This pack of 6 cards features 6 different species of hummingbirds. These groups are from the "Hummingbirds of North America" identification guide I made for the FeederWatch Program at Cornell Lab of Ornithology. Each grouping shows an adult male, adult female, and juvenile bird with key identification field marks shown. The original watercolors reproduced beautifully in these digital cards. Packs make great gifts for hummingbird lovers. Or use the blank space inside to drop a line to a friend.