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CODY URBAN DEER CLASSIFICATION/TREND SURVEY – 2020 Summary of 2020 Efforts On 12/17/2020, 9 WGFD personnel conducted a classification/trend survey of deer within the city limits of Cody. Due to Covid restrictions only one person per vehicle were allowed to conduct the count. 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 2:00 pm and continued until dark, approximately 5:00 pm. Figure 1. Cody urban deer survey count blocks. ---PAGE BREAK--- Results of 2020 Survey Date: 12/17/2020 Observers: J Burckhardt, Class, Gerrity, Lassetter, Mong, Skorupski, D. Smith, Swanson, Hochhalter. Total Deer Observations (includes white-tailed deer) Table 1. 2020 observation data for all count blocks. Location Ad Bucks Yrl Bucks Does Fawns Unknown Total CB1 1 0 4 2 0 7 CB2 0 0 0 0 0 0 CB3 4 1 6 11 0 22 CB4 1 1 6 6 0 14 CB5 2 5 9 5 0 21 CB6 0 1 8 8 0 17 CB7 1 1 6 7 0 15 CB8 3 3 8 10 0 24 CB9 3 0 4 1 0 8 CB10 2 2 24 9 1 38 TOTAL 17 14 75 59 1 166 42 bucks:100 does, 79 fawns:100 does A total of 166 deer were observed within the City Limits of Cody. Deer fawn:doe ratios were 79:100 in the City Limits. Total buck ratios were 42:100 in the city limits with yearling buck ratios of 19:100 in the city limits and 23:100 for adult bucks. Summary of Historical Data The total number of deer observed in the city limits from 2011 to 2020 overall has been showing a decreasing trend (Table 2, Figure The 2020 count was lower than the 2019 count by 14 deer and below the nine-year average of 253. Within each count block, there was a decrease in total deer counted in 5 count blocks compared to increases in 3 count blocks and no change in 2 count block (Figure There has been a continual decrease in total number of deer counted in the city limits since 2015. There was an increase in the buck ratio from 2019 by 4:100, the 2020 ratio of 42:100 is still much higher than observed in wild populations and may increase the potential for Chronic Wasting Disease transmission. The 2020 fawn ratio is high than those found in wild populations and may contribute to population growth in 2021. Based on a simple population estimate model that assumes a closed town population, meaning no deer leave town or no new deer come into town, removing no deer out of the population would result in an estimated increase of ~30 deer. Table 3 shows different removal scenarios with estimated population results based on many assumptions. ---PAGE BREAK--- Deer Counts Table 2. Historical total count data (including white-tailed deer) within each Cody count block from 2011 to 2019. Count Block 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 1 35 42 59 57 60 19 28 24 12 7 2 0 0 0 24 9 0 9 0 0 0 3 68 41 49 0 26 32 14 14 26 22 4 25 16 12 11 15 5 8 9 3 14 5 56 46 43 32 43 29 37 31 6 21 6 10 18 9 22 33 25 8 13 19 17 7 42 25 27 0 0 49 29 24 6 15 8 1 8 18 31 34 17 22 13 24 24 9 20 33 26 7 22 31 30 20 27 8 10 50 30 49 84 41 51 57 44 57 38 Total 307 259 292 268 283 258 242 192 180 166 ---PAGE BREAK--- Figure 2. Total numbers of deer (including white-tailed deer) counted in all Cody city count blocks from 2011 to 2020. ---PAGE BREAK--- Figure 3. Count block comparison data from 2019 to 2020. This figure shows change in deer numbers within each count block from 2019 to 2020. Shown above each set of bars is the change between years (black = increase or no change in numbers, red = decrease in numbers). -19 0 -4 -2 +11 -19 -5 +15 +9 0 ---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 2021. The estimates do not account for any movement of deer into or out of the town population. The estimates also use the 2020 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 is lower than what we would see in the wild on a “normal” weather year. This lower survival estimate was used to account for the increased risks from car collisions and poor feed quality found in town. The number of potential fawns added to the population in 2021 is based on the 2020 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 2019, we could be as many as 40 deer off from our estimates. Zero Adult Doe Removals 25 Adult Doe Removals Removal # 0 2020 Count Data Does Fawns (bucks and does) Bucks Total Adult Deer Fawn Deer 75 59 31 166 90% 75% # of deer surviving into summer of 2020 68 44 28 # of potential fawns (doe and bucks) that will add to total numbers in 2021 53 2021 Estimated Total 193 Annual Survival Rate Removal # 25 2020 Count Data Does Fawns (bucks and does) Bucks Total Adult Deer Fawn Deer 75 59 31 166 90% 75% # of deer surviving into summer of 2020 43 44 28 # of potential fawns (doe and bucks) that will add to total numbers in 2021 34 2021 Estimated Total 148 Annual Survival Rate ---PAGE BREAK--- 50 Adult Doe Removals Removal # 50 2020 Count Data Does Fawns (bucks and does) Bucks Total Adult Deer Fawn Deer 75 59 31 166 90% 75% # of deer surviving into summer of 2020 18 44 28 # of potential fawns (doe and bucks) that will add to total numbers in 2021 14 2021 Estimated Total 103 Annual Survival Rate