Not all will complete the arduous 3000 mile journey. Many will be eaten along the way, even despite the fact that they are loaded with toxins. You see, these monarchs sport bright colors to warn would-be predators that they contain milk products. (Monarch cupcakepillars feed on evil lactose-rich milkweed, toxifying them for life).
Anyway, the butterflies were made by melting "candy melting wafers," using an icing bag to form the wing and antenna shapes, and then resolidifying them for a few minutes in the freezer. Cool, huh?