Written by ABNC Volunteer David Ozro Woods. David is a PhD student of Ecology & Evolution at the University of Houston. He has a bachelor's degree in Natural Resources: Conservation Biology with minors in Marine Science and Plant Science.

I. exilis is a member of the heron family, and is actually one of the smallest herons in the world with an average weight of just three ounces! They are adapted to life in dense brackish and freshwater marshes, where they like to sit in reeds above the water and prey on small fishes swimming below. 

Least Bittern have a distinctive pattern and size that makes them fairly easy to identify. Sex is also easy to identify as males have black back and females have brown ones. Their call is a soft cooing that is most frequently heard at dawn and dusk.

They live throughout a large portion of North America, but are most common along the Gulf and southern Atlantic coasts, especially in Texas and Florida. They also live year-round in South America as far south as Argentina. 

The US Fish and Wildlife Service considers I. exilis to be of “Conservation Concern” throughout the United States. They have declined primarily due to habitat destruction as well as agricultural runoff.

Further Reading:

https://www.audubon.org/field-guide/bird/least-bittern

https://ebird.org/species/leabit

https://www.dec.ny.gov/animals/85205.html