red-breasted merganser

bird

Also known as: Mergus serrator, sheldrake

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July 13, 2026

Quick Summary

The red-breasted merganser (Mergus serrator) is a widely distributed diving duck found in Europe and America. It is characterized by a narrow bill with toothlike edges and a hooked tip, adapted for catching fish. Males typically display a reddish breast band that is separated from a green head by a distinct white collar. While mergansers are primarily freshwater birds, they are classified within the sea duck tribe, Mergini. The red-breasted merganser is a ground-nesting species found in northern regions and is sometimes referred to as a sheldrake in the United States.12

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merganser
The somewhat smaller and ground-nesting red-breasted merganser (M. serrator) has a similar range. In the United States, common and red-breasted mergansers are often called sheldrakes (properly a name for the shelducks).
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The somewhat smaller and ground-nesting red-breasted merganser (M. serrator) has a similar range. In the United States, common and red-breasted mergansers are often called sheldrakes (properly a name for the shelducks).
Read More