Ticks drink blood

Ticks feed on warm-blooded animals, such as dogs and humans. They often wait for their victims in tall grasses or shrubs.
Ticks attach to the body of their new victim with their strong jaws, and begin sucking blood. Ticks use this blood as their food. When a tick has sucked itself full of blood, its belly takes on a ball-like shape.
A tickbite should be avoided, because some ticks spread diseases that are harmful to humans. This is why one should always check their skin and clothes for fleas after going for a hike in nature.