Relative utilization of reptiles and rodents as hosts by immature Ixodes scapularis (Acari: Ixodidae) in the coastal plain of North Carolina, USA.

Abstract

The interaction of immature black-legged ticks, Ixodes scapularis, with reptiles and rodents was investigated in various woodland habitats in the coastal plain of North Carolina. Reptiles were sampled from April 1 to September 30, 1991. No ticks were found on 95 specimens representing 16 species of snakes. Ticks were found on 54 (36.7%) of 147 lizards. I. scapularis was the only tick recovered from lizards. Some lizards were collected in drift fence traps each month of the study except August. Capture rates averaged one lizard per 16 trap-days. Larvae and nymphs of I. scapularis were removed from the southeastern five-lined skink (Eumeces inexpectatus), the ground skink (Scincella lateralis), the broad-headed skink (E. laticeps) and the eastern glass lizard (Ophisaurus ventralis), but ticks were not found on three other lizard species. Tick infestation rates and loads for parasitized species are presented. Ticks were almost exclusively attached at the base or in the axils of forelimbs of skinks and in the lateral grooves of eastern glass lizards. Rodents were live-trapped at sites where lizards were sampled and at other sites from 1 July, 1990 to 30 January, 1992. Capture rates averaged one rodent per 47 trap-nights. Ticks were found on 23 (17.8%) of 129 animals inspected. Five species of rodents were examined but only four species were found to be tick-infested. In contrast to lizards, few I. scapularis were collected. Rodents, principally the white-footed mouse (Peromyscus leucopus) and cotton mouse (P. gossypinus) were most frequently infested with immature American dog ticks, Dermacentor variabilis, during winter and early spring months. Burdens of D. variabilis on these rodents averaged 0.3 ticks per rodent. Effects of the diversion of ticks from feeding on Peromyscus mice on the transmission of the Lyme disease spirochete are discussed.