Algal blooms are naturally occurring phenomenon, wherein the sudden increase in the population of algae takes place. Algae bloom does not choose certain type of water; it occurs in both freshwater and marine environments. Algae on ponds and lakes are the most popular environment for these organisms.

Little is known about algae blooms because there have been no specific studies that delve on its real nature.

Scientists believed that algae have existed several billion years ago. They are one of the earliest forms of life that formed blooms along coasts and lakes. Weren’t for the algae, there would be no forms of life today. When the earth was formed, these tiny organisms were created and they produced large volume of oxygen that was taken up in the atmosphere. To make things simpler, algae were responsible for releasing sheaths of oxygen, the element essential to life.

Although algae are deemed as the origin of life on earth, these organisms are much considered as damaging threats to marine life. Algae produce soup-like blooms in freshwaters; otherwise, in marine environment, algal bloom can blanket an entire seafloor swiftly within an hour or two. Massive algal bloom has been spotted in Baltic Sea coast, turning pristine water into fetid yellow-brown sludge that locals refer to as “rhubarb soup.”

Harmful algae bloom or toxic algal bloom (HABs) arise when algal species discharge neurotoxins, poison produced from stressed and dying algae, followed by climate change. The exact number of the species of algae around the world remains undetermined; otherwise, there are around 3,000 species of algae abundant in the fresh waters of Australia, but there is roughly huge percentage of algae discovered every year.

One or few species of phytoplankton is responsible for blooms that can only be recognized through the discoloration of water. The discoloration of water can be yellow, brown, red, or green, most commonly referred to as “red tide.” Red tide is triggered by numerous accumulation of algal bloom in coastal waters. When algal bloom spread throughout the water, it depletes the oxygen contents and emits toxins that are harmful to humans and animals. Bright green blooms may also occur from the toxicity of blue-green algae. Most algal blooms are the outcome of too much concentration of phosphorous and nitrogen in the water. Dead algae can worsen the problem, because the bacteria that feed on rotten algae use the remaining dissolved oxygen needed by plants and fish to survive. When algae consume all the dissolved oxygen, many fish and other aquatic animals will die due to suffocation. High densities of algal blooms pose serious biological effects on marine wildlife.

The occurrence of algal blooms has been a major concern around the world. The bloom of toxic species can inflict diseases to humans such as gastroenteritis, lung irritation, and skin disorders. Severe intoxication may lead to death or paralysis to humans and animals.

Aside from health risks to humans and animals, harmful algal bloom can cause major economic problems to places plagued with algae. There are several states in U.S. such as New England, Texas, and Florida, including Australia, that had suffered much from economic loss when HABS dominated the coasts and commercial fisheries.