(Formerly called the Deer Tick.)

Order:    Acari

Family:    Ixodidae

Latin Name:   Ixodes scapularis Ratz. ( formerly I. dammini )

Common Names:   Deer tick, Blacklegged Tick

Introduction
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Widespread in the Eastern US. In Canada, it has been collected in Ontario, Quebec, and all Atlantic provinces.

Nymphs and adults: 3 - 7 mm; dark brown to black in colour with no white marking on dorsal surface; engorged females appear to have an orange/yellow coloured abdomen; adults and nymphs have 8 legs.

Life History
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The blacklegged tick is a three host tick and takes two years to complete its life cycle. The blacklegged tick is a different species from the dog or wood tick, one of the most common ticks found in Nova Scotia.
(view a comparison sketch of the blacklegged and dog (wood) tick)

In early spring, the eggs are laid by an engorged female in the vegetation on the forest floor. Tiny six-legged larvae emerge in early summer with larval activity at its highest in August. The larvae feed on a variety of hosts, including birds and small mammals. In the fall, the larval ticks drop off their hosts and overwinter as engorged larvae.

The following spring the larvae molt into the larger nymph stage. Throughout the summer the nymphs feed on birds and larger mammals, such as deer, dogs, and humans. This is the stage at which they are most likely to be transported to new regions via migrating birds and animals.

In the fall, the engorged nymph drops off its host to the forest floor where it transforms into the adult stage. Adults remain active throughout the fall into the mild days of winter, feeding primarily on deer and larger mammals, including humans. Engorged ticks overwinter in the forest floor litter.

Problem Rating
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In the summer of 2002, Nova Scotia recorded it’s first known, endemic, human case of Lyme Disease. First recognized in 1975 in Lyme, Connecticut, the disease has since been detected in most of North America, Asia and Europe. In Nova Scotia, the blacklegged tick is the primary vector of Borrelia burgdorferi, the agent that causes Lyme Disease.

Since the discovery of a Lyme-positive blacklegged tick from Antigonish County in July, 2002, individual I. scapularis have been collected throughout Nova Scotia. It has since been determined that this species is now established in and around three locations in the province: Bedford, Lunenburg, and Gunning Cove. Continued study is needed to determine the status of this species in Nova Scotia and the public risk of encountering Lyme disease. Special precautions should be now considered when traveling in our woodlands to avoid contracting this disease.

Control Options
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For more complete information on health issues relating to the blacklegged tick, please visit the NS Department of Health website.

Some tips to prevent tick encounters include:

1. Avoid tall grasses and shrubby areas, favourite habitats of ticks. Keep lawns mowed regularly.
2. Personal protection includes wearing long pants tucked into socks, long sleeve shirts and hats, and repellants containing DEET can be sprayed on outer clothing.
3. Careful examination of your person and pets following exposure to potential tick habitats. Use a wide flea comb on your pets following an outing to remove any ticks not yet attached.
4. Discourage deer and other wild animals from your yard and home.

How to remove a tick:

Since it takes a tick a few hours to become fully attached, pay close attention to Tip 3 (above). The best way to remove them is to get rid of them before they have a chance to “latch on”.

If a tick becomes attached, use tweezers to carefully grasp the body of the tick as close to the skin as possible. Pull slowly to allow the tick to release it’s mouthparts prohibiting breakage within the skin. Avoid twisting or turning the tick because this could also cause the mouth parts to be broken off. If the head or any part of the mouth parts are lost, species identification becomes more difficult and the risk of the bite becoming infected increases.

DO NOT use matches, cigarettes, pins, or gasoline to attempt to remove the tick. This may only irritate the tick into spitting up contents of it’s stomach into the host. The use of Vaseline or other oil products is not recommended, because it may take hours to suffocate a tiny oil coated tick.

Following the removal of the tick wash the area thoroughly and apply an antiseptic, such as alcohol. If infection occurs, contact your doctor.

The NS Department of Natural Resources, in conjunction with the NS Department of Health, is currently undertaking a province-wide tick survey. We are very interested in all ticks collected in Nova Scotia off pets and people.

Procedure for handling ticks after removal:

Once ticks are removed, place in a water tight container and preserve with 70% alcohol. Label containers with a permanent marker. Documentation of local, date collected, host and collector greatly aids to a proper identification. Also indicate whether the host has been traveling and if so, where. Wash hands and tweezers thoroughly with warm soapy water after handling the ticks.

All tick specimens can be forwarded to any NS Department of Natural Resources office or the Museum of Natural History in Halifax for identification.