Bird Guide › Common Loon

How to Identify aCommon Loon

Gavia immer · 26–36 in (66–91 cm)

Male vs. female

Male

Black head with a green sheen, a striped neck collar, and a back checkered in black and white squares. Sexes look alike.

Female

Identical to the male in the field, though usually smaller.

Male photo: John Picken from Chicago, USA / Wikimedia, CC BY 2.0 · Second photo: ADJ82 / Wikimedia, CC BY 4.0

Quick ID

A heavy-bodied diving bird with a dagger bill — in summer checkered black and white with a glossy black head.

Field marks

Heavy straight dagger-shaped bill held level
Checkerboard black-and-white back in summer
Sits very low in the water
Plain gray above and white below in winter

Similar species

Double-crested Cormorant — Has a hooked bill held tilted upward and an orange throat patch.

Canada Goose — Grazes on land, with a stubby bill and a white cheek strap.

What it sounds like

A long mournful wail, a laughing tremolo, and a complex rising yodel given only by males.

Behaviour that gives it away

Its bones are denser than most birds’, which reduces buoyancy for diving but means it needs a long running start across water to take off.

Habitat & range

Clear northern lakes in summer; coastal waters and large ice-free lakes in winter.

When you'll see it

Depending on where in North America you are, it is a summer visitor that arrives to breed, a winter visitor and a passage migrant, seen mainly in spring and autumn.

What it eats

Fish caught in underwater pursuit, plus crayfish and other aquatic animals.

Did you know?

Unlike most birds it has solid rather than hollow bones, which helps it dive but means it must patter across the surface for many yards to get airborne.