Epizootic outbreaks of sylvatic
plague have dramatically influenced prairie dog (Cynomys sp.) populations across North America. While a great deal of debate surrounds the cause and persistence of
plague, flea control can stop the spread of
plague epizootic outbreaks and even increase prairie dog survival under non-epizootic conditions. We investigated a newly-developed
imidacloprid-treated grain bait that could potentially reduce
flea infestations and mitigate the effects of
plague on black-tailed prairie dogs (C. ludovicianus). We used a study design involving randomly assigned experimental and control study plots to assess the effectiveness of the systemic flea control product. We observed a significant difference in flea prevalence and abundance between experimental and control sites on three of the four sites treated with a single application of
imidacloprid-treated grain bait for up to 90 days post-treatment. We observed an even greater reduction in
flea infestations following the double application of treatment bait on two of three additional experimental sites. While we were unable to reduce
flea infestations to the extent reported for more commonly used topical
insecticides containing
deltamethrin,
imidacloprid might still be effective at reducing the risk of
plague and halting epizootics. In addition, this systemic product can be more rapidly applied than topical
insecticides, providing managers with a tool to quickly reduce
flea infestations. Future research is needed to evaluate the effectiveness of different application timing and rates, the utility of the product in limiting
plague, and the potential effects on non-target species that might also consume the treated bait.