It is not clear where sand fleas got their name from given that they are far from being actual fleas. The prevailing wisdom is that sand fleas may have gotten their name from the distinct flea-like bite marks that these critters leave behind when they bite humans.
The name sand flea is used as a general term to describe an entire genus of Emerita that includes up to 11 different species of sand fleas. Sand fleas are under the order Decapod and are the favorite bait for surf fishermen in many parts of North America and around the world.
Sand fleas are also a delicious snack in some countries, most notably in parts of India and Thailand.
There is a lot of confusion about what sand fleas are, given the general use of the term. We hope to clear everything up in this article.
What are Sand Fleas?
Despite what the name suggests, sand fleas aren’t actual fleas. In fact, they are not insects at all, but rather crustaceans. Sand fleas are more closely related to lobsters, crabs, and crayfish than actual fleas or ticks.
Other names for sand flea include sand crab, sand bug, beach flea, sand hopper, and sand fiddler.
Sand Flea Appearance – Sand fleas have a barrel-shaped body and are sometimes barely visible to the naked eye, measuring between ½ inch and 1 inch long. Female sand fleas are larger than their male counterparts, growing up to 2 inches long. Male sand fleas measure about ¾ inches long.
Juvenile or young sand fleas are dark-brown to black, although some appear to have a slightly tan color. Adult sand fleas are lighter in color and look almost beige, white, and in some cases, translucent. It is widely thought that these critters can alter their color slightly to match the sand on the beach where they reside.
The crustaceans have 5 sets of tiny legs which they use to dig into the sand and/or paddle through the water.
Sand Flea Anatomy – Sand fleas have gills which they use to breathe and need oxygenated water to survive. These crustaceans have a telson located at the rear of their underbelly where you might find bright-orange eggs on a female sand flea. This telson also protects the soft underbelly of the crab. As is common with crusteceans, sand feas have a hard exoskeleton.
Sand Flea Habitat – Sand fleas typically live in coastal areas and sandy beaches but they also live in desert areas and marshes. These crustaceans are found along the coasts of the United States, including along the Atlantic coast of Africa.
They primarily live on beaches and burrow beneath the sand, tail-end first, and create small colonies at the swash-zone. The two species of sand flea found along the coasts of North America are Emerita analonga and Emerita talpoida.
Sand Flea Feeding Habits – Sand fleas primarily feed on organic debris including seaweed. The little critters lift their antennae-like feeders to catch the organic debris as the waves recede.
Sand fleas also have a taste for blood and will bite humans given the opportunity. These critters are most active at dawn and dusk.
Sand Flea Bites on Humans
Although sand fleas primarily feed on organic debris such as seaweed and plankton, these critters will occasionally bite humans given the chance. Female sand fleas are more susceptible to biting humans, and use the protein from the blood as nutrition for laying eggs.
Sea flea bites typically occur around the legs and ankles, although the bites may occur anywhere on the body if you are lying down. The critters can’t jump very high, usually 20 cm, which explains why most bites occur on the lower body.
Sand flea bites look a lot like your regular flea bites; 2-3 bites in clusters with small, red bumps. The red bumps typically have red hallow or ring surrounding the bite. Sand fleas inject an anticoagulant to ensure that blood continues to flow while they feed. A reaction from the crustacean’s saliva causes symptoms including redness, itchiness, and pain on the victim.
Are Sand Fleas Dangerous?
You may have heard horror stories about female sand fleas burrowing into your skin to lay eggs. While this is true, a different kind of sand flea, the Tunga penetrans or chigoe flea, is responsible for this nightmarish scenario.
The chigoe flea is an insect, unlike the crustacean sand flea described so far in this article. Chigoe fleas are native to Central and South America but have been inadvertently introduced to India and sub-Saharan Africa.
Cases of Tungiasis, which is what happens when the chigoe flea burrows into the skin, are extremely rare in North America. The chigoe flea is also rare in North America.
Although commonly referred to as a sand flea, the chigoe flea is more of a sand fly than a flea.
How to Treat Sand Flea Bites
Other than the small risk of sand fleas laying eggs in your skin in the unlikely event you encounter a chigoe flea, most people do not experience adverse reactions to common sand flea bites save for the itching, scratching, and painful sensation. The discomfort should go away on its own in a few hours but meanwhile:
- Avoid scratching the bite. Aside from making the itch worse, breaking the skin will leave you open to all kinds of infections. The beach is filled with sand, debris, and tiny pests that put you at high risk of infection.
- Most over-the-counter anti-itch creams are great for soothing sand flea bites. It is a good idea to bring topical creams with you to the beach, preferably hydrocortisone creams. Aloe-Vera and oatmeal are also great home remedies for sand flea bites.
- In case of severe itching or discomfort, consider taking antihistamines or ibuprofen to help with the discomfort. Over-the-counter antihistamines are great for alleviating the itching while ibuprofen should take care of the pain.
- Seek medical attention immediately you notice an adverse reaction to the bite. Symptoms of a severe allergic reaction to sand flea bites include nausea, fever, headache, dizziness, and swelling of the lymph nodes.
Tips for Avoiding Sand Fleas and Preventing Bites
Sand fleas can be a nuisance but that doesn’t mean that you have to swear off going to the beach. There are a few precautions that you can take to keep yourself safe from sand flea bites.
- Avoid the beach at dawn or dusk if possible. Sand fleas are most active during these times and spend the rest of their day buried in the sand. Avoiding the beach during peak times may be all you need to keep the pests at bay.
- Do not lie directly on the sand. Use a towel as a barrier between your body and the sand. Better yet, take a beach chair with you to create as much distance between your body and the sand. Bonus points if you can get a lounge chair to put your feet up!
- Wear shoes on the beach. While it may not be possible to stay off the sand altogether, wearing shoes on the beach should reduce your attractiveness to breeding female sand fleas with a taste for blood.
- Avoid the beach shortly after rain. Sand fleas tend to become more active and exposed immediately after rain regardless of the time of day.
- Use a DEET repellent before going to the beach. DEET is a very effective repellent for sand fleas among other parasites.
Beach enthusiasts may be relieved to know that sand fleas in North America rarely transmit diseases. Aside from the small risk of a chigoe flea burrow through your skin to lay eggs, most sand flea bites are virtually harmless except for the pain and itchiness.
Most people also don’t experience severe or adverse reactions to sand flea bites. Still, it is important to take precautionary measures including carrying topical ointments, applying DEET-based repellents, and taking the aforementioned precautions before visiting the beach.
Sand flea bites can take the fun out of a perfectly beautiful day at the beach, but all this is largely avoidable and even treatable in a worst-case scenario.