Full list of all 11 Bird Game + achievements worth 1,000 gamerscore. It takes around 1-2 hours to unlock all of the achievements on Xbox One.
Reach a score of 200 on endless mode
Reach a score of 100 on endless mode
Reach a score of 50 on endless mode
Reach a score of 150 on endless mode
Complete a level in Dark Mode
Reach to the second boss fight
Catch a fish
Defeat the Bug Bros
Reach to the first boss fight
Recover some health with the collectables
Get a speed boost