There is no definitive answer to this question as a variety of animals kill earthworms. Some common predators include moles, shrews, snakes, frogs, and birds. While these are some of the main animals that hunt and eat earthworms, there are many others that also partake in this feast.
Moles are small, burrowing mammals that use their powerful sense of smell to locate earthworms underground. Once found, they will pounce on their prey and devour them whole. Moles typically eat around 50% of their body weight in earthworms each day!
Shrews look similar to mice but are actually more closely related to moles. Like moles, they also have an excellent sense of smell which helps them track down earthworms for a meal. These small carnivores will eat up to 100% of their body weight in food each day - that's a lot of earthworms!
Another common predator of earthworms is the snake. Snakes will often swallow their prey whole, which makes for an easy meal for these reptiles. Some species of snakes that hunt earthworms include garter snakes and blind snakes.
Frogs are another amphibian that love to feast on these slimy creatures. Frogs will often sit and wait near worm holes or other likely places where worms might surface before striking at them with lightning speed. They then gulph down their prey in one swift movement.