Algae causes the water at Bondi Beach, Australia to turn bright red. But red tides don’t have to be red at all
A red tide is when a large concentration of certain species’ of algae gather to give the water a different color. This is often red, but can also be brown or green, and more rarely, purple or pink. It’s not actually the water that changes color, though. The organisms themselves are just colored, and when they are in such a high concentration it appears as though the water has changed color.
If you ever come across a red tide, be sure to do some research before spending too much time near it. Some red tides give off toxic gases which can cause sickness in those near the water. Death isn’t likely for those who swim in the red tide, but it can cause skin irritation and burning depending on the type.
The organisms that cause the red tide are not overly dangerous to humans directly, but they can have a pretty big effect on us. When certain types of algae gather, it makes the fish in those waters toxic. This causes a disruption in the fishing industry and sometimes causes sickness, and even death, in those who eat the fish. The last reported fatalities were two people in January of 2013 in Malaysia.
Researchers are trying to phase out the use of “red tide” to describe the phenomenon in favor of calling them “algae blooms.” There are a few reasons for this. First, and most obviously, the blooms are not always red. Secondly, they aren’t caused by the tides, but rather other factors which attract the algae. Lastly, the term “red tide” is often used imprecisely to refer to a wide variety of algae species.
Toxic or not, these algae blooms sure are beautiful.