Deer Tick Life Cycle

The deer (or black-legged) tick in the East and the related western black-legged tick are the only known transmitters of Lyme disease in the United States. Both are hard-bodied ticks with a two-year life cycle. Like all species of ticks, deer ticks and their relatives require a blood meal to progress to each successive stage in their life cycles.

The life cycle of the deer tick comprises three growth stages: the larva, nymph and adult. In both the northeastern and mid-western U.S., where Lyme disease has become prevalent, it takes about two years for the tick to hatch from the egg, go through all three stages, reproduce, and then die. Detailed descriptions of this life cycle and the seasonal timing of peak activity, as they occur in these regions, are provided below.