This Marine IBA is identified using seaward extensions around breeding colonies. It originates from the Japan Exclusive Economic Zone (EEZ) and falls within the Pacific, Northwest FAO ocean region. The site covers an area of 822 km2 and is 22 km away from the closet coastline. The depth ranges from 0 to 173 m, mean annual sea surface temperature falls between 18.27 and 18.46 °C and mean annual chlorophyll-a concentrations found to range between 0.5 and 1.17 mg/m3.
3 species trigger IBA criteria at this Marine IBA. Seaward extensions around breeding colony; Kanmurijima and Kutsujima islets include key near-colony areas for breeding populations of Streaked Shearwater (LC) , Swinhoe's Storm-petrel (NT) and Japanese Murrelet (VU).
BirdLife International (2020) Important Bird Areas factsheet: Kanmurijima and Kutsujima islets - Marine. Downloaded from http://www.birdlife.org on 26/02/2020.