Red tide causes huge fish kill in Gulf of Mexico

Thousands of fish, crabs and sea turtles were reported dead or dying off the Gulf of Mexico along the stretch of Pasco to Dixie counties according to the Florida Fish and Wildlife Conservation Commission. The agency collected water… and fish samples from six spots off the Hernando County coast and have confirmed red tide is indeed present in the area. Karenia brevis, a Florida red tide organism, in particular is in bloom, but the agency says this particular organism naturally occurs in the gulf and has been around since the 1700s.

Taking satellite images with the help of University of South Florida’s Optical Oceanography Lab, agency personnel were able to confirm that the bloom has spread to an area about 50 miles wide and 80 miles long located between 40 and 90 miles from the shore. The bloom, however, is not expected to grow or move in the coming days.

Red tide, or algal bloom, happens when algae accumulates and grows in the water too quickly. Overrunning the affected area, it results in a reddish-brown color on the water’s surface where it got its name from. Red tide can be lethal to marine life because an overgrowth of algae competes with other creatures for oxygen in the water, depleting oxygen levels to a point that supply becomes insufficient for survival. Other times, red tide is a threat because the bloom can release natural toxins that other marine life cannot combat. These natural toxins are also absorbed by shellfish, making oysters, shrimps, clams and others dangerous for people to consume.

The onset of red tide usually signifies alarm but it is actually a natural occurrence that usually happens during summer. Also, just a small portion of the bloom can produce toxins that kill marine life so fatalities associated with red tide are typically due to the lack of oxygen in the water. Creatures that do encounter red tide though don’t always die. Some may choose to leave the area because resources are no longer enough to sustain life.

But just because an algal bloom can be problematic does not mean that it is completely bad. Algal bloom is actually necessary for ocean life because the tiny plants are eaten as food by many animals in the water. In fact, algae is a primary source of energy for the ocean food web. Only when algae reaches uncontrollable levels does it become a reason for concern.

 

Photo caption: Red tide happens all over the world and can be caused by around 200 known organisms. Warm waters promote algal growth that’s why red tide usually happens during the summer.
(Photo : Alejandro Diaz)

View original article at: Red tide causes huge fish kill in Gulf of Mexico

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