Ticks, of which there are more than 500 species worldwide, are parasitic arthropods closely related to mites. They are not insects. Most ticks feed on the blood of warm-blooded mammals, but some species also feed on birds, reptiles, and even amphibians. Fish are apparently the only vertebrates not plagued by these tiny bloodsuckers. Many species of ticks can transmit diseases from an infected host to other, uninfected hosts. Some of the more frequently transmitted organisms include parasitic worms, viruses, bacteria, spirochetes, and rickettsia’s. The most common of these to Pennsylvania are spirochetes, which cause Lyme disease, and rickettsia’s, which cause Rocky Mountain spotted fever. Currently, more than 25 species of ticks have been identified in Pennsylvania. Of these, 4 species account for nearly all tick problems in Pennsylvania.

(1) The American dog tick

(2) The black- legged tick

(3) The groundhog tick

(4) The lone star tick

The groundhog tick is found east of the Rockies, from Texas to South Dakota, and northeastward, through Maine. This tick is less common, or at least less commonly encountered, than the other ticks. It is however, a relatively common tick in portions of western and northern Pennsylvania.

This tick is very host specific for groundhogs, but occasionally it is found on birds, small animals, or humans.

It is not considered to be an important vector of Lyme disease since it tends to feed only on groundhogs. In laboratory studies, larval groundhog ticks would not feed on white-footed mice (Peromyscus species) and as such is probably not a good candidate as a vector for Lyme disease. Additionally, it is not a known vector for any other diseases.