Data on mouse capture histories during before-after and before-after-control-impact experimental evaluations of fipronil bait pellet “FipBit” safety, South Dakota, USA, 2022 and 2023

We evaluated the safety of fipronil bait pellets (FipBits) with two cricetids that commonly occupy colonies of black-tailed prairie dogs (Cynomys spp.; BTPDs): western deer mice (Peromyscus sonoriensis) and northern grasshopper mice (Onychomys leucogaster). We studied mice within three adjacent, interrelated management areas: Buffalo Gap National Grassland, including Conata Basin, and Badlands National Park, South Dakota, USA. The Buffalo Gap is administered by the U.S. Department of Agriculture Forest Service. Badlands is administered by the National Park Service.This release includes data from two field experiments. The first experiment (July-August 2022) involved a before-after design with sampling on treatment sites in the central portion of a BTPD colony before and after treatments. The second field experiment (July-August 2023) involved “BACI” before-after-control-impact study design with sampling before and after treatments on replicate treatment (impact) and nontreated (control) sites paired ecologically by similar physiographic and biotic features within BTPD colonies.We studied mice on 0.81-ha trapping grids (Krebs et al., 2011) centered on the study plots described below, with 100 traps/gird at 10 m spacing between neighboring Sherman traps (123 traps/ha; HB Sherman Inc., Tallahassee, FL, USA; 7.62 × 7.62 × 25.4 cm non-folding and 8 × 9 × 23 cm folding).In 2022, we conducted a before-after experiment on a portion of a BTPD colony named Conata West, estimated in 2021 as 395 ha of BTPD-occupied habitat in the Conata Basin. This experiment included three treatment sites, each 1.44 ha in size and separated from the nearest neighbor, edge-to-edge, by ~260-380 m. FipBits (0.89-1.13 mg fipronil/bait, distributed evenly among the plots) were applied by site management personnel in early August to all three 1.44 ha plots (and 50 m buffers) at 75 baits/ha. Trapping was completed on all three plots, on consecutive nights, for 6 nights just before treatments and 5 nights from 6-10 d after treatments.In 2023, we conducted a replicated BACI experiment on separate BTPD colonies, Pinnacles and Prairie Wind South in Badlands National Park, estimated in 2022 to be 63 and 27 ha. Each colony included two treatment sites and one nontreated site; each plot was separated by ≥150 m on Pinnacles and ≥75 m on Prairie Wind South. In this case, plot sizes varied (depending on BTPD dispersions/densities) from 0.85 to 2.06 ha (the primary objective was to evaluate flea control on BTPDs). At each colony, we evaluated two FipBit concentrations on separate treatment plots (0.40 and 1.3 mg fipronil/bait), with applications completed in late July by site management personnel at 125 baits/ha (and 20 m plot buffers). Trapping was completed on nearly consecutive nights for 3 nights just before treatments and 3 nights 11-15 d after treatments.Each trap night, Sherman traps were set in the late evening and checked in the early morning. We processed mice at trap locations or predetermined stations adjacent to the trapping grids. For identification purposes, we marked each small mammal with a numbered metal tag in each ear (National Band and Tag Co., Newport, KY, USA, Model 1005-1). We released all individuals at their point of capture.This release includes one combined dataset, Mice_FipBits_Capture_Histories_2022_2023, with separate sheets for the 2022 and 2023 experiments. Each line of data on each sheet represents an individual mouse (Mouse). The column for treatment (Treatment) on the sheet for the 2022 experiment includes “FipBit” pellets with 0.89-1.13 mg fipronil/bait. The column for treatment (Treatment) on the sheet for the 2023 experiment includes “LowFipBit” pellets with (0.40 mg fipronil/bait) and “HighFipBit” pellets (1.3 mg fipronil/bait).Mouse capture histories on each sheet (CaptureHistory) summarize whether a particular mouse was captured during each night of sampling in each experiment (6 nights before and 5 nights after treatments in 2022 = 11 potential capture nights, 3 nights before and 3 nights after in 2023 = 6 potential capture nights). If a mouse was captured on a particular night, the corresponding capture history value for that night = 1 for that mouse (captured). If a mouse was not captured on a particular night, the corresponding capture history value for that night = 0 for that mouse (not captured).Field work was conducted under U.S. Geological Survey Institutional Animal Use and Care (IACUC) protocol 2018-04 (Fort Collins Science Center). All protocols followed guidelines of the American Society of Mammalogists (Sikes and Animal Care and Use Committee of the American Society of Mammalogists, 2016).Sikes, R.S. and Animal Care and Use Committee of the American Society of Mammalogists, 2016. 2016 Guidelines of the American Society of Mammalogists for the use of wild mammals in research and education. Journal of Mammalogy, 97(3), pp.663-688.