Blue-green Algae

Blue-green algae are naturally occurring microscopic organisms whose scientific name is cyanobacteria. They are similar to bacteria, but also share some of the features of algae. Where conditions are favourable, they are able to multiply rapidly and form blooms. These blooms are not flowers as such; they look more like cream of broccoli soup that has been poured into the water. Although most blue-green algae blooms are harmless, a small percentage can produce toxins that can be harmful to human and animal health.

What causes blue-green algae blooms?
Blue-green algae blooms can be triggered by a variety of factors including elevated water temperature, weak current and water stagnation. Inceased levels of phosphorus also play a part in making the aquatic environment more amenable to blue-green algae blooms.

Phosphorus is a naturally occurring component of our lakes and waterways. However, many human activities can lead to higher phosphorus levels in aquatic environments. Excess phosphorus is found in wastewater from septic systems, and drainage and runoff from deforested land, farmland or shorelines that have been enriched with fertilizers, compost and solid or liquid manure. Eventually, and especially after hard rain, the phosphorus finds its way into our rivers and lakes. When present in excessive amounts, phosphorus can stimulate the overgrowth of certain organisms that are native to these bodies of water.

Recognize it, report it, prevent it

Report it to: alspavdm@gmail.com

Learn to Recognize It
Blue-green algae blooms may be difficult to distinguish from other aquatic phenomena. This is why the Ministère du Développement durable, de l’Environnement et des Parcs (MDDEP) has produced a helpful guide to identifying them. The guide is available from your regional MDDEP office and online HERE

Report It!
Do you believe you have witnessed a blue-green algae bloom? Report it! Please take a photo and send it to us at alspavdm@gmail.com.

Has the bloom you noticed this morning already disappeared? Report it anyway, since blooms move around beneath the surface of the water and can reappear at a different location later on.

Prevention is the Best Remedy
It is not easy to prevent the overproliferation of blue-green algae, but the best way is to attack the source of the problem. Above all, we need to avoid the release of excess phosphorus into our lakes and rivers and here are some simple ways we can help:

  • Restore shoreline vegetation, because the roots of shoreline vegetation retain the phosphorus instead of it flowing into the water system. PLANT MORE, MOW LESS!!!

  • Limit the use of chemical fertilisers, compost and manure on lawns.

  • Use phosphate-free soaps and cleaning products

  • Ensure proper functioning and regulatory compliance of septic tanks.

Preventing phosphorus overload in surface water and upstream watersheds remains the best way of countering blue-green algae proliferation. This preventive action requires collective efforts on the part of citizens, enterpises and municipal and provincial government authorities.