Blackbirds, starlings and magpies normally eat slugs. They can die from eating them because some of the slugs are toxic.
Slugs can eat parsley. Slugs can eat anything, even if it kills it.
Cannibal birds.
Tropical Region Birds and Insectivorous Birds eat butterflies but there might be more birds that eat butterflies.
The "prey"? They don't eat meat, they are herbivores. They eat soft vegetables like carrots, lettuce, and they also like dandelion leaves. If you meant what hunts slugs, frogs hunt slugs. Maybe some types of birds- I dunno.
birds
Raccoons prey on small animals. Included in their prey are insects, grubs, earthworms, crayfish, snails, slugs, fish, frogs, lizards, snakes, birds and small mammals such as mice.
snail and slugs eat garden debris
Although the hedgie eats insects it will eat mice, frogs, small birds, worms, caterpillars, slugs, and toads, as well as plants and fruits. It can also eat small snakes and it has a great liking for eggs. It will eat eggs from the nests of birds.
dersert birds that are higher pedators
They sometimes eat things like mice, and maybe small birds. But they usually eat carrion (dead animals), slugs, snails, and berries.
cats and fox
Slender lorises eat insects, slugs, young leaves, shoots, eggs, flowers, and baby birds.