Shells

Shells of various shapes, sizes, and colors can be found covering the beaches of Fort Matanzas

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Shells

As you are walking along the beach at Fort Matanzas National Monument, you may be captivated by the vibrant shells beneath your feet. Our unique location where the Matanzas Inlet opens to the Atlantic Ocean, is a zone for high wave action. As a result, creatures under the Phylum Mollusca are found here. These organisms have a hard shell to protect their soft bodies. Unfortunately, when they are found on the beach, they have typically passed, either due to predation or other impacts. Beach goers may be collectors of the beautiful and diverse shells found here. Some may be intact while others are broken apart due to intense wave action or predators.

 

Small Group of Coquina Clams on the sand

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Coquina Clam

Here at Fort Matanzas, we have the legendary coquina clam that was utilized to build the fort and many historic buildings of Saint Augustine. These beautiful clams have a variety of colors that include orange, white, pink, and purple. They are responsible for our vibrant colorful sands on the beach and intracoastal waterway. The coquina clam is a bivalve, which is characterized as an organism that has a hinge between two shells. These clams have a muscular foot that allow them to burrow into the sand in the ocean. They do this to hide from predators, and during this time they spend the day filter feeding. As omnivores, they eat suspended plant material and other detritus.

Click the image to learn more about building with the Coquina Stone.

 

Lightning Whelk on the beach with the ocean and sky in the background.

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Welks

In the sandy shallows, whelks reside, displaying different colors including white and orange to light gray and black. Whelks have a thick shell that can reach up to 9 inches in length. When viewing these shells, you may notice whirls that typically start on the right side. The lightning whelk is the exception to this, with the whirls spiraling towards the left side. Whelks are ferocious predators that use a muscular organ with hundreds of tiny teeth, known as the radula. When it is time to eat, the whelk will use the radula to scrape the hard-shell of a clam to get to the small animal living within.

 

In addition to finding these beautiful whelks on the beach, you may encounter their egg casings, which can house about 200 eggs!

 

Shark’s-eye snail on the sand with the ocean in the background.

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Snails

Snails are not only found in freshwater, but they inhabit salt water as well. Visitors are intrigued to learn about the resident shark’s-eye snail. With a globular shell, they can be easily distinguished by a whirl of blue-grey and grey-brown, resembling a shark’s eye. Similar to whelks, they are predators, using their radula to consume their prey. Interestingly, they propel themselves using millions of cilia, gliding on a cushion of their own mucus.

 

This page captures only a few of the shells that you can find at Fort Matanzas National Monument. While they may catch the eye of many visitors, it is important to remember that if we take too many of something, then others may not be able to enjoy them as well. Finally, other animals may utilize the shells as a home. Before taking a shell, always make sure to check that no resident lives in that shell. Join us in conservation efforts to keep Fort Matanzas and its residents thriving.