No one really knows why algae put so much effort into making poisons. Alexandrium makes saxitoxin, and causes PSP. Another algae called Pseudo-nitzschia produces domoic acid, the source of amnesiac shellfish poisoning.

Researchers with Southeast Alaska Tribal Ocean Research found high levels of Paralytic Shellfish Toxin in a population of mollusks at Auke Recreation Area in Juneau on Friday.