Have You Seen Red Tide on the Beach?

Flow map of red tide in Florida (credit to Start1)

Term of “red tide” refers to blooming of algae in the oceans. It is due to nutrients from ocean floor rising to the surface.

Nutrients are excellent source of foods for different kinds of algae. Some algae are harmful, others are not.

It is natural phenomena, and could be happen any where in the world. The time length of red tide is about two weeks.

Harmful algae called Karenia brevis, could color ocean surface to be red if they are in great number or dense enough in the water.

In the coast of Florida, this algae is appearing from Spring to Summer, and blooming in the November every year.

The longest red tide in Florida in recent years was about 16 months, from around late 2017 persist to early 2019. 

Dead of marine animal due to Florida red tide

(credit to Ivy Yin)

The Karenia brevis released neurotoxin, the effects of this toxic on environments are following:

- killing and contaminating wildlife such as fish, shellfish, birds, dolphin and sea turtles.

- breathing problems to human

Fishes are sensitive to neurotoxin. Commercial fishes which are salmon, cod, flounder, American pollock and Atlantic herring could die in an hour after exposure to neurotoxin.

This 16 months red tide caused lost million of dollars to Florida state economic, especially to business relate to tourism industries.

Have you seen red colors of sea in front of any beaches?