Yahoo News explains: The tiny algae causing big problems in Florida

Kate Murphy

Tiny algae are causing big problems along a 100-mile stretch of Florida’s Gulf Coast. A red tide, or harmful algal bloom, is a colony of microscopic algae growing out of control, often turning the water red.

Red tides aren’t anything new to Florida — they usually happen in the late summer and last three to five months. But this one has lasted for more than nine months.

How is the red tide wreaking havoc?

It is killing marine life: The harmful algae species, Karenia brevis, emits harmful toxins that can paralyze fish and infiltrate sea and freshwater plants eaten by marine life.
When the masses of algae die off, the process of decay can also deplete oxygen in the water so that animals either die or leave the area.

It is harmful to humans: Toxins from red tides can also be released into the air and can cause respiratory issues, eye irritation or asthma, according to the National Oceanic and Atmospheric Administration.

Shellfish are unsafe to eat: Filter-feeding animals such as mussels and oysters can accumulate the harmful toxins, making the animals toxic to humans if ingested.

What fuels the harmful algal blooms?

Sunlight, slow-moving water and nutrient pollution from inland sources, like fertilizers, can wash into the ocean. NASA says it is possible that Hurricane Irma could have something to do with it when heavy winds took nutrients and dropped them in coastal waters.