historical times, but by radiocarbon dating, eruptions occurred in 540 AD and 870 AD, with a potential dating error of around 100 years. These eruptions involved pyroclastic flows and had a VEI of 4. Any claims of historical eruptions are inaccurate, though uncertain eruptions have occurred as late as 1887. Within the main crater and on the western slopes are a number of active fumaroles. The island has extremely steep slopes on its eastern side which are prone to landslides. The western slope has deep canyons as the result of erosion. The shoreline is dominated by steep cliffs of up to on the eastern shore. Vegetation on the island's west side includes swordgrass (Miscanthus floridulus). The south-east side is a steep slope of bare lava. Coconut palms (Cocos nucifera), grow on the gradual slopes. There are deep valleys with caves, and there are fresh water springs on the northern part of the west coast. 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, Saipan reed warblers and Micronesian starlings. Demographics As of 1980 the population of Alamagan was 36. See also List of stratovolcanoes 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 Pascal Horst Lehne and Christoph Gäbler: Über die Marianen. Lehne-Verlag, Wohldorf in Germany 1972. and Alamagan Marianas Archipelago Coral Reef Ecosystems Monitoring Program Notes Former German colonies Islands of the Northern Mariana Islands Active volcanoes Volcanoes of the Northern Mariana Islands Stratovolcanoes of the United States Calderas of Oceania Uninhabited islands of the Northern Mariana Islands Important Bird Areas of the Northern Mariana Islands Holocene stratovolcanoes