Deer Tick



Ixodes scapularis has been reported from at least 125 different species of hosts. The adults appear to prefer medium to larger sized mammals and are only moderately host-specific, as they have been recorded from at least 27 different mammalian and one lizard host species.

The white-tailed deer (Odocoileus virginianus) is the most commonly infested mammalian species. Populations of I. scapularis appear most abundant in areas where deer are also numerous (Sonenshine, 1991).

Figure 1: Deer host of Ixodes scapularis

However, adult deer ticks have also been recorded from black bears (Ursus americanus) in Wisconsin; opossums (Didelphis virginiana), raccoons (Procyon lotor), and skunks (Mephitis mephitis) in New York and woodchucks (Marmota monax), grey squirrels (Sciurus carolinensis) and red fox (Vulpes vulpes) (Sonenshine, 1991).

Immature I. scapularis are less host-specific. They have been reported from at least 41 mammalian, 57 avian species and 14 species of lizards. In some instances the immatures can be found on the same hosts as the adults; for example, both larvae and nymphs can be found on white-tailed deer. However, in most instances the immatures prefer smaller mammalian hosts, as well as ground-nesting and ground-foraging birds.

The white-footed mouse, Peromyscus leucopus, is an important host for larval I. scapularis (Sonenshine, 1991).

Figure 2: White-footed mouse as host for larval Ixodes scapularis

Other hosts, such as chipmunks (Tamais striatus) and meadow voles (Microtus pennsylvanicus) may serve as hosts to larval I. scapularis .

Short-tailed shrews (Blarina brevicauda), southern red-backed voles (Clethrionomys gapperi), pine voles (Microtus pinetorum), eastern cottontail rabbits (Sylvilagus floridanus) and meadow jumping mice (Zapus hudsonicus) also harbor immature I. scapularis.


Further information

  • Sonenshine DE: Biology of Ticks. Part 1, 1991, Oxford University Press, New York

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