Ephemeral is a fun word. It sounds gauzy and insubstantial; there’s something romantic, too. It’s not something we really associate with nature, but we should. Nature loves an ephemeral.
There’s nothing more ephemeral than clouds, for example. They rise up out of nothing, yet tower over us, dump rain, snow, hail and whatever else they come up with, and then disappear. The Northern Lights are endlessly fascinating simply because they are so ephemeral, now you see them, now you don’t.
Ephemeral plants pop up in the spring, bloom, then fade away so that by summer you’ve entirely forgotten they were there. Incredibly, there are even animals that live out their entire out-of-the-egg lifespan in just a few weeks in the spring.
Just because it is ephemeral doesn’t mean it isn’t vitally necessary. Without those “ephemeral” clouds we wouldn’t have rain – we’d live in a desert. Ephemeral plants provide nectar sources to pollinators at a time when most plants are just barely out of winter dormancy, and ephemeral animals provide food for early emerging larger animals and hungry birds.
Spring is a great time to see many ephemeral plants. Take a woodland walk and you may see Mayapples this time of year. Like Skunk Cabbage which blooms in winter, you see it, you get used to it, and all of a sudden, it’s not there. It’s part of the fun of a woodland walk.
Vernal pools, which are sometimes called seasonal or ephemeral pools, are another temporary treat for the eyes in the spring. Many creatures love these pools – you may even see ephemeral shrimp, called Fairy Shrimp, in them. Fairy Shrimp live most of their lives as eggs encased in a tough-as-nails shell, breaking out only when sufficient water allows it. For a few weeks only, you might see them swimming madly about, finding food and mates. Eventually, they’ll lay more eggs and the process with start all over again the next time there’s standing water for a sufficient time. Ephemeral, but so cool.
We don’t usually consider this, but vernal pools are another form of a wetland. We all know how vital wetlands are to life on this planet. In natural areas, vernal pools will occur in the spring when most of the plant life – trees, shrubs, grasses, etc. – are still in winter dormancy, so they don’t absorb water the way they do at other times of the year. The water from snow and rain collects in low lying areas which will dry out when the weather warms, plants come out of dormancy and, usually, there’s less rain.
Vernal means spring, so the name makes sense as does ephemeral pool, another name for these marvelous entities. You might also call one a “drainage ditch.”
Many drainage ditches, particularly the ones that don’t drain the water away as efficiently as some might like, are nature’s best hope not only for Fairy Shrimp but for many amphibians and the food webs they support (amphibians are animals that start their lives in water but live on land as adults).
Vernal pools tend to occur on nice, basically flat, “perfect for development” land. Unsurprisingly, most of them have disappeared. Fortunately, developed land and the roads they need force developers to dig ditches to handle water.
Those little pools or ditches are a bonanza for many forms of life, most of which spend their adult life elsewhere. Frogs, toads, salamanders, newts – any and all of these appreciate these ephemeral pools. They lay eggs in them, hoping the next generation will get a good start.
They could use ponds, too, but ponds tend to have fish in them, and fish will eat the eggs and small fry. Often, they eat them all, and the entire next generation is lost. In a vernal pool, however, the eggs, tadpoles, etc., are safe from fish predation because fish need water year-round. Usually by the time the pool dries up, the amphibians move into their adulthood, where they live in air, not water. Many times, the only time you’ll get a good glimpse of these creatures is when they’re young, living in the pool; when they emerge, they hide in trees, grasses, under logs – they hide.
If you are lucky enough to have a vernal pool, you might be able to see some Fairy Shrimp, eggs, tadpoles, etc. That’s fun! Children will love seeing them, too.
Having said that, I’ll make a plea for superb sanitation around the pool. That’s right – you must keep the vernal pool clean. Don’t use it to wash off your boots. In fact, wash your boots very thoroughly before you go near the pool (This applies to ponds, too). Then wash your boots thoroughly when leaving the pool. Many people keep disinfectant and rags in their cars for this very purpose and wash their shoes/boots before they travel anywhere else. Train your children to do the same. They’ll be happy to think they’re making life better for the fascinating little creatures.
This keeps disease from spreading. There are several very nasty diseases which can wipe out these fragile creatures, many of which already are endangered. It’s a terrible thing; we are part of the vectors which spread disease around. Birds undoubtedly do the most to spread them, but we must do our part to help the animals and the food webs they support.
Now that you know, doesn’t that drainage ditch look so very inviting? Especially if it’s all full of water?
For more information, visit Wild Maryland 101 – A Marylander’s Backyard Guide at wildmaryland101.blogspot.com.
Maureen Rice is a Master Naturalist living and writing in Talbot County.