Swaying in the breeze, the reeds of Colorado’s wetlands offer a serene sight for city-spoiled eyes. Listening closely, a symphony of violins and woodwinds seem to rise out of the cattails as the wind runs through them. Nearby, shorebirds are visible, their long beaks dabbling in the shallow water and scooping up unlucky fish. Everything is as you’ve seen it before, until suddenly you hear a distinct “
oong-KA-chunk” or “
kok kok kok” booming out from the cattails. Knocking you out of your meditation, you scan the grasses looking to see what could have made this very different, percussive call. After seeing nothing but reeds swaying in the wind, you sit there puzzled, feeling discouraged at your birding abilities. Well, fret not fellow birder, you just had an encounter with an elusive, heron-like shorebird that prides itself in its camouflaging abilities—the American bittern.
The American bittern is a stout, heron-like wading bird. It measures 24-33 inches, and has brown/buff upperparts with a brown/streaked belly. Although it looks similar to other herons, what makes this bird distinct is its ability to camouflage. Most herons will flush, or flee, when approached. The American bittern, on the other hand, prefers to stay put and fool the intruder into thinking that it’s just another reed swaying in the wind. When threatened, this bird stretches up its neck, points its bill to the sky, and starts waving side to side, almost in unison with the surrounding vegetation. This can make the bird quite tricky to view, but the challenge makes the sighting that much more enjoyable.
After hearing their calls in the wild, you’ll understand why American bitterns have earned the nicknames “thunder pumpers”, “stake-drivers”, and “mire-drums”. They use these booming calls to communicate with each other. Although typically an asocial bird, mating brings pairs of bitterns together into what’s usually a monogamous relationship. Pairs form in May after the females arrive at the nesting site. The nest is hidden in dense vegetation, and stands in water that’s typically 4-5 cm deep. They build their nests from the surrounding vegetation: cattails, reeds, sedges, etc. Egg laying is performed daily, with one egg being laid in the morning until the full clutch is laid, usually 2-7 eggs total. The female does all of the brooding and feeding, while the male contributes by guarding the nest.
As a wading bird, the American bittern relies on the food that its wetland habitat has to offer. It munches on insects, amphibians, crayfish, other small fish, and even small mammals. Wetland habitat, however, is slowly disappearing. Habitat loss and reduced habitat quality has been a threat to the American bittern, and already their numbers are declining. The US Fish and Wildlife Service listed the bittern as a Species of Management Concern in 1982 and 1987, and some states list it as a Species of Concern. Through wetland management practices, we can help keep the American bittern swaying like grasses in the wind. The symphony of reeds in our wetlands isn’t complete without a little bit of percussion.