Many species of ticks inhabit the Columbia Basin.
©1997 by Roger Drummond, from Ticks and What You Can Do About Them, published by Wilderness Press.
What is a tick?
A tick is not an insect. Ticks have eight jointed legs and are related to spiders, scorpions, and mites in the class of arachnids. Because ticks depend on a host for survival, they are parasites. About 800 kinds of ticks exist in the world, and about 100 of these are known to carry diseases. Five kinds of disease-carrying ticks live in Washington State. They include the Rocky Mountain wood tick (carries tick paralysis), American dog tick (carries Rocky Mountain spotted fever and tick paralysis), the western black-legged tick (carries Lyme disease), and the brown dog tick (non-disease carrying). Relapsing fever ticks also are known to reside in our state.
What does a tick look like?
The ticks you are likely to encounter have a hard, smooth shield that covers all or part of their body. They range in size from about one-quarter inch to about the size of the head of a pin. Like other arachnids, ticks have two main body parts, a head and an abdomen. A tick's head is so tiny compared to its abdomen, the creature looks like a body with eight curved legs. The front two pair of legs curve toward the tick's head, and the back two pair curve toward the abdomen. The life cycle of a tick involves four stages, egg, larvae, nymph, and adult. Adult female ticks are generally larger and more colorful than adult male ticks, but after laying eggs on the ground in vegetation, the female tick dies. Males live on to mate with other female ticks.
Where do ticks live?
Most ticks "hang out" on vegetation such as plants, trees, weeds, or grass in wooded areas. Generally, ticks are found where they are most likely to come in contact with animals- near streams, lakes, or by a path animals are known to travel daily for food or water. Some ticks also are found in nests, burrows, and places where their animal hosts live and sleep.
How do ticks attach to a host?
A tick's only source of nourishment is the blood it sucks from animals. Ticks really don't "bite" their hosts. Upon successfully boarding an animal host, the tick finds a place to attach itself and imbeds its barbed mouthparts into the host's skin, which makes it difficult, but not impossible, to remove the tick. The tick's sharp mouth parts then pierce tiny blood vessels. Like vampire bats, ticks have an anticoagulant in their saliva to keep the blood of their host from clotting while it feeds. A tick's saliva may contain diseases, thereby transmitting disease organisms to the unknowing host. Most animals (including people) do not feel the tick imbedding itself into their skin, or even feel it sucking their blood. If left undetected over 2-4 days, the tick will engorge itself with the blood of its host and simply drop off. Most ticks feed and then molt to the next stage in their life cycle. Not all ticks that come in contact with animals carry disease.
"Science is constructed of facts as a house is of stones. But a collection of facts is no more a science than a heap of stones is a house." Henri Poincare
Keep in mind this fact sheet is intended to be used only as background information to support your effort to encourage inquiry-based science, which parallels the way scientists uncover knowledge and solve problems.
Protecting Yourself From Ticks
If you plan to be in a wooded area, wear light-colored clothing that makes it easier to spot a tick that may have crawled on you. Avoid coming in contact with vegetation where ticks may be waiting for a host. Wear long pants tucked inside your socks. Spray the outside of your clothing and shoes with an insect repellent containing DEET.
When you return home, carefully check your clothes and launder them using hot water to kill any hidden ticks. This will prevent any ticks you may have inadvertently brought home with you from getting loose in your house and possibly finding a meal on a family member or a pet. Remember, it takes several hours for a tick to attach itself to your body. Taking a shower with a scrubber or washcloth will remove any ticks you may possibly have on you. If you find a tick attached to your body, remove it promptly. Grab the tick as close to your skin as possible. A pair of tweezers is helpful. Pull firmly without twisting or squeezing the tick. The tick will release its mouthparts from your skin with persistent tugging. After the tick is removed, apply an antibacterial ointment to the attachment site.
Although you may be tempted to do so, do not squish the tick! Ticks carrying diseases may transmit the disease through your skin upon coming in contact with the tick's bodily fluids. Proper disposal of a tick entails placing the tick in a jar with alcohol. Contact your local state Board of Health. They will gladly identify the tick for you and provide you with valuable information.
1. Contact a local university extension office for speakers and specimens commonly found in your area.
The local County Health Department also may be able to provide speakers on diseases of ticks, prevention, and proper removal.
2. Invite a local entomologist to speak in your classroom.
Ask him/her to bring specimens and pictures of ticks.
Preparing for Speakers
What do you and your students want to know? Have a list of questions for your speaker. If possible, call ahead of time and provide the speaker with the questions. After the speaker leaves, have the class summarize the information and write journal entries of the information that was most interesting and/or beneficial. Journal entries should also include drawings of ticks. Write and/or orally share "tick stories" if you or someone you know has had any encounters with ticks. Include a discussion of how to avoid ticks.
- TICKS and What You Can Do About Them, Roger Drummond, 1990. Wilderness Press, Berkeley, California.
- Microsoft Encarta software. Ticks.
- Emedicine Health Ticks - http://www.emedicinehealth.com/ticks/article_em.htm
- Iowa State University, Entomology Image Gallery- http://www.ent.iastate.edu/
- Tick Biology, University of California -http://entomology.ucdavis.edu/faculty/rbkimsey/tickbio.html
Initial development and printing of this fact sheet was funded by an Eisenhower Grant to the Partnership for Arid Lands Stewardship. Written by: Mary Moore; Series Editor: Georganne O'Connor; Design: WinSome Design; Printing: Eagle Printing and Graphic Design; First Printing: December 1997; Web Development: WinSome Design.