Quantifying temporal variation in dietary niche to reveal drivers of past population declines Amanda E. Cheeseman1,2, Brian P. Tanis1,3, Elmer J. Finck1 1Department of Biological Sciences, Fort Hays State University, Hays, KS, 67601 (AEC, BPT, EJF) 2Department of Environmental and Forest Biology, SUNY College of Environmental Science and Forestry, Syracuse, NY 13210 (AEC, Current affiliation) 3Department of Integrative Biology, Oregon State University, Corvallis, OR 97331 (BPT, Current affiliation) Corresponding Author: Amanda E. Cheeseman acheesem@esf.edu Cheeseman_2021_skunk_isotops.csv d13C and d15N isotope values for Spotted skunk (Spilogale putorius) and striped skunk (Mephitis mephitis) collections from Kansas 1894-2012 with associated landscape and weather data. CensusYr- Year of associated census data County-County of specimen collection d13C-Raw d13C values d15N-Raw d15N values Genera-Genera indicating which species Mephitis mephitis or Spilogale putorius CatalogNum.x-Museum code and catalog number of specimen OR unique code given to road collected specimens State-State of specimen collection Latitude- Latitude of specimen collection Longitude-Longitude of specimen collection Year-Year of specimen collection d13C.ADJ-Suess effect corrected d13C values P.Corn-Proportion of land in corn at county level, calculated as land in corn/county land area; data obtained from US Census of Agriculture data Total.Land.area.in.Acres- Total land area in acres for the county; data obtained from US Census of Agriculture data Total.land.in.farms..acres.-Total land are in farms (acres) for the county; data obtained from US Census of Agriculture data Average.size.of.farm.in.acres-Average farm size (acres) for the county; data obtained from US Census of Agriculture data Land.Ag-Total land area in agriculture (acres);data obtained from US Census of Agriculture data DietYear-Year of hair growth Precip-Average precipitation at nearest weather station during period of hair growth; August - October; calculated using RNOAA Temp-Average temperature at nearest weather station during period of hair growth; August - October; calculated using RNOAA Station- Weather station used for Precip and Temp averages P.Ag-Proportion of the land area in agriculture at the county level, calculated as agricultural land/county land area;data obtained from US Census of Agriculture data Cheeseman_2021_skunk_harvest.csv Harvest data used to assess population trends through time for Spilogale putorius and Mephitis mephitis Harvest data compiled from Kansas Fish and Game Commission and the United States Fish and the Wildlife Service Wildlife Leaflets Series Year-Harvest year SppuHarv-The number of Spilogale putorius harvested in Kansas SppuSold-The number of Spilogale putorius sold in Kansas MemeHarv-The number of Mephitis mephitis harvested in Kansas MemeSold-The number of Mephitis mephitis sold in Kansas MemeAll-Grouped harvested or sold Mephitis mephitis in the state of Kansas depending on recording method in that year TotalFurLicenseSold-The number of adult fur licenses sold in the state of Kansas ADULTFurLicSold-The total number of fur licenses sold in the state of Kansas SeasonStart-The date of the start of the trapping season SeasonEnd-The date of the end of the trapping season SeasonDays-The length of the trapping season TrapEffort-Trapping effort calculated as season length x fur licenses sold MemeFurPricesKS-Average pelt price for Mephitis mephitis in Kansas SppuFurPricesKS-Average pelt price for Spilogale putorius in Kansas KS.Meme.Adj-Average pelt price for Spilogale putoris in Kansas corrected for inflation KS.Sppu.Adj-Average pelt price for Spilogale putoris in Kansas corrected for inflation MO.Meme-Average pelt price for Mephitis mephitis in Missouri MO.meme.Adj-Average pelt price for Mephitis mephitis in Missouri corrected for inflation MO.Sppu-Average pelt price for Spilogale putoris in Missouri MO.SppuAdj-Average pelt price for Spilogale putoris in Missouri corrected for inflation Cheeseman_2021_KS_Ag_Census.csv Land use measures (corn, Land in agiculutre, and average farm size) from 1890 - 2007 at the county level Data obtained from the US Census of Agriculture year-Census year county-County of data Corn grown from all purposes2-Area planted in corn (Zea maize, acres) per county Total Land area in Acres- Total land area of county Average size of farm in acres- Per county average farm size (acres) Land.Ag- Land in cropped agriculture (acres) per county