The fox squirrel (Sciurus niger L.) is a rodent of medium size expressing no sexual dimorphism. Because of its broad and diverse habitat, the fox squirrel is a likely means of transfer and a perpetuator of potential arthropod-borne disease vectors. It is thus useful to gain knowledge of what types of ectoparasites occur on the fox squirrel throughout the year. Additionally, the ability to control ectoparasites on fox squirrels could prevent the transfer of disease vectors.
The first part of this study was a survey of ectoparasites on fox squirrels, which were live-trapped or harvested with a firearm. Squirrels that were live-trapped were sedated with 0.2cc of Rompun® (Xylazine) through intramuscular injection and were closely examined for ectoparasites. Sacrificed squirrels were examined as quickly as possible.
Ectoparasites collected from fox squirrels included all lifestages of Dermacentor variabilis (Say), larval and nymphal Amblyomma americanum (L.), nymphal Ixodes scapularis Say, adult Orchopeus howardii (Baker) and Nosopsyllus fasciatus (Bosc), immature and adult Neohaematopinus sciurinus Mjöberg and Hoplopleura sciuricola Ferris.
The second part of this study focused on tick control. Eight squirrels were removed from our laboratory colony, sedated, fitted with nylon sleeves and infested with 50 nymphal D. variabilis. The squirrels were placed into individual cages and held over water. On day three, four of the squirrels were treated with 3mL of medication diluted in refined oil and four with simply 3mL of refined oil. Ticks were continually collected from the water and weighed through day ten. The infestations were repeated 30 days after treatment.
In both trials, ticks feeding on untreated squirrels attached readily and fed to engorgement. Ticks feeding on treated animals detached at the time of treatment or became replete without engorgement. Percent engorgement and tick weight after feeding were significantly greater for ticks feeding on untreated animals than those feeding on untreated animals.
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA