American Bittern (AMBI)

Botaurus lentiginosus

Adult American Bittern  © Nathan Dubrow / Macaulay Library
Juvenile American Bittern © Nancy Elliot / Macaulay Library


Range

This species’ breeding area spans from the Pacific to Atlantic coasts of the U.S. and Canada. Populations winter in the southern U.S. and Central America, being found from California to Florida down through Panama. They are short distance-migrants that travel through the central U.S.

Additional Maps

Identification

American Bitterns are mid-size herons with stout bodies and necks, long beaks, and short yellow legs. Both male and female adults have brown upperparts flecked with black; their brown and white streaked bellies make them well camouflaged in high-vegetation environments. Adults also have black-tipped wings and white throats bordered by long black stripes. Juvenile American Bitterns have similar plumage but lack the distinctive black throat stripes. 

American Bitterns use low-frequency calls that travel through dense vegetation better than those of higher frequency. During the breeding season, males make resonate three-syllable pump-er-lunk calls that females may respond to with a similar but quieter call. These calls are preceded by a clacking and gulping sound, created when the male inflates his esophagus to make the call. This call will be repeated ten times in succession, serving as both a territorial signal and invitation to potential mates. When flushed, American Bitterns may give a hoarse kok-kok-kok call or nasal haink. Males may also give a chu-peep call when mating. 

Listen to its songs and calls here.

Habitat

American Bitterns breed in freshwater wetlands with tall vegetation. They can be found in wetlands of all sizes but prefer to stay in shallow waters with less dense vegetation where they can best hunt small animals like fish or amphibians. In the wintering season, American Bitterns migrate to bodies of water that don’t freeze (typically near coastlines) occasionally using brackish marshes or even terrestrial areas like grasslands.

Conservation Status 

  • Listed as Decreasing by American Bird Conservancy
  • Listed as Least Concern by BirdLife International
  • Listed as Least Concern by the International Union for Conservation of Nature (IUCN)
  • Listed as Secure by NatureServe Explorer 
Status by State

Threats to Conservation

Due to the reclusive nature of American Bitterns, they are difficult to survey accurately. Their breeding population is estimated to be 2.5 million and population decline across North America has been relatively low. There have been dramatic declines in the Northeast and Midwest of the U.S., which is attributed to habitat loss. More than half of the U.S.’s original wetlands have been destroyed, and inland freshwater wetlands, which are primary nesting sites for American Bittern, are among the most threatened.

Funding Opportunities
General Management Guides
Regional Management Guides
Northeast
Midwest & Central
West
Resources
Works Cited