Game Center achievements

Complete the following tasks to unlock Apple Game Center achievements.

Achievement How to unlock
Bird Saver I You saved 10 Baby Birds!
Bird Saver II You saved 25 Baby Birds!
Bird Saver III You saved 40 Baby Birds!
Bird Saver IV You saved 75 Baby Birds!
Bird Saver IX Save 1,750 Baby Birds
Bird Saver V You saved 125 Baby Birds!
Bird Saver VI You saved 250 Baby Birds! You are awesome!
Bird Saver VII You saved 500 Baby Birds!
Bird Saver VIII Save 1,000 Baby Birds!
Bird Saver X Save 4,000 Baby Birds!