CASPIAN VS ROYAL TERN, GOODLAND, MARCO ISLAND, FL

   On a sandbar off of Goodland we sighted quite a few terns.  They seemed to be a mixture of Caspian Terns and Royal Terns.  The two species of terns are difficult to tell apart, particularly when they are in breeding plumage.  Here's how we differentiated them:

• The tern in the first photo is a breeding Caspian Term - it has a more reddish bill with a dark tip.  Also the black cap lays flat.
• The tern in the second photo is a breeding Royal Tern - it has a more orangish bill and no dark tip.  Also, if you look closely you can see that the black cap slightly swoops back.
• The tern in the third photo is a nonbreeding Caspian Tern - Again it has a more reddish bill with a dark tip.  It is nonbreeding because it has a dusky forehead, rather than a completely black head and forehead of the breeding Caspian Tern.