Bob,
 
To be honest, I did not get a good fix on the tail shape -- all I noted was  
"forked."  I was busy trying to get a good look at the underwings (no  
extensive dark primaries were noted), shape and color of the bill (a substantial  and 
fairly long bill but not as deep or prominent as that of the Caspian I  
thought and more to the orange end of the spectrum rather than bright  red/orange) 
and sorting out the apparently all black cap -- something I've  personally 
seen only a couple of times on the ROTE.  There were a  few first winter 
Ring-billed Gulls flying around at the same time and  it took me a few seconds to note 
the thinner, longer wings and the downward  pointing bill posture of the two 
terns as they flew in and their more  leisurely wingbeats as compared to a 
Forster's.  They struck me as being  near the size of the Ring-bills but more 
streamlined.  The underbody was  bright white and the upperparts uniform light 
gray.  I noted no markings or  colors that would lead me to think it was a 
juvenile bird.  I waited for  half an hour but they did not return from their one 
pass.  It was about  11:15 a.m. with a fairly bright sky and I had them in view 
for about 45  seconds.  They did not call.
 
I realize that bill color can be quite variable in the terns, so I guess my  
id rests pretty much on my impression of bill size and the lack of dark  
underwing primaries to separate it from the Caspian Tern.  That and  "jiz".  I've 
always felt the Caspian was a deeper-breasted,  chunkier-looking bird than the 
Royal.  Of course it gets really problematic  if I start thinking of Elegant 
Tern.  If I'd seen these birds along the  south-central California coast I'd 
have called them Elegants in a second but for  a bill that was just not 
"stiletto-like" enough for that species.
 
I'd appreciate any help you can offer me in any future encounters with  the 
Royal tern in breeding plumage and what I should have tried to observe  in this 
sighting.  Terns are hell.
 
Lou
 
Louis Nielsen  
Reisterstown,  MD