Shush, everyone. You're wading in the marsh. It's summertime, the height of the breeding season for all migrant birds. You're surrounded by tall dense stands of green cattails intermixed with last year's growth. Tiny floating plants -- duckweed -- drift lazily about in the brackish water. The boxed-in sensation you feel is surreal. Indeed, the feeling is the wintertime equivalent of a heavy snowfall in a dense forest.
Lucky was I to walk in such environments during my summers in North Dakota studying bird diversity throughout prairie pothole wetlands. I was interested in learning about those little known species of birds that we rarely see but often hear.
As it were, I called them "secretive species." These were the birds most closely associated with wetland habitats and those that rarely revealed themselves visually. In order for me to detect their presence or absence, I utilized playback techniques to discover their whereabouts.
Through the use of an electronic game-caller and their taped vocalizations played over the machine's loudspeakers, I was able to initiate responses from those little birds of interest time and time again.
My favorite secretive species of bird was 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. As such, the Virginia rail is no exception. Related to cranes and coots, Minnesota is home to three other species of rails: the yellow rail, sora and the king rail.
Inhabiting dense vegetation such as grasses and cattails typical of many wetlands, along with their diminutive length of just 7 to 8 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.
It also amazed me how tiny the bird was. For such a small bird it could sure belt out a tune. So, for a few enjoyable moments, I was able to observe the bird as it continued to vocalize and slink through the vegetation.
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."
Although I attempted to locate an additional, albeit rarer rail, the yellow rail, I have yet to observe this species. Even smaller than the sora at a little over 5 inches in length, the yellow rail, as its name includes, has yellowish plumage, though nothing as bright as, say, an American goldfinch or yellow warbler.
But unlike the unique calls of the Virginia rail and sora, the yellow rail's call is a monotonous series of clicking sounds. If you were to strike steel bearings or a couple of rocks together you would come pretty close in imitating the call of the yellow rail.
Rails, as elusive as they are, 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, the pied-billed grebe tends to prefer solitude most of the time.
Like other grebes, they are swimming and diving birds. Not only will they dive headfirst into the water while they swim, pied-billed grebes will also simply sink downward into the water. Sometimes all you see is the bird's head sticking out above the surface before it vanishes. Its call is loon-like and given in a series.
In order to best survive, many creatures in the animal kingdom rely on dense cover, cryptic bodies and shy dispositions to avoid detection. Even so, anyone of us who understands their secretive ways will be rewarded with many observations -- by sight or sound -- as we get out and enjoy the great outdoors.
Blane Klemek is a wildlife manager with the Minnesota Department of Natural Resources. He can be reached at firstname.lastname@example.org.