Know your ticks: Ixodes angustus (no common name)

Ixodes angustus ticks are probably better known in British Columbia than elsewhere in Canada due to the role this species is thought to play in the transmission of Lyme disease in Canada's westernmost province.

These tiny, tan coloured ticks are generalist feeders that have been known to dine on the blood of more than 90 different host species, most notably chipmunks, mice, rats, shrews, squirrels and voles. Very rarely do they bite humans. However, Ixodes angustus ticks can carry Lyme bacteria and transmit it to their hosts, so they're thought to play a minor role in the transmission of Lyme disease in this country.

Unlike blacklegged ticks (Ixodes scapularis) or western blacklegged ticks (Ixodes pacificus) which actively seek hosts within their local environment, Ixodes angustus ticks tend to be content to remain sequestered in the nests of the creatures they feed on and therefore rarely come into contact with humans. This difference in habits makes it far more likely that someone in Canada will pick up a Lyme infection from blacklegged ticks (central/Eastern Canada) or western blacklegged ticks (British Columbia) than from Ixodes angustus ticks.

This tick isn’t terribly well researched and little is known about its habits other than it likes to hang out in cool, damp places near rivers or in coniferous forests.

Diseases carried: Lyme disease. There is some evidence that this species may also carry anaplasma, babesia and/or Powassan virus.

Where found: Mostly encountered in BC, but widespread in low numbers throughout most of Canada with the exception of Saskatchewan.

Photo courtesy of Digital Commons@Georgia Southern.