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CODY URBAN DEER CLASSIFICATION/TREND SURVEY – 2021 Summary of 2021 Efforts On 12/16/2021, 13 WGFD and 1 City of Cody Police Department personnel conducted a classification/trend survey of deer within the city limits of Cody. The city was broken out into 10 Count Blocks (Figure and all deer encountered were classified into sex/age categories (adult buck, yearling buck, doe, fawn). Surveys were initiated at approximately 2:30 pm and continued until dark, approximately 5:00 pm. Figure 1. Cody urban deer survey count blocks. ---PAGE BREAK--- Results of 2021 Survey Date: 12/16/2021 Observers: J Burckhardt, Class, Mong, Skorupski, D. Smith, Hochhalter, Roy, Winter, Gerharter, Olson, Quick, Gambus, Crane, Heydenberk (Cody PD). Total Deer Observations (includes white-tailed deer) Table 1. 2021 observation data for all count blocks. Location Ad Bucks Yrl Bucks Does Fawns Unknown Total CB1 0 0 0 0 2 2 CB2 0 0 2 1 0 3 CB3 0 2 2 2 0 6 CB4 1 1 13 9 0 24 CB5 1 0 6 6 0 21 CB6 1 1 6 3 0 17 CB7 2 0 12 10 0 15 CB8 0 0 1 1 0 2 CB9 2 2 6 7 0 17 CB10 2 7 30 23 0 62 TOTAL 9 13 78 62 2 164 29 bucks:100 does, 79 fawns:100 does A total of 164 deer were observed within the City Limits of Cody. Deer fawn:doe ratios were 79:100 in the City Limits. Total buck ratios were 29:100 in the city limits with yearling buck ratios of 17:100 in the city limits and 12:100 for adult bucks. Summary of Historical Data The total number of deer observed in the city limits from 2011 to 2021 overall has been showing a decreasing trend (Table 2, Figure The 2021 count was lower than the 2020 count by 2 deer and below the five-year average of 208. Within each count block, there was a decrease in total deer counted in 5 count blocks compared to increases in 5 count blocks(Figure There has been a continual decrease in total number of deer counted in the city limits since 2015. There was a major decrease in the buck ratio from 2020 by 13:100, the 2020 ratio of 29:100 is more aligned with the wild populations but the extreme decrease from 2020 to 2021 may indicate impacts from Chronic Wasting Disease (CWD). There has been a significant increase in the overall increase in the CWD rate among deer tested in the City limits (Figure ---PAGE BREAK--- Deer Counts Table 2. Historical total count data (including white-tailed deer) within each Cody count block from 2011 to 2021. Figure 2. Total numbers of deer (including white-tailed deer) counted in all Cody city count blocks from 2011 to 2021. Count Block 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 1 35 42 59 57 60 19 28 24 12 7 2 2 0 0 0 24 9 0 9 0 0 0 3 3 68 41 49 0 26 32 14 14 26 22 6 4 25 16 12 11 15 5 8 9 3 14 24 5 56 46 43 32 43 29 37 31 6 21 13 6 10 18 9 22 33 25 8 13 19 17 11 7 42 25 27 0 0 49 29 24 6 15 24 8 1 8 18 31 34 17 22 13 24 24 2 9 20 33 26 7 22 31 30 20 27 8 17 10 50 30 49 84 41 51 57 44 57 38 62 Total 307 259 292 268 283 258 242 192 180 166 164 ---PAGE BREAK--- Figure 3. Count block comparison data from 2020 to 2021. This figure shows change in deer numbers within each count block from 2020 to 2021. Shown above each set of bars is the change between years (black = increase, red = decrease in numbers). -22 +3 -16 -6 +10 -8 -5 +24 +9 +9 ---PAGE BREAK--- Table 3. Cody town deer estimated influence of different adult doe removal scenarios 25 and 50) on the population. There are many assumptions made in this model that could have influences on the total number estimated for 2022. The estimates do not account for any movement of deer into or out of the town population. The estimates also use the 2021 count data, which should be considered a minimum count because it is impossible to have 100% accuracy with a wildlife survey. Annual survival of deer (both adults and fawns) used in the estimates from one year to the next has been adjusted based on higher CWD rates over the last few years and is lower than what we would see in the wild on a “normal” weather year. The number of potential fawns added to the population in 2022 is based on the 2021 fawn ratio of 79:100 adult does. Overall, this is a very conservative estimate with many unaccounted for variables and will most likely predict a lower number of deer than what will actually be observed in town. Based on estimates from 2020, we could be as many as 40 deer off from our estimates. Zero Adult Doe Removals Removal # 0 2021 Count Data Does Fawns (bucks and does) Bucks Total Adult Deer Fawn Deer 78 62 22 164 78% 60% # of deer surviving into summer of 2022 61 37 17 # of potential fawns (doe and bucks) that will add to total numbers in 2022 48 2022 Estimated Total 163 Annual Survival Rate ---PAGE BREAK--- Figure 4. Percent of Chronic Wasting Disease positive deer tested within the Cody City Limits 2018-2021. The total number of deer sampled is listed within the bars. *Low sample size for 2021. 16 48 43 49 *