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least tern

least tern (Sternula antillarum) [state and federally endangered]
Photo © Alan Murphy Photography

Features and Behaviors

The least tern is about nine inches in length. The yellow legs, yellow feet and white forehead patch are distinctive. The bill in breeding birds is yellow with a black tip. There is a black edge to the outer wings. Nonbreeding and immature birds have a dark bill.

The least tern is an uncommon migrant and rare summer resident in southern Illinois. It may occasionally be seen as a migrant or wandering individual in northern Illinois. Migration: Spring migrants begin arriving in mid-May. Fall migration starts in early September. This species winters in South America.The preferred habitat includes rivers and lakes with sandbars or sand islands where it feeds on fishes, insects and other aquatic macroinvertebrates.

Reasons for Concern

This species prefers to nest on sandbars or sand islands, habitats that are rare and vulnerable to flooding, dredging, dumping and human disturbance.

Illinois Range


​Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Charadriiformes
Family: Laridae

Illinois Status: state and federally endangered, native