Toxic Algae Blooms in Australia Pose Global Threat to Marine Life

Researchers have identified a toxic algal bloom in South Australia caused by a species named Karenia cristata, which has devastated marine life over 20,000 square kilometers, killing around one million animals from over 550 species.

The bloom has been linked to a new toxin classified as brevetoxins, which can cause nerve damage in marine life and is harmful to humans when inhaled or ingested. Shauna Murray from the University of Technology Sydney highlighted the international concern regarding this emerging threat, stating that the presence of K. cristata could lead to similar outbreaks globally.

The bloom coincided with a severe marine heatwave, raising sea temperatures by up to three degrees Celsius. However, the unexpected expansion of the bloom after the waters began to cool raises questions about the specific triggers for such events.

Christopher Keneally from the University of Adelaide mentioned that the dominant species was previously thought to be Karenia mikimotoi, which does not produce brevetoxins, suggesting a significant shift in understanding these harmful algal blooms.

As the global climate continues to change, the conditions that favor algal blooms, such as rising sea temperatures and nutrient loads from urban areas, are likely to increase. This could mean that K. cristata and other bloom-forming organisms may appear in different coastal regions, posing risks to marine biodiversity and human health.

The current event in South Australia is among the most destructive and widespread algal blooms ever documented, indicating an urgent need for research into the ecological impacts and potential management of these harmful algal species.

Understanding the behavior and distribution of K. cristata is crucial as we prepare for the possibility of similar events elsewhere in the world.