Toxic algae bloom covers South Australian beaches

Photo:Depositphotos

The presence of foam on some South Australian beaches has sparked international interest with reports of the adverse effects of the foam on the marine ecosystem and human health. More than a hundred swimmers and surfers have developed flu-like symptoms after simply inhaling the sea mist. The foam is also certainly harmful to marine life including sea dragons, octopus and fish, many of which have been found dead on the beaches.

The foam is caused by a tiny species of planktonic algae called Karenia mikimotoi. The foam samples were collected from Waitpinga Beach, Petrel Cove, and the Encounter Bay and Parsons Headland boat ramps. The single-celled microbial algae are naturally found in seawater around the world and are called phytoplankton. Their main role is to capture sunlight and produce up to half of the oxygen in our atmosphere. There are more than 100,000 known species of microalgae, which can be found in every liter of seawater.

Under certain conditions only one type of microalgae can accumulate in an area and dominate the others. Currently, the dominant species is a toxic type of algae that has infested Australian beaches. In addition to fish, harmful algae blooms threaten invertebrates and marine mammals, including seals and whales. Each of the hundreds of species of toxic algae produces a specific type of toxin.

Toxic algae blooms occurred on Australian beaches in 2012, affecting over 300 square kilometers of abalone farms, causing a loss of production of A$525 million. Fortunately, once the algal blooms have passed, the marine environment recovers quickly.

Source:Guardian