Common and/or Forster's Tern? - May 24, 2024 on Georgian Bay, Ontario (1 Viewer)

[osbirder]

I have photos of 2 or 3 terns taken on May 24, 2024 on Georgian Bay. Which species are these?

 

[Southern Viking]

All are Forster's IMO. The upper loral area seems to have a narrower white area than I'd expect on the left hand bird in the first shot, but they all have the silvery outer primaries

 

[Montereyman]

I have found that Merlin can identify the four tern species in my area from their calls. Helps when they are flying high overhead and not easily viewed with binoculars.