Data on the degree and duration of deltamethrin flea control on prairie dog colonies, with 3 prairie dog species at 6 sites across 3 US states. Fleas were combed (COMB) from live-trapped prairie dogs or swabbed (SWAB) from prairie dog burrows on non-treated (Non) sites and nearby sites treated with deltamethrin dust for flea control (Dusted). Each line of data is from an individual prairie dog or burrow. The first set of data, Shortterm BACI, includes data from before-after-control-impact (BACI) experiments comparing the abundance of fleas on prairie dogs at paired non-treated and treated sites in 2 time intervals: before treatments (Before) and 2 to 65 days after treatments (After). The second set of data, Moderate 1 year, includes data on the abundance of fleas on prairie dogs at paired non-treated and treated sites 7 to 13 months after treated sites had been treated with deltamethrin dust. The third set of data, Longterm 2 year, includes data on the abundance of fleas on prairie dogs (COMB) and in burrows (SWAB) at paired non-treated and treated sites 21 to 24 months after treated sites had been treated with deltamethrin. The fourth set of data, Dust days and grams, includes data on the abundance of fleas on prairie dogs at treated sites 7 to 13 months after deltamethrin treatments, and is restricted to sites with known amounts of dust (average grams) infused into prairie dog burrows. Funding and logistical support were provided by U. S. Fish and Wildlife Service; U. S. Geological Survey; U. S. Forest Service; Bureau of Land Management; Denver Zoological Foundation; Utah Division of Wildlife Resources and the Utah Department of Natural Resources Endangered Species Mitigation Fund; Bryce Canyon National Park; Badlands National Park; Dixie National Forest; Bureau of Land Management offices in Utah (Vernal, Cedar City, Richfield, and Torrey), Colorado (Meeker), and Montana (Malta); Colorado State University; Prairie Wildlife Research; National Fish and Wildlife Foundation; World Wildlife Fund; and Centers for Disease Control and Prevention.