Here is the full list of all 43 Save the Dodos achievements.
Reach 50 defeats
Reach 25 defeats
Win 300 stars
Clear 100 levels
Reach 1500000 points overall
Kill 5 dodos at the same time
Accelerate time more than 25s
Complete 35 achievements
Keep a tile pressed more than 25s
Play a level more than 25 times
Play a level more than 10 times
Save 5 dodos at the same time
Reach 1000000 points overall
Do nothing during more than 60s
Win 150 stars
Clear 60 levels
Do nothing during more than 30s
Lose a dodo next to an exit
Get more than 3 special dodos
Save 200 dodos
Reach 500000 points overall
Kill 100 dodos
Complete 20 achievements
Reach 10 defeats
Move 15 tiles in less than 5s
Move 10 tiles in less than 5s
Get more than 2 special dodos
Kill 50 dodos
Clear 25 levels
Move 5 tiles in less than 5s
Win 50 stars
Save 100 dodos
Complete 10 achievements
Get more than 1 special dodos
Lose in less than 20s
Kill 20 dodos
Play a level more than 5 times
Lose a dodo in less than 1s
Save a dodo narrowly
Save 50 dodos
Clear a level in less than 20s
Clear a level in less than 15s
Clear a level in less than 25s