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Hike across Great Lakes dunes from the water, and you'll encounter four distinct changes in landscape and microclimate, and different plant and animal species associated with each of the four zones:
The level shore where water meets the sand is the happenin' place for humans when the weather's right. But seasonal extremes, waves, wind and rapid evaporation hit hard here, so only the hardiest (or, at least, persistent) plants and animals—gulls, flesh flies, sea rocket and digger wasps among them—can hang here long.
Here's where the grasses grow—a good thing because they stabilize the dunes. The eastern hognose snake and wolf spiders live here too, but chances are good you'll see only their respective tiptoe and swishy tracks on a summer visit; they abhor the heat and typically burrow underground until the evening's cool temps beckon.
Interdunal ponds are the hallmark of these low-lying landscapes, and though the standing shallows may appear stagnant, they teem with life—cattails, dragonflies, spring peepers, Fowler's toads and garter snakes. When the ponds dry out, stands of jack pine take over.
Farthest from the waterline, the backdunes provide an important shelter for birds migrating along the shore; they're vibrant with hemlocks, oak, maple and beech trees, as well as mosses, ferns and wildflowers. Thanks to the decay of leaves, plants and animal matter, the top layer of soil here is fertile, but just beneath lies dune sand, so erosion occurs easily, and backdunes are considered extremely sensitive habitat.