Cows, Horses, Pigs or Dogs. I'm sure one of those would send a strong message...
I've got to go with the duck billed platypus. We'll freak.
Humans already care.
The animals people most like to eat, will not be going extinct anytime soon of course, and are not in danger of it. Bees? That doesn't seem to concern the masses very much, that fact that they are dying off due to pesticides.
I don't have a good or clever answer to this question.
As long as humans are around, farm animals will never become extinct. Even fish, they'll just clone them. They might even clone bees too.
Hopefully the damn snakes!