I recently transplanted some kale plants to a new spot in my garden. They had been doing well for 2 weeks when I noticed something was eating them to the stalk. I have included 2 pictures. On the back of leaf pic I notice white flies but I've never seen white flies eat a plant like that. We also have feral cats that live in our yard and the occasional possum looking for cat food. Any help would be appreciated.
Holes that big would be made by flea beetles or caterpillars (the defoliated leaves especially.) Late in the growing season many pests are already established in the garden and many are in their larger stages so they eat more, so they have to be expected. Next year, we'd recommend that cover your kale with row cover as soon as you plant it to preempt these pests.
There are individual profiles on flea beetle and caterpillars in our Grow It Eat It section > Vegetables under Common Problems > Insect Pests.
Feral cats and opossums: Cat food is going to attract these animals. If you do not want them around, the cat food can only be put out for short periods during daylight hours, or when your cat is eating. Both can be trapped but you'll need to make arrangements with an animal rescue Here is our info on nuisance animals: http://extension.umd.edu/hgic/best-practices-nuisance-wildlife
and opossums: http://extension.umd.edu/hgic/opossums
and feral cats: http://extension.umd.edu/hgic/domestic-and-feral-cats