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Least Bittern

Ixobrychus exilis


The smallest member of the bittern family is about 14 inches long and has a wingspan of about 18 inches.

Least Bittern

One of most camouglaged members of its family, the least bittern is generally buff on the underside and brown on the upperside, with a white chin, throat, foreneck, and belly. Its most conspicuous features are large buff-to-chestnut-colored wing patches. The bill is thin and yellow, as is the iris of the eye. It has short legs that are green on the front and yellow behind, short outer toes, and long, curved toenails that allow it grasp onto vegetation. Both sexes are similar in size, but the female's back is purple-chestnut in color while the male has an almost black back. Juvenile coloration is similar to that of females, but the crown is paler and brown and the breast and throat have heavier streaking.

Distribution and Habitat

The least bittern lives in dense, weedy marshes and sloughs.

It summers throughout most of the eastern United States, and in scattered locations in the West, and winters in the extreme southern United States, through Mexico and Central America into parts of South America. It migrates south from late August through September, and returns from early April to late May, depending on latitude.


The least bittern feeds primarily on small fish and large insects, along with some crustaceans, amphibians, small rodents, and small snakes.


Mating occurs in June and July. There appears to be some competition between males for mates, but the extent of that competition is not known.

The nest is a mall platform of drief plant material located on sturdy vegetation 8-14 inches above the water.

The 2-7 pale blue or greenish eggs hatch in about 20 days.

Habits and Behaviors

A very secretive bird, a least bittern will not come out of hiding even if disturbed. When alarmed it freezes, with its neck taut and bill pointed straight up,

Although a member of the "wading birds order," the least bittern prefers to use its long toes to walk around on the vegetation just above the water's surface and is seldom seen walking in the water itself.

Least bitterns have a varied repertoire of calls.

Scientific Classification

phylum Chordata
subphylum Vertebrata
class Aves
order Ciconiiformes
family Ardeidae
genus & species Ixobrychus exilis

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The Robinson Library >> Science >> Zoology >> Birds >> Order Ciconiiformes

This page was last updated on March 22, 2018.