Ticks are parasitic arachnids  that require blood for their development. Adult ticks are easily distinguished from insects based on the number of legs and body regions present. Adult insects have six legs and three major body regions, while adult ticks have eight legs and two major body regions. Visit our  Tick Gallery to see more pictures of ticks. 

Life cycle & habitat: 

Ticks are active year-round in Marin and Sonoma counties. Adult female ticks lay eggs that hatch into six-legged larvae. The larvae develop into eight-legged nymphs and eventually into adults. Typically, each active life stage feeds on a separate host   animal. Ticks are widespread and are commonly encountered by those who spend time outdoors- especially hikers and people with dogs. Adult ticks are commonly found in high grass, while nymphs are found in leaf litter, on logs and wooden benches in natural areas. 

Impact on human health: 
  • Ticks are capable of transmitting a wide variety of protozoan, bacterial, viral and fungal pathogens. For more information about the various diseases that ticks have been known to transmit in California, please visit the California Department of Public Health Tick-Borne Diseases webpage. 
  • Lyme disease is one tick-borne disease of local concern. Click here to learn more about this disease. 
  • The District does not have a chemical control program for ticks, and residents may contract with a private pest control company to incorporate a chemical control program on their property. 
  • For more information on chemical control of ticks and landscaping practices that may reduce tick prevalence, please refer to the Tick Management Handbook.


What you can do to prevent exposure: 

Before entering tick habitat, take the following precautions:

  • Consider applying an effective tick repellent to exposed skin. Click here to use the EPA's repellent search tool. 
  • Consider treating clothes/personal outdoor equipment with an acaricide containing permethrin.
  • Wear light-colored clothing (this makes it easier to spot ticks).
  • Wear long pants, long sleeves, and long socks whenever possible (this makes it more difficult for the tick to get to your skin).

While in tick habitat:

  • Stay on trails (adult ticks are typically more abundant on the uphill sides of trails).
  • Avoid contact with nymph habitat (leaf litter, logs, tree trunks, etc.).
  • Periodically check for ticks on people and animals.

After exiting tick habitat:

Reduce tick abundance around the home:

  • Utilize landscaping techniques that limit cover for ticks near the home, such as removing leaf litter around homes and using gravel or woodchip barriers between lawns and wooded areas (see the Tick Management Handbook for detailed information).
  • If properly timed, application of acaricides (pesticides designed to kill ticks) can be effective in reducing tick populations near homes. Residents should contact a private pest control company if they are interested in this service.



Furman, D.P. & Loomis, C. L. (1984). The Ticks of California (Acari: Ixodida). Berkeley and Los Angeles, CA: University of California Press.

Lane, R.S. (2008). Pest Notes: Lyme Disease in California. Davis: Univ. Calif. Agric. Nat. Res. Publ. 7485.

Mullen. G.R. & L.A. Durden. (2009). Medical and Veterinary Entomology, 2nd ed. Burlington, MA: Academic Press.

Padgett, K. A., & Lane, R. S. (2001). Life Cycle of Ixodes pacificus (Acari: Ixodidae): Timing of Developmental Processes Under Field and Laboratory Conditions. Journal of Medical Entomology, 38(5), 684-693.

Tick-Borne Diseases. (2016). Retrieved September 19, 2016, from http://www.cdph.ca.gov/HEALTHINFO/DISCOND/Pages/TickBorneDiseases.aspx