According To Google Translate...

...this is 'thank you' in bird-speak.

He is referring to all of the love you shared with me on yesterday's seven year blip anniversary.  The stars and faves were icing on the cake.  The special part was having shared the day with so many who mean so much.  xx

Key to the 2555 collage:
2011-2013-2016
          2014
2012-2015-2017