Loons and Other Waterbirds: How Do You Tell Them Apart?

Other birds on lakes in summer may be mistaken for loons. One species that is often confused with a loon is the Common Merganser, but there are several field marks that distinguish them from loons.

ADULTS

Adult Common Loon (male or female)


Photo: Kittie Wilson

Male Common Merganser


Photo: John Rockwood

Juvenile loons (chicks older than 8-weeks of age or 2nd year birds that occasionally summer on lakes) can be mistaken for a female common merganser.

Juvenile Loon (male or female)


Photo: Kittie Wilson

Female Common Merganser


Photo: John Rockwood

Another diving, fish-eating bird that is sometimes mistaken for a loon is the Double-crested Cormorant. Cormorants have slender bodies with a long neck and hooked bill with an orange patch at the base. They are often seen standing on docks, rocks, or buoys with wings outstretched to dry.

Common Loon


Photo: Kittie Wilson

Double-crested Cormorant


Photo: Kittie Wilson

Common Loon


Photo: Brian Reilly

Double-crested Cormorant


Photo: Kittie Wilson

Another waterbird that is sometimes confused with a loon is the Canada Goose. The long black neck, white cheek patch, and wide, flat bill are good distinguishing characteristics of geese.

Common Loon


Photo: Kittie Wilson

Canada Goose


Photo: Brian Reilly

Common Loon


Photo: Brian Reilly

Canada Geese


Photo: Kittie Wilson

BIRDS WITH CHICKS

Common Mergansers have up to 17 ducklings who are sometimes seen riding on the female's back, but they are lighter in color than loon chicks and have a reddish crown. Common Loons have 1-2 chicks. Loon chicks change in color from almost black to light brown to grey as they grow. Scroll to the bottom of the page to see the loon chick stages. Merganser broods can be reduced to 2 chicks or fewer due to predation.

Common Loon


Photo: Kittie Wilson

Female Common Merganser


Photo: Brian Reilly

Canada Geese have from 2-8 goslings that are yellow & brown when young (unlike loon chicks that are very dark) and they do not ride on a parent's back. In New Hampshire, they nest earlier than loons, so most Canada Goose chicks have already hatched by late spring. Young goslings are also susceptible to predation (like merganser ducklings), so a brood may be reduced to one or two chicks rather quickly.

Common Loon


Photo: Kittie Wilson

Canada Goose


Photo: Brian Reilly

LOON CHICKS

Less than one week old


Photo: Kittie Wilson

Two weeks old


Photo: Kittie Wilson

Five weeks old


Photo: Kittie Wilson

Eight weeks old


Photo: Kittie Wilson

Ten weeks old


Photo: Kittie Wilson