 In cultured non-nitrogen-fixing cyanobacteria, BMAA production increases in a nitrogen-depleted medium.BMAA has been found in aquatic organisms and in plants with cyanobacterial symbionts such as certain lichens, the floating fern "Azolla", the leaf petioles of the tropical flowering plant "Gunnera", cycads as well as in animals that eat the fleshy covering of cycad seeds, including flying foxes.High concentrations of BMAA are present in shark fins.