Today's prompt for Sunday Stamps is Lunar New Year, and tigers, since the Year of the Tiger starts February 1.
This semi-postal stamp came to mind.
USPS issued first issued it in 2011, and it has been reissued several times. I believe the semi-postal stamps require congressional approval.
Currently this stamp costs 75c, with 17c going to various wildlife conservation funds. For a full list of them you can visit the stamp's page at USPS.