While the woods around metro Grand Rapids may seem somewhat lifeless and dull brown now as they shake off the long winter slumber, marshes and ponds are teeming with life.
All you need to get a front row seat to the show is a common glass jar and the initiative to get outside.
For example, stroll around the large marsh on the southeast edge of the Blandford Nature Center in Grand Rapids near its entrance gate, and you’ll find the “A Wetland Walk” wooden dock that leads out into the pond. If you lay down on your stomach on the dock and peer into the water, you will be rewarded with an closeup view of hundreds of water fleas, scuds and fairy shrimp dancing in the water. These same creatures can be found in just about any marsh and pond in a wooded area.
Scoop up some of the water in a glass jar, and you will be amazed at the energetic or graceful motions of their delicate bodies.
Easily visible to the naked eye, these three families of tiny crustaceans form an important part of the food chain for insect larvae, tadpoles and other animals that spend aspect of their lives in the pond, says Wildlife Education Specialist Sarah Chertos.
“The marsh turns out to be the home for a lot of animal babies – we like to call it our nursery when we talk about it to school groups,” she says. “Insect larva for dragonflies and damsel flies, frogs, turtles, baby ducks and goslings all spend some time at the marsh as they grow into adults.”
Chertos says this is a perfect time to view the activity of daphnia, also called water fleas, and scuds before insects start laying their eggs in the water and pollywogs emerge. You can tell the difference between among these tiny crusteceans by the way they swim. Water fleas get around in a jerky and darting motion, while the scuds appear to swim on their sides with a more constant motion. Fairy shrimp are by far the most graceful, swimming on their backs with undulating leaflike appentages.
Water fleas feed on decaying plants, algae and microorganisms that they filter from the water as they move, while the larger scuds eat just about any organic debris usually found at the bottom of the pond. In turn, the daphnia, and scuds become food for insect larvae and the tailed aquatic larva of amphibians such as frogs, toads, newts, and salamanders.
“The kids from one of our school groups still talk about the time we put a sample of the marsh water under a microscope in our wet lab to view a dragonfly larva,” Chertos says. “A scud happened to be in the same sample, and the larva captured it and ate it while we were watching. It was awesome!”