Harmful algal blooms

An algal bloom is a rapid increase or accumulation in the population of algae in a water system. While most are innocuous, there are a small number of algae species that produce harmful toxins to humans and animals. This section includes articles related to general information about harmful algal blooms and some of their impacts. 

Source: Sound Science 2007.

Overview

Harmful algal blooms in the Salish Sea

Formerly known as “Red Tide”, harmful algal blooms are a health concern for both wildlife and humans. The following is a brief review of some of these algae and their effects.

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Due to the 'Red Tide' misnomer, blooms of red-colored algae, like this Noctiluca sp. (a dinoflagellate) seen here in Eastsound, Washington (July 2016), can cause undue public concern about harmful algal blooms. Photo: Jordan Cole

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