Lake Assawa is hosting its usual avian assemblage: red-winged blackbirds, Canada geese, ring-necked ducks, a pair of trumpeter swans, and the occasional guest appearance of a common loon or two. Some birds, however, are hard to find and observe, save for their voices.
One such bird that has made a surprise stop at Assawa this spring -- a bird that I haven’t seen or heard since my graduate research days studying avian diversity in North Dakota’s Prairie Pothole Region -- is a favorite of the so-called “secretive species,” the Virginia rail. By all accounts, most rails are more or less secretive in their habits and tend to be more often heard than seen.
Inhabiting dense vegetation such as grasses and cattails typical of many wetlands, along with their diminutive length of just seven to eight inches, it's no wonder the Virginia rail is seldom viewed. But by listening closely and learning the songs and calls of the marsh, one can readily pick out their distinctive calls.
The most common call is identified as metallic sounding and is written as "kid-ick, kid-ick or ticket-ticket." Indeed, once heard you will never forget it.
Like other rails, the Virginia rail escapes danger by running quickly and silently through wetland vegetation. Their thin bodies allow them to do this effortlessly. “Thin as a rail,” as the expression goes, is very fitting. And, like other rails too, the Virginia rail rarely eludes would-be predators by flying. So secretive are these birds that even migration, a time that you would expect ample viewing opportunities, is done under the cover of darkness.
I remember the first time I saw a Virginia rail. While playing my recordings during a wetland survey conducted at nighttime, I was delighted when a rail answered back. Soon after the initial response, the rail began moving closer. After more playbacks, the little fellow, still yapping away, was inside the beam of my flashlight only a few feet away. I could clearly see its long red bill and long legs as it inched cautiously forward.
Another rail, the sora, and even smaller than the Virginia rail, is also one of those secretive species of wetland birds. This odd-looking rail has the appearance of a chicken. Indeed, its short and sturdy bill looks very chicken-like. And, like the Virginia rail, the sora has a powerful and unique voice.
Its call, described as a musical descending whinny (think horse), is really a loud whistle. But with a little effort, you can understand why some imaginative ornithologist long ago thought of a whinnying horse when he heard the sora. Another common whistle is a loud "ker-wee, ker-wee."
Rails, as reclusive as this group of birds can be, are not the only secretive species in the marsh. Pied-billed grebes, American bitterns, least bitterns, and green herons are other shy wetland birds that we seldom see.
The chunky little pied-billed grebe, for example, which has a chicken-like beak similar to the bills of soras and American coots, is also a bird that’s often heard but not seen. A non-gregarious bird with a loon-like call, pied-billed grebes tend to prefer solitude most of the time.
Another secretive bird often found in the same marshes as rails and grebes and other wetland-dependent birds is the American bittern. This long-legged, heron-like bird with cryptic plumage resembling the vertical structure of their cattail and sedge habitats, possesses one of the most unusual vocalizations of any bird. Again, like all the birds mentioned today, American bitterns are more often seen than heard -- they’re mechanical pump-like “onk-a-ronk” call is a one-of-a-kind sound in Nature.
Indeed, many creatures in the animal kingdom rely on dense cover, cryptic bodies, and shy dispositions to avoid being seen. Even so, their secretive ways can be unlocked with a little bit of luck, keen eyes, and listening ears as we get out and enjoy the great outdoors.
Blane Klemek is a Minnesota DNR wildlife manager. He can be reached at firstname.lastname@example.org.