Tern sp., Laguna de Terminos, Campeche, Mexico, February 2023 (1 Viewer)

[Bitis]

I saw this large Tern on February 22nd 2023 in Laguna de Terminos, Campeche, Mexico. There were also a lot of Royal Terns. This Tern had a orange/reddish bill though, not yellow like the Royal Terns. Top of the head was also more solid black and black markings on underwing also were different (large black area, not just black trailing edge like in Royal Tern). Is it a Caspian Tern?
All photos show the same individual. Last two photos in direct comparison with Royal Tern.
Thank you!

 

[Butty]

Yes. Dark underside to primaries.

 

[Bitis]

Yes. Dark underside to primaries.

Thank you, Caspian Tern is a Lifer for me