n47_w1150

A few nice cornell birds images I found:

n47_w1150


Image by BioDivLibrary
Dictionnaire classique des sciences naturelles :.
Brussels :Meline, Cans et Ce.,1853..
biodiversitylibrary.org/page/42266269

Tern – Forster’s or Common?


Image by Henry McLin
Atlantic City, New Jersey, May 2006.

From Cornell’s Birds of North America:

"Forster's Tern (S. forsteri) resembles Common when in breeding plumage, but has white underparts, lighter primaries, more black on bill, tail with white outer edges and dark on inner webs of outer feathers…..
Compared to Common Tern, breeding adult Forster's Tern generally much whiter, especially wings and underparts (although immature and worn adult Forster's Tern primaries dark gray), has different tail pattern (Common Tern has whitish tail with dark outer margin), appears long-tailed both in flight and at rest (tail extends well beyond wing-tips on breeding adult Forster's Tern), has longer, stouter, more orangish bill, and longer legs (tarsus length virtually non-overlapping between species)."

The tail looks too short to me for a Forster’s, but the breast looks too white for a Common. Despite the leg size being a good field mark, this photo doesn’t help me.

Tags:n47_w1150