Sargazo
A brown seaweed that arrives in floating mats from the Atlantic and piles up on the shore, mostly between spring and autumn. As it rots it smells of sulfur and clouds the water, though it is not toxic to touch. The east and south coasts usually get more than the north, and the amount shifts week to week.
Example
In sargassum season, check recent photos rather than brochure shots before choosing a beach, because the same beach changes within days.
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Frequently asked questions
Is it dangerous to swim in?
The seaweed itself is not toxic, but the gas it releases while rotting irritates airways and some people's skin.
Which beaches escape it?
It changes each season. As a rule the north and west coasts get less than the east and southeast.
