Ticks are present across Montana’s diverse landscapes, found in various outdoor environments. These small arachnids pose a potential health concern for residents and visitors engaging in activities like hiking, camping, or gardening. Understanding the types of ticks common in Montana, the diseases they can transmit, and how to protect oneself is important for safely enjoying the state’s natural beauty.
Common Ticks and Their Habitats in Montana
Montana is home to several tick species, with the Rocky Mountain Wood Tick (Dermacentor andersoni) and the American Dog Tick (Dermacentor variabilis) being the most frequently encountered. The Rocky Mountain Wood Tick measures approximately 1/8 to 1/4 inch long when unfed. These ticks are widespread across Montana, preferring habitats such as tall grasses, low brush, stream corridors, and south-facing sagebrush slopes, though they can also be found in urban green spaces. Their activity typically peaks from spring through early summer, usually April to July, diminishing during hot, dry mid-summer conditions.
The American Dog Tick, while similar in appearance to the Rocky Mountain Wood Tick, is generally found in eastern Montana. Females are reddish-brown with a creamy-white dorsal shield, while males have cream or gray markings over their reddish-brown bodies. These ticks thrive in wooded areas, abandoned fields with medium-height grasses, shrubs, and open areas between wetlands and forests. American Dog Ticks are active from mid-April to early September, with peak activity in May and June.
Tick-Borne Diseases in Montana
Ticks in Montana can transmit several diseases. Rocky Mountain Spotted Fever (RMSF) is a bacterial infection primarily transmitted by the Rocky Mountain Wood Tick and American Dog Tick. Symptoms typically appear 3 to 12 days after a bite and can include sudden fever, headache, and a rash. Transmission requires the tick to be attached for at least 10 hours.
Colorado Tick Fever (CTF) is a viral illness transmitted by the Rocky Mountain Wood Tick. Symptoms include fever that may recur in cycles, body aches, chills, and fatigue. Tularemia, often called “rabbit fever,” is a bacterial disease spread by Rocky Mountain Wood Ticks and American Dog Ticks, as well as through contact with infected animals. Symptoms vary but commonly include sudden fever, headaches, chills, and potentially skin ulcers or swollen lymph nodes.
Lyme disease, caused by the bacterium Borrelia burgdorferi, has historically had no Montana-acquired cases. However, the blacklegged tick (Ixodes scapularis), a primary vector for Lyme disease, has recently been identified in eastern Montana, specifically Dawson and Sheridan counties. While these specific ticks tested negative for Lyme disease pathogens, their presence indicates a potential for increased exposure to illnesses not previously widespread in Montana.
Prevention and Safe Removal
When engaging in outdoor activities, wearing appropriate clothing can significantly reduce exposure; this includes long-sleeved shirts, long pants tucked into socks, and hats. Choosing light-colored clothing makes it easier to spot ticks before they attach. Avoiding dense vegetation, such as tall grasses and brush, and staying in the center of trails also helps minimize contact.
Using EPA-registered insect repellents containing active ingredients like DEET or picaridin on exposed skin and clothing provides effective protection against ticks. Permethrin-treated clothing and gear offer additional defense, as permethrin can remain protective through several washings. After spending time outdoors, performing thorough tick checks on yourself, children, and pets is important. Pay close attention to areas like the underarms, behind the knees, around the waist, and in hair. Showering within a few hours of coming indoors can wash off unattached ticks and provides another opportunity for a thorough check. Placing dry clothes in a dryer on high heat for 10 minutes can also kill any lingering ticks.
If a tick is found attached, prompt and correct removal is important to reduce the risk of disease transmission. Use clean, fine-tipped tweezers to grasp the tick as close to the skin’s surface as possible. Pull upward with steady, even pressure, avoiding twisting or jerking the tick, which can cause its mouthparts to break off and remain in the skin. After removal, clean the bite area and your hands thoroughly with rubbing alcohol or soap and water. Dispose of the tick by placing it in a sealed container, wrapping it tightly in tape, flushing it down the toilet, or putting it in alcohol.