It looks like a good day for shorebirds. The winds has been blowing onshore for two whole days, but now is starting to die down. The sun is out and it’s a good time to head down to the beach and see if any wandering seabirds or shorebirds come in with the gale.
You see at once that the beach has changed; a wide swath of seaweed now covers about a third of the beach, from one end to the other. The fierce winds and ocean turbulence have dredged up the seaweed. Scanning the seaweed, you see scores of shorebirds, busy running and poking around the seaweed. What are they doing? They seem to be looking for something.
There are Plovers—these are short-billed hunters who rely on vision to find food, as their relatively large eyes indicate. They tend to run and pause, examining the area and spying out insects and tiny sea creatures. You also notice many shorebirds with long bills, and these are probing into the seaweed, and finding things to their liking.
Moving closer to inspect, you see the seaweed rolls are a tangled mess of several kinds of kelp, long strands or ribbon-like eelgrass, long tubular seaplants with a long, flat tail, and small clumps of shrubby pink carageenan. Using a stick to lift some of it, you realize it’s quite heavy, and let it drop. At once, clouds of tiny hopping insects rise up out of the seaweed!
Ugh! They look just like the fleas that infested your dog for several months last autumn—the ones it took months to get rid of. You hurry away from the seaweed, and already you feel an itch…
Wait! Before you reach for the DEET, let’s try and figure out what you are seeing.
Beach Hopper Or Sand Flea?
There are many tiny, hopping things around sandy beaches, or even in desert sands, which are known as “sand fleas” to the local residents. This is where it can get confusing.
What you’ve seen at the beach might not be a flea. It might not even be an insect. It could in fact be a “beach hopper”, which is like a tiny shrimp, and not a flea at all. So, when you read an article online that starts scaring readers about going to the beach and being attacked by “sand fleas”, first of all look and see who is sponsoring the article. It just might be a pest control company.
That said, there might be cause for alarm, especially if you’re in a tropical or sub-tropical area, where you may be really seeing a type of flea, such as the Chigoe flea—Tunga penetrans (so named because they can penetrate your skin, and the female may lay eggs in your flesh, ewww!).
Ok, prepare to be completely grossed out!
As you can see from the above video, they are quite a nuisance, and probably call for some kind of protection—the same kind you’d normally use for mosquitoes. There are also preventative measures, such as the time of day you go to the beach—please consult someone local if you are visiting a southern resort, for the best advice on avoiding these pests.
But if you are beach birding in a more northerly clime, what you are seeing is probably a tiny crustacean, a landlubbing one, mind you, which looks a bit like a shrimp (but you’d have to use a magnifying glass to tell). People call them fleas for the very same reason you thought of Snoop’s pesky infestation—they do very much look like fleas. At least to the naked eye.
And they behave the same, with an ability to flip into the air that would’ve put Louis Bertolotto’s circus fleas to shame. Their “real name” is Platorchestia platensis, formerly Orchestia agillis (as in “agile”) and it’s a sad thing that they should be confused with any kind of flea. They eat things like seaweed and tiny bits of organic debris. Plus, the really good news about them is that birds love them!
Yes, all those shorebirds messing around on the slimy masses of fresh seaweed—or the slimy masses of half-rotten seaweed—are dining on these tiny arthropods.
Many the wayward migrant songbird, blown off-course by a hurricane, lost and confused, starving, and staring down four months of winter far from the southern lands where their kin are living it up—have found their way to the beach—and survived. Despite terrible cold, if they can eat, they can stay warm enough to make it through. What they live on is the tiny misnamed “sand flea” which is active all year long. Another colloquial name for this misunderstood and maligned creature is “beach hopper.” Certainly it is descriptive, and also a more benign moniker. Now you can put away the DEET!