Eagles are predators but they have a very small lifting capacity. Many times I have described our experiments and field observations on what eagles can lift.
Generally a male can lift about 1.5 pounds and a female up to 2.5 to 3 pounds -- the latter if there is a good headwind. However, this is not even lifting this weight for more than a few 100 yards and not necessarily up to a nest.
On the other hand, many a small cat, or parts of a road killed cat, can be lifted. Eagles have great difficulty handling mink or cats because of 'fighting back' with sharp claws. So a big 8 -10 pound cat is certainly beyond a bald eagle's capacity but parts of one, particularly cut by vehicle traffic, can and are lifted.
We have the same frequent problem here but the predator is the coyote -- some live almost exclusively on cats. Raccoons take cats but a big cat can out-climb and out-fight or out-run most coons.
As you probably know cars take most cats. I and a few close neighbors lose one or two of our barn cats each year. We see them dead on the road or their blood smear left when the coyotes got to them before I could even throw them off the road or bury them. I recently wrote an item about road kills -- and the good source of food they are for eagles. However, the other side is that eagles are often killed eating road kills and I spend a lot of time throwing kills off the road for this purpose.
Hancock Wildlife Foundation