Little duckies lost.
Ingame stamp description:
Ducks in a Row: In Free Practice Mode, find all the stray ducklings on the lake and lead them back to their mother. You have to complete the Speed Challenge afterwards to get the stamp.
Strategy:
If you bump into anything, you lose any ducks following you. I did them all in one go to look cool, but you're allowed to play it safe and deliver one at a time or whatever.
Difficulty: 2/5
Wii Sports Resort All Stamps Playlist:
• Wii Sports Resort (Wii) | All Stamps