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