I spent last Sunday on a long and unsuccessful search for an American bittern. I looked in four different places in four counties but couldn't come up with one.
The American bittern has been a favorite of mine ever since the first spring I got serious about birding, when I saw four in Lincoln Park. I thought they were just everyday birds, an impression that was strengthened by the pair that nested that summer on some land my wife and I owned in Wisconsin. We used to lie in our tent in the early morning and listen to the male bittern produce a deep, resonant, gulping sound like no other sound in the animal kingdom.
I could write it as gump-galump or oonk-ka-gonk, silly phrases that convey the rhythm but not much else, or I could make the traditional comparison to the sound of an old-fashioned mechanical pump, a comparison that will be meaningless to many.
The call most resembles a sound effect from a Warner Brothers cartoon. Imagine Bugs Bunny being chased by a huge monster. Somehow Bugs tricks the monster into swallowing an enormous boulder. The bittern's call is the sound of the monster swallowing the rock.
Marshes are the preferred nesting habitat of the American bittern, which will tell you something about my skill in buying real estate in Wisconsin. The original bittern is a European bird that gets the name with no qualifying adjectives. Bitterns differ from other herons in being somewhat shorter legged and shorter necked. They make their necks look even shorter with their habitual hunched-over stance--the posture of someone "shouldering some heavy responsibility, oppressed with a secret, or laboring in the solution of a problem of vital consequence," wrote Elliott Coues, one of the founding fathers of American ornithology.
However oppressed they may appear, bitterns are big birds: two and a half feet long, with a wingspan of more than four feet. Their plumage is dark brown flecked with light brown on top and white flecked with brown below. Their beaks are the long, slender daggers typical of herons.
If you flush a bittern, it will leap awkwardly into the air, squawking raucously and shitting a furious stream of white liquid feces--chalk is the accepted euphemism--that presumably helps discourage predators who get too close.
Despite the unusual run of luck I had in my first spring of birding, the American bittern is not a common species, although it once was. It is on the endangered list in Illinois for the customary reason: habitat loss. Its numbers have declined with the destruction of our marshes.
Herons hunt by stealth, and the bittern may be the stealthiest of the lot. It spends most of its hunting time standing absolutely still. When it moves, it moves one leg at a time--very slowly. It sets down the moving leg and slowly picks up the other one. It sees a frog in the water and almost imperceptibly extends its neck toward its quarry. And then strikes, clasping the prey in its beak. If the catch is small, it will swallow it whole. Larger animals get beaten, banged, and gummed to make them soft enough to swallow.
Bitterns will eat almost anything they can get their mandibles around. Frogs, catfish, sticklebacks, small eels, pickerel, killifish, garter snakes, water snakes, salamanders, crayfish, water scorpions, giant water bugs, diving beetles, dragonflies, and others too numerous to mention are all a part of their diet. They also eat meadow mice that drift too far into the cattails.
Flying away is the bittern's last line of defense. It much prefers hiding out as a means of avoiding trouble, and it has its own unique style of vanishing into the background. A hiding bittern stands with its beak pointed straight in the air, its neck extended, and its body compressed. The effect is of a long, slender, vertical stalk with a small lump at the bottom. You could easily mistake it for a stump or the remains of last year's cattails. Sober observers have even reported that bitterns hiding in a patch of cattails sway in the breeze to match the actions of the leaves around them.
Bitterns try to keep their breasts toward the threat they are hiding from, so if you happen to see past the camouflage, you will be looking at the breast, the front of the throat, and the underside of the beak. You might think a bird in this position would be vulnerable, but the bittern's eyes take care of that problem. The eyes are set low on the side of the head. They look around the upturned beak and right at you with a furious glare. It's very unsettling. You're sure it's a face, but you don't know where the parts are. You expect to see some sort of mouth in the middle of the animal's throat.
The larger herons--great blues, great egrets--hunt in open water. Bitterns live and hunt right in the middle of the cattails. Their habits are very much like those of the rails, an unrelated group of birds occupying a similar habitat. They are solitary, quiet, cryptically colored, unobtrusive. Like rails, bitterns can scrunch themselves up--not a very scientific description, but accurate--and slip through tiny openings with ease. Audubon had a captive least bittern, a smaller relative, with a body that was two and a quarter inches wide when the bird was relaxed. Scrunched, the bird could slip between a pair of bookends set just one inch apart. A bittern whose biding strategy fails can fly a short distance, drop down into the cattails, and then run 50 feet without stirring a leaf.
Mating among the bitterns is accomplished after elaborate courtship rituals. Courting birds display large white ruffs around their necks, plumage that is not visible at any other time.
They build their nests in the cattails, weaving low platforms just a few inches above the water. The females apparently do all the incubating. The babies are able to move around immediately after birth, and they leave the nest within two weeks. They adopt the beak-in-the-air posture for protection while they are still in the nest.
The bittern's present status as an endangered bird is an indication of the sorry state of American wildlife. We might expect birds like the peregrine falcon to be in trouble. This is a bird that was scarce even when eastern North America was a wilderness. But once upon a time, bitterns nested in every pothole marsh and every streamside cattail patch from British Columbia to Newfoundland and from Florida to California. It is grotesque to think that they are now endangered.