The Winter Tick

The Winter Tick (Dermacentor albipictus)

This tick, one of many, just turned up on a young horse that was recently brought into the Williams Lake Stampede Grounds.  It is a pretty common tick in the Cariboo-Chilcotin, but not so much in the immediate Williams Lake area.

The winter tick is what we call a one-host tick because it completes its life cycle on a single animal, usually large mammals like horses, cattle or moose.  These animals pick up the tick in the fall, often in very large numbers.  Initially even a good horse groomer will not notice them as they are tiny, but as fall progresses into winter they will grow and then one day, a horse owner will feel hundreds or thousands of distinct bumps under the hair.  It may be suspected that the horse recently became a host for the ticks but, in fact, the ticks had been there for a few months.

Heavy loads cause severe itching for the host.  The host will try to rub off the tick by pushing up against trees or other solid objects.  Unfortunately, they rub so hard and frequently that they lose a great deal of hair which can impact their health during the winter.  The heavy hair loss gives rise to what are called 'Ghost Moose.'  Combine this condition with a late winter cold snap and significant mortality can occur.  Fortunately, this tick is not considered a serious risk for transmitting diseases.  

In the spring the ticks will naturally fall to the ground to lay eggs.  The eggs will hatch in about 6 weeks and then spend the summer dormant (sleeping) in the low vegetation.  In the fall they climb grasses or shrubs, in great numbers, and are picked up by the next host.

So, back to the young horse at the Stampede Grounds.  What to do? Simple.  Don't transport him around because this might spread the ticks at a time in the life cycle when eggs will be laid.  Just treat for the ticks as soon as possible and try to collect any that fall.

For more information about ticks in the Cariboo-Chilcotin, click here.

Photo credit: Me