Sargassum
Sargassum species
Markings and exact colorations may vary.
Golden-brown floating seaweed with small berry-like air bladders, washing up in mats.
- Typical size
- Clumps a few inches to huge mats
- How often it turns up
- Seasonal, sometimes abundant
- Collecting
- Check local rules
- Handling
- May irritate skin
Leave it on the beach — it feeds dunes and wildlife.
Rotting mats release hydrogen sulfide gas; tiny animals in it can sting. Rinse hands after handling.
How to tell it apart
- Golden-brown branching seaweed
- Small round air bladders like berries
- Narrow, toothed leaf-like blades
Where to find these in Florida
Beaches rated very good or excellent for tidepool life. Each page shows today’s score, the best window and access details.
- Bathtub Reef Beach · Stuart
- Anne's Beach · Islamorada
- Bahia Honda State Park · Big Pine Key
- Bathtub Beach · Stuart
- Caspersen Beach · Venice
- Curry Hammock State Park · Marathon
- Fort Zachary Taylor Historic State Park · Key West
- Harry Harris Park · Tavernier
- Higgs Beach · Key West
- John Pennekamp Coral Reef State Park · Key Largo
- Long Key State Park · Long Key
- Marineland Beach · Marineland
Found one?
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More tidepool life in the field guide
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