More widespread ecological changes, such as global warming, may also underlie the harmful blooms. Swimming against this tide of opinion are observations of many HAB problems that occur in pristine waters, such as the paralytic shellfish poisoning problems in Alaska or the Gulf of Maine. Some of these blooms develop in offshore waters, far from human pollution. To Anderson, this just demonstrates that many natural and artificial factors are feeding the expansion of toxic blooms. The simple fact is that more scientists, with more instruments, are paying attention, which conspires to make a large problem look even larger.
Algae feed the animals that make coral.