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