Wildlife Viewfinder Guide: Covert distinctions
Mar 30,2007 00:00 by Tim Herd

Preferring a quiet, inconspicuous life, the American bittern stalks the shallow marshes with deliberate caution, relying more on stealth than pursuit in foraging for fish, crayfish, amphibians, rodents and insects. With reed-resembling plumage, the medium-sized heron often freezes in a cryptic, concealing pose with its head and bill upturned.

In the dense vegetation, neither sound nor line of sight travels far, creating a challenge to the solitary birds in breeding season. To reveal both his presence and intentions in early spring, the male arches his back, displays tufts of white feathers on the sides of his neck, inflates his esophagus, and repeatedly broadcasts a far-carrying, low frequency, booming call throughout the day.

Once the partners locate each other, the pair performs an aerial nuptial display before scrabbling together a scanty nest of sticks, sedge or reeds. Concealed in the thick grass, but accessed by two well-beaten pathways, the platform shelters a clutch of three to five buff eggs for about a month. After hatching, the chicks spend several weeks fouling the nest with food debris before fledging and dispersing for distinctively secretive lives.