The Dangers of Red Tide

A cartoon depiction of red tide.

A cartoon depiction of red tide.

If you live in Florida, there is a good chance you are familiar with red tide – especially if you have been in Florida in the last decade or so, as three major red tides have occurred in recent years along the Gulf of Mexico coastline. This colorful phenomenon is not only highly noticeable when it occurs in local waters, but it also has a large affect on the local ecology and economy as well.

Despite its somewhat morbid appearance, giving seawater the distinct tinge of a deep blood-red, red tide is actually the result of something somewhat unexpected. When certain types of algae, called dinoflagellates, are present in high amounts, it causes what is known as an algal bloom. It’s important to note, however, that not all algal blooms will result in a red tide, as not all types of algae are red or brown in color, and oftentimes their concentration is not actually high enough to cause a change in the water’s appearance.

It also important to note that the title of “red tide” is not entirely accurate, especially as the phenomenon has nothing to do with the tides at all. Furthermore, harmful algal blooms can occur just as easily with dinoflagellates that are not red in color, and which in fact blend in so well with the natural coloring of the water that they are almost entirely undetectable. It is these algal blooms that are perhaps the most dangerous, because their presence is much less obvious while their affects can be just as disastrous.

But what makes algal blooms so dangerous? In terms of direct causes to the local wildlife, the affects can be quite deadly. Karenia brevis, the microorganism which is present in most Florida cases of red tide, produces brevotoxins that are highly poisonous to marine life. These toxins build up in seagrass and sediment, which is then fed on by primary consumers and eventually eaten by predators, negatively affecting and killing wildlife at all stages of the food chain.

While it’s not uncommon for red tide and other algal blooms to kill off large populations of fish and manatees, these harmful affects reach human beings in the area as well. Economically, the affects on marine life cause disruptions to fisheries and local restaurants, as animals containing brevotoxins are unsafe for human consumption. Furthermore, fishermen, beachgoers, and boaters can be affected simply through air exposure, as certain algal blooms can cause eye irritation and respiratory problems, especially in those with respiratory conditions already present.

Fortunately, no major red tides have occurred in South Florida during the 2015 season, and the coastlines and estuaries of the Everglades can easily be enjoyed on an exciting airboat tour. To view the Everglades ecosystem at its best, schedule a Florida swampland tour that the whole family can enjoy today.