American Dog Tick
Dermacentor variabilis
Moderate Risk Risk
Known to transmit: Rocky Mountain spotted fever, Tularemia
2
Total reports
1
Reports this week
About
One of the most commonly encountered ticks in the US. Larger than deer ticks and easier to spot. Prefers dogs but will bite humans. Found along trails, roadsides, and grassy areas.
Appearance
Brown with white/silver mottled markings on the back
Size
Adult female: 5mm unfed, up to 15mm engorged
Habitat & Range
Habitat
Grassy fields, roadsides, trail edges, meadows with low vegetation
Region
Eastern two-thirds of the US and Pacific coast
Peak Season
April–August
Life Stages
Larva (< 1mm)
Six legs. Feeds on small rodents.
Nymph (1–2mm)
Rarely bites humans.
Adult Female (5mm)
Brown with silvery-white ornate markings.
Adult Male (3.5mm)
Heavily mottled silver/white pattern.
Safety Tips
- 1.Larger and easier to spot than deer ticks
- 2.Most active in spring and summer
- 3.Common on dogs — check your pet after walks
- 4.Rocky Mountain spotted fever requires prompt treatment — see a doctor if you develop fever and rash