Marine Mammal Bone Fragment
Cetacea and Sirenia
Markings and exact colorations may vary.
A dense, water-worn chunk of fossil bone with a spongy interior, from a whale, dolphin or sea cow.
- Typical size
- 1–8 in
- How often it turns up
- Common
- Collecting
- Archaeological, leave in place
- Handling
- Safe to handle
Vertebrate fossils collected from state-owned land or submerged bottoms in Florida require a fossil permit from the Florida Museum of Natural History. Beach-washed finds above the waterline are generally fine, but know your site. Fresh marine mammal bone is federally protected — leave it and report it.
How to tell it apart
- Spongy honeycomb interior visible at breaks
- Dense, dark, water-rounded
- No shell layers or growth rings
Where to find these in Florida
Beaches rated very good or excellent for fossils. Each page shows today’s score, the best window and access details.
- Caspersen Beach · Venice
- Englewood Beach (Chadwick Park) · Englewood
- Stump Pass Beach State Park · Englewood
- Turner Beach · Captiva
- Turtle Beach · Siesta Key
Found one?
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More fossils in the field guide
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