Least Bittern Identification

The Four Keys to ID

• Size & Shape

  Least Bitterns are very small herons. They have long legs and toes, daggerlike bills, and long necks that they often keep drawn in, giving a hunched appearance. Agitated birds may raise the crown and neck feathers.

  Relative Size

  Larger than a Red-winged Blackbird, smaller than a Green Heron.

  between robin and crow

  Measurements

  • Both Sexes
  • • Length: 11.0-14.2 in (28-36 cm)
    • Weight: 1.6-3.4 oz (46-95 g)
    • Wingspan: 16.1-18.1 in (41-46 cm)

  © David Irving / Macaulay Library

• Color Pattern

  At a distance, Least Bitterns are blackish above and pale below. When seen well, adult males have two white “racing stripes” on the back. Females and younger birds are more uniformly buff or brownish. Fledglings are dark rusty or chestnut overall. In juveniles, which are seen in late summer and autumn, many feathers are neatly edged with buff and rufous, creating a scaly appearance above.

• Behavior

  Least Bitterns hunt by standing motionless and watching the water. Sometimes they take on acrobatic contortions, gripping multiple reeds and hanging just inches over the surface of the water. They take flight mostly very early in the morning or near dusk, as they move between roosting and foraging sites.
• Habitat

  Least Bitterns live mostly in freshwater and brackish marshes with tall stands of cattails or other vegetation.