surrounded by ambient water of the same density with lower relative nutrient levels. The downstream of the Kuroshio Current receives large amounts of nutrients at rates of 100–280 kmol N*s-1. Nutrients are brought to the surface water from deeper layers where the Kuroshio Current flows over shallow areas and seamounts. This process occurs over the Okinawa Trough and the Tokara Strait. The Tokara Strait also has high cyclonic activity where the Kuroshio Current passes through. This in combination with the Coriolis effect causes intense upwelling along the continental shelf. This upwelling and nutrient transport into surface layers is essential for primary production because these vital nutrients would otherwise be inaccessible to phytoplankton which need to remain in upper layers where sunlight is available for them to perform photosynthesis. The constant transport of nutrient rich waters to regions with high levels of light therefore supports increased photosynthesis supporting the rest of the biologically diverse ecosystem associated with the Kuroshio current. Marine life The transportation of nutrients, heat and plankton by the Kuroshio Current and the current's transection of multiple different waterbodies gives way to high species richness in and adjacent to this current. In addition, the Kuroshio is classified as a biodiversity hotspot, meaning the waters circulating through the region are host to many different species, yet many of its resident organisms are at risk of becoming endangered or are already at the brink of extinction as a result of local and/or global human activity. Overfishing and overharvest are the primary risks for many of the threatened or endangered species here. Photoautotrophs Phytoplankton Phytoplankton are responsible for the aforementioned high rates of primary productivity within the current. Warm sea surface temperatures and low turbidity in the region lead to clearer waters which allows for deeper penetration of sunlight and an extension of the epipelagic zone. These particular characteristics, along with lower nutrient availability within the current, correspond well with the requirements of two specific cyanobacteria: Prochlorococcus and Synechococcus. Prochlorococcus is the dominate species of picophytoplankton within the Kuroshio Current and these two species may be responsible for as much as half of the fixation of in the entire Kuroshio Current photic zone. Further, there are substantial dust deposition events in this region due to Asian Dust Storms from the Gobi desert. During these events, dust clouds transport and deposit phosphate and trace metals which subsequently stimulate growth in both Prochlorococcus and