Crossley Bird ID Guides

Crossley ID Guides
  • Home
  • Bird ID Guide
  • Events
  • Videos
  • Books
  • Recommendations
    • Birder Gift Guide
    • Birding Optics
    • Photography Gear
  • About
    • Contact Richard Crossley
Forster's Tern
Sterna forsteri
Forster's Tern Sterna forsteri
FOTE

Bird Description

The most common tern in many areas. Breeds in freshwater marshes and is widespread on migration. The only wintering tern in many areas (mostly coastal). Hovers and dives for fish, often in concentrated or mixed flocks. Fond of perching on posts. ID: Variable patterns of color make ID tricky. Subtle but noticeable differences in shape. Compared to COTE is slightly larger, bigger-billed, longer-legged, flatter-headed, thicker- and longer-necked with a less rounded undercarriage. Difference in shape shows better in flight, particularly flat undercarriage. Wings broader-based and less angled. A more powerful look overall! Pale. Distinctive with dark mask in most plumages. Ad br: black cap extends down nape. Bill more orange than in COTE but can be difficult to judge. Upperparts paler gray with distinctive whitish flight feathers but these wear dark through the summer making this field character inconsistent. In flight, the contrast between whiter outerwing and gray innerwing coverts forms striking pale area even at great distance. Very long tail streamers that wear shorter through summer. White underparts (grayish in COTE) also obvious in flight. Nonbr: cap becomes a diagnostic black eye patch by late summer, also in young birds. Dark bill. Molts outer primaries in summer. 1st-year: as nonbr with dark tertials. Juv: ginger-brown feather centers, particularly on back, forming dark 'saddle.' Wear/molt through fall to gray appearance but retains a few worn juv feathers, but all still have diagnostic eye patch.


Share this:

  • Facebook
  • LinkedIn
  • Twitter
  • Tumblr
  • Pinterest

Find Photos, Descriptions, Range Maps, and More in These Crossley ID Guides


Gear Guides
Nikon AF-S FX NIKKOR 18-35mm f/3.5-4.5G ED Zoom Lens
Birder Gift Guide
Perky-Pet Window Mount Hummingbird
R4B
Race 4 Birds is a foundation created by Richard Crossley, Tim Keyes, and Connie Campanella to promote youth birding competitions. Please check us out and "join the chase" at www.Race4Birds.org
Pledge to Fledge today!
Hawk Mountain
It was my honor to sit on the board at Hawk Mountain Sanctuary. They are pioneers in many areas of research, education and conservation. Visit them at www.HawkMountain.org.

Richard Crossley

Avatar photoRichard Crossley is an internationally acclaimed birder and photographer who has been birding since age 7. His love of the outdoors and his interest in teaching, design, and technology have shaped his unique vision for the future of birding and bird books. He lives with his wife and two daughters in Cape May, New Jersey. Read More…

Copyright © 2025 Richard Crossley · All Rights Reserved