Male American Bitterns Calling
American Bitterns typically nest in tall, standing cattails, rushes and sedges, where they are well concealed. Like most birds, male bitterns use their voice to attract a female and to stake out their territory. Dense marshes present a challenge when it comes to being heard, however. American Bitterns overcome this challenge by having a very low-frequency call, which is audible at great distances in dense marsh vegetation. Once you’ve heard a bittern’s call, you’ll never forget it. It is very deep, and has three syllables – “oong-ka-choonk” – which are preceded by clicks and gulps. The bittern makes this call multiple times by inflating his esophagus while contorting himself quite violently. A female American Bittern couldn’t help but be impressed. (You can hear a bittern calling by visiting Cornell’s site, http://www.allaboutbirds.org/guide/american_bittern/sounds .
American Bittern
American Bitterns have returned to New England from their southern wintering grounds, and are announcing their presence with a unique song that Sibley describes as a “deep, gulping, pounding BLOONK-Adoonk” that they repeat over and over. These secret, well-camouflaged marsh birds are almost invisible as they slowly walk through marsh grasses. When they stand still and point their bill skyward, they are easily mistaken for the reeds they inhabit.
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