Cyanotoxin which is why they are usually green or blue. Cyanobacteria are found almost everywhere; in oceans, lakes and rivers as well as on land. They flourish in Arctic and Antarctic lakes, hotsprings and wastewater treatment plants. They even inhabit the fur of polar bears, to which they impart a greenish tinge. Cyanobacteria produce potent toxins, but they also produce helpful bioactive compounds, including substances with antitumour, antiviral, anticancer, antibiotic and antifungal activity, UV protectants and specific inhibitors of enzymes. Cyanotoxins are often implicated in what are commonly called "red tides" or "harmful algal blooms". Lakes and oceans contain many single-celled
Great Lakes localized weather pattern, especially along the eastern shores of the lakes. Snow belts are found in Wisconsin, Michigan, Ohio, Pennsylvania, and New York, United States; and Ontario, Canada. The lakes also moderate seasonal temperatures to some degree, but not with as large an influence as do large oceans; they absorb heat and cool the air in summer, then slowly radiate that heat in autumn. They protect against frost during transitional weather, and keep the summertime temperatures cooler than further inland. This effect can be very localized and overridden by offshore wind patterns. This temperature buffering produces areas known as "fruit