Last Updated on October 2, 2023

Sand dollars are fascinating marine animals that belong to the class Echinodermata, which also includes sea urchins, sea stars, and sea cucumbers.

They are flat, oval-shaped creatures with a five-petaled design on their backs, which helps with their identification.

Sand dollars are filter feeders, and they sustain themselves by consuming tiny plankton and other organic matter, which they filter through their tube feet.

Live Sand Dollar (Mellita sp.) trying to bury itself in beach sand
Moving sand dollar at the beach

Sand dollars are a popular beachcombing find, and their five-petaled designs make them a beautiful addition to any collection.

Sand dollar remains are often found in shallow, sandy areas, and they can be easily identified by their five-petaled designs.

They are a popular beachcombing find, and their delicate beauty makes them a welcome addition to any collection.

However, it is important to handle sand dollars carefully, as they are fragile and can easily be damaged.

If you find a sand dollar on the beach, be sure to pick it up gently and place it back in the sand where you found it.

Habitat and Distribution

Sand dollars are widely distributed marine animals found in tropical and temperate waters across the globe.

These fascinating creatures typically inhabit shallow sand or mud bottoms, making coastal areas and intertidal zones their preferred habitats.

With their unique ability to skillfully burrow into the sandy substrate, they can effectively conceal themselves from potential predators, ensuring their survival in these environments.

You can spot sand dollars in various locations throughout the United States, including states such as North Carolina, South Carolina, Florida, California, and Texas.

Additionally, they can be found in coastal areas of Mexico. These regions provide ideal conditions for sand dollars to thrive and contribute to the marine ecosystems.

Some of the most popular beachcombing locations for sand dollars include the shores of Cape Hatteras National Seashore in North Carolina, the beaches of Isle of Palms in South Carolina, and the coastal beauty of Juno Beach in Florida.

Moreover, La Jolla Shores in California, South Padre Island in Texas, and the enchanting Holbox Island in Mexico offer excellent opportunities to encounter these unique creatures in their natural habitats.

Reproduction of Sand Dollars

Sand dollars reproduce through sexual reproduction, a process that involves both male and female individuals.

The male sand dollar releases sperm into the water, where it fertilizes the eggs released by a female sand dollar. Once the eggs are fertilized, they develop into larvae.

These tiny larvae drift in the water column for a period of time before eventually settling on the ocean floor and metamorphosing into young sand dollar adults.

Types of Sand Dollars

There is a rich diversity of sand dollars, with over 200 species identified worldwide. Of these, several species are widespread in the United States.

Dendraster excentricus

Common name: Atlantic sand dollar
Range: Atlantic Ocean from North Carolina to Florida
Size: 2-3 inches in diameter
Distinctive features: Five-petaled design, eccentric shape
Habitat: Shallow, sandy areas
Diet: Filter feeder
Reproduction: Sexual reproduction

The Atlantic sand dollar is the most common sand dollar species in the United States. It is found in the Atlantic Ocean from North Carolina to Florida.

This species is easily distinguishable by its five-petaled design and its eccentric shape.

The shape of the Atlantic sand dollar is what gives it its name.

The “excentricus” part of the name refers to the fact that the center of the five-petaled design is not in the center of the sand dollar’s body.

Atlantic sand dollars are filter feeders, which means they eat tiny plankton and other organic matter by filtering it through their tube feet. They are also hermaphrodites, which means that they have both male and female reproductive organs. Atlantic sand dollars reproduce sexually by releasing sperm and eggs into the water. The fertilized eggs hatch into larvae, which drift in the water column for a period of time before settling on the bottom and becoming adults.

Mellita quinquiesperforata

Common name: Keyhole sand dollar
Range: Pacific Ocean from California to Mexico
Size: 1-2 inches in diameter
Distinctive features: Five distinct holes on the back
Habitat: Shallow, sandy areas
Diet: Filter feeder
Reproduction: Sexual reproduction

The keyhole sand dollar is a species of sand dollar that is found in the Pacific Ocean from California to Mexico.

This species is characterized by five distinct holes on its back. The holes are arranged in a star-like pattern, and they are used by the sand dollar to breathe.

Keyhole sand dollars are filter feeders, which means they eat tiny plankton and other organic matter by filtering it through their tube feet.

They are also hermaphrodites, which means that they have both male and female reproductive organs.

Keyhole sand dollars reproduce sexually by releasing sperm and eggs into the water. The fertilized eggs hatch into larvae, which drift in the water column for a period of time before settling on the bottom and becoming adults.

Clypeaster rosaceus

Common name: Pink sand dollar
Range: Caribbean Sea and Gulf of Mexico
Size: 1-2 inches in diameter
Distinctive features: Pink or orange coloration
Habitat: Shallow, sandy areas
Diet: Filter feeder
Reproduction: Sexual reproduction

The pink sand dollar is a species of sand dollar that is found in the Caribbean Sea and the Gulf of Mexico.

This species is known for its pink or orange coloration. The coloration is caused by a pigment called carotenoid, which is also found in carrots and other orange-colored foods.

Pink sand dollars are filter feeders, which means they eat tiny plankton and other organic matter by filtering it through their tube feet.

They are also hermaphrodites, which means that they have both male and female reproductive organs.

Pink sand dollars reproduce sexually by releasing sperm and eggs into the water.

The fertilized eggs hatch into larvae, which drift in the water column for a period of time before settling on the bottom and becoming adults.

Uses and Conservation

Throughout history, sand dollars have served various purposes in human societies.

Certain cultures utilized them as a form of currency or transformed them into beautiful jewelry.

Moreover, sand dollars have also been a source of food for certain coastal communities, and their durable shells were employed in crafting tools and decorative items.

Presently, sand dollars are often collected as souvenirs or for scientific research and educational purposes.

Nevertheless, it is essential to recognize the importance of their role in marine ecosystems.

Unfortunately, sand dollar populations have been declining due to overharvesting and habitat destruction, necessitating conservation efforts to protect these intriguing marine creatures.

How to Find Sand Dollars

If you want to find sand dollars, the best time to go beachcombing is during low tide.

This is when they will be exposed on the sand. You can also find them by snorkeling or diving in shallow waters near sandy areas.

When you find a sand dollar, be sure to handle it with care. Their skeletons are very delicate and can break easily.

If you want to keep a sand dollar as a souvenir, place it in a dry, cool location where it can remain intact for years to come.

Here are some tips for finding and protecting sand dollars:

  • Look for sand dollars in shallow, sandy areas during low tide.
  • Be careful not to step on or disturb live sand dollars.
  • If you find a dead sand dollar, handle it with care and place it back in the sand.
  • Do not take sand dollars from their natural habitat.
  • Educate others about the importance of protecting sand dollars.

How to Find Sand Dollars While Beachcombing: Tips and Techniques


close up photo of a sand dollar
Close up photo of a sand dollar at the beach. Photo by Brandon Imbriale on Pexels.com

10 Interesting Facts About Sand Dollars

The Name “Sand Dollar” Comes From the Appearance of Their Skeletons

The name “sand dollar” comes from the appearance of their skeletons, which are called tests.

The tests of dead sand dollars are often washed ashore and bleached white by the sun.

The tests lack the velvet-like skin of spines that live sand dollars have, which is why they appear so smooth.


Sand Dollars Are Filter Feeders

Sand dollars are filter feeders, which means they eat tiny plankton and other organic matter by filtering it through their tube feet.

The tube feet are small, flexible appendages that protrude from the sand dollar’s body. The tube feet are covered in mucus, which helps to trap food particles.

The sand dollar then moves the food particles along its body to its mouth, where they are eaten.


Sand Dollars Have Five-Petaled Designs on Their Backs

Sand dollars have five-petaled designs on their backs. These designs are actually the remains of their spines, which have been worn away over time.

The spines were used for protection and movement. The five petals are arranged in a star-like pattern, and they are often used to identify different species of sand dollars.


Sand Dollars Can Burrow into the Sand

Sand dollars can burrow into the sand to hide from predators. They can also move around by using their spines.

The spines are used to push the sand dollar through the sand. Sand dollars can bury themselves completely in the sand, leaving only their five-petaled designs visible.


Sand Dollars Reproduce Sexually

Sand dollars reproduce sexually. The male sand dollar releases sperm into the water, where it is fertilized by the eggs of a female sand dollar.

The fertilized eggs hatch into larvae, which drift in the water column for a period of time before settling on the bottom and becoming adults.


There Are Over 200 Species of Sand Dollars in the World

There are over 200 species of sand dollars in the world. Some of the most common species include Dendraster excentricus, Mellita quinquiesperforata, and Clypeaster rosaceus.

Dendraster excentricus: This species is the most common sand dollar in the United States and is found in the Atlantic Ocean from North Carolina to Florida.

Mellita quinquiesperforata: This species is found in the Pacific Ocean from California to Mexico and is characterized by its five large holes on its back.

Clypeaster rosaceus: This species is found in the Caribbean Sea and the Gulf of Mexico and is known for its pink or orange coloration.


Sand Dollars Have Been Used for a Variety of Purposes Throughout History

Sand dollars have been used for a variety of purposes throughout history.

In some cultures, they were used as money or jewelry. They were also used as a source of food, and their shells were used to make tools and ornaments.

In some Native American cultures, sand dollars were believed to bring good luck. They were often used in rituals and ceremonies, and some tribes used them as protective talismans.


Sand Dollars Are an Important Part of the Marine Ecosystem

Sand dollars are an important part of the marine ecosystem.

They help to filter the water and provide food for other marine creatures. Their populations are declining due to overharvesting and habitat destruction.

Sand dollars help to keep the water clean by filtering out algae and other small organisms. They also provide food for other marine creatures, such as fish and crabs.

Moreover, sand dollars play a vital role in the nutrient cycling of marine environments.

When they die and decompose, their remains release essential nutrients back into the water, supporting the growth of marine plants and phytoplankton.


Sand Dollars Can “Chew” Their Food

Sand dollars have a small mouth on their underside, which is surrounded by five teeth. The teeth are used to grind up food particles before they are swallowed.

This process is known as “chewing.”

Furthermore, sand dollars have a unique adaptation that allows them to “breathe” by absorbing oxygen through their body surface, a process called cutaneous respiration.


Sand Dollars Are Vulnerable to Overharvesting

Sand dollars are vulnerable to overharvesting. They are often collected for their beauty or their supposed magical properties.

However, overharvesting can have a negative impact on sand dollar populations.

As responsible beachcombers, we must ensure that we only collect sand dollars that are no longer living, leaving the live ones to contribute to the marine ecosystem.


Group of Sand dollars in Monterey Bay Aquarium
Group of live sand dollars in Monterey Bay Aquarium

Sand Dollars FAQs

Are sand dollars rare?

No, sand dollars are not rare. However, some species of sand dollars are more rare than others.

For example, the Dendraster excentricus sand dollar is the most common species of sand dollar in the United States, but it is considered a threatened species in some areas.


Do sand dollars have eyes?

No, sand dollars do not have eyes. They have a small, light-sensitive spot on their underside, but this is not an eye.

This spot is called a papilla, and it helps the sand dollar to sense light and dark.

Do sand dollars bring good luck?

In some cultures, sand dollars are believed to bring good luck.

For example, in some Native American cultures, sand dollars were believed to protect against evil spirits.

Sand dollars are often given as gifts or souvenirs, and they are sometimes used in jewelry or other decorative items.


Were sand dollars ever used as money?

Yes, sand dollars were used as a form of currency in some cultures. For example, the people of the Caribbean Sea used sand dollars as currency for centuries.

They were also used as money by the indigenous people of North America, such as the Cherokee and the Choctaw.

Sand dollars were used as money because they were durable and easy to transport. They were also relatively rare, which made them valuable.

However, the use of sand dollars as money declined in the 19th century as European coins became more common.

Today, sand dollars are no longer used as money, but they are still a popular souvenir for beachcombers.

They are also sometimes used in jewelry and other decorative items.


Are sand dollars living creatures?

Yes, sand dollars are living creatures.

They are marine animals that belong to the class Echinodermata, which also includes sea urchins, sea stars, and sea cucumbers.

Most of the sand dollars you find at the beach are already dead, as these creature cannot survive long outside of water.

Live sand dollars are covered in a soft, velvet-like layer and able to move, which makes them easily distinguishable from the shells you find while beachcombing.


Are sand dollars dangerous?

No, sand dollars are not dangerous. They are filter feeders, and they do not have any teeth or other sharp spines.

However, they can be fragile, so it is important to handle them carefully.

If you find a sand dollar on the beach, be sure to handle it with your hands and avoid stepping on it.


Are sand dollars endangered?

Some species of sand dollars are endangered.

This is due to a number of factors, including overharvesting, habitat destruction, and climate change. Overharvesting is the biggest threat to sand dollar populations.

Sand dollars are often collected for their beauty or their supposed magical properties.

However, overharvesting can have a negative impact on sand dollar populations.


Do sand dollars move?

Yes, sand dollars can move.

They use their spines to push themselves through the sand.

They can also burrow into the sand to hide from predators. Sand dollars can move about 10 feet per hour.


Do sand dollars bite?

No, sand dollars do not bite.

They do not have any teeth or other sharp spines, so you don’t have to worry about approaching a live sand dollar as it cannot hurt you.

However, their spines can be sharp, so it is important to handle them carefully.


Can you eat sand dollars?

Yes, you can eat sand dollars.

Despite being edible, they are not a popular food. They have a bland taste, and they can be difficult to digest.

Sand dollars are also high in sodium and cholesterol, so they should not be eaten in large quantities.


How long can a sand dollar live out of water?

A sand dollar can only live out of water for a short period of time.

They will dry out and die if they are not returned to the water within a few hours.

If you find a sand dollar on the beach, be sure to return it to the water as soon as possible.


Can you keep a sand dollar as a pet?

No, you should not keep a sand dollar as a pet.

They are not a good fit for captivity. They need to be in the ocean to survive, and they are delicate creatures that can easily be injured.

If you want to enjoy sand dollars, it is best to observe them in their natural habitat or collect them as souvenirs from the beach, making sure they are no longer living.


Read also: Best Beaches for Beachcombing in the USA

Leave a Reply