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