Water Management
What are algal blooms?
Most algae are safe and are a natural part of aquatic ecosystems. However, some algae can produce toxins that can be damaging to humans, domestic animals and livestock that drink or come in contact with the water, as well as to organisms living in water. These algae can be found in freshwater as well as brackish and marine waters.
Blue-green algae (also known as cyanobacteria) are the only group of algae to be toxic in freshwaters. They are microscopic bacteria living in water, and are capable of photosynthesising which is why they are often called algae. Though microscopic, when they form colonies and accumulate together they can become visible to the naked eye. Blue–green algae can produce potent liver and neurotoxins as well as skin irritants. However, not all blue–green algae are toxic, and even toxic species do not always produce toxins.
Many blue-green algal species are able to float and can sometimes be seen as green scums on water, or they just colour the water green. For more information on identifying blooms, use the Key to Blooms.
Toxic marine and estuarine algae can also affect recreational water use. Some of these algae produce toxins that can cause illness if ingested and others can cause skin irritations. These algae often cannot be seen, but some cause red coloration to water a phenomenon known as red–tides.