What is a tick?

Ticks are small, spider-like creatures. They feed on the blood of birds and mammals. They can be between 1 mm and 1 cm long and have 6 or 8 legs (depending on their life stage).  There are lots of different types of tick and they are found all over the world.

Ticks can look different depending on their species, stage of their lifecycle or how recently they have fed. The diagrams below show some of these differences and a size comparison to the average fingernail.

Image sources:

 About Ticks | Lyme Disease Action                                                An in-depth guide to Ticks in Scotland (2024)