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Hwy 97 Small Animal Fencing - PreInstallation Surveys PreliminaryProject: Reduced vehicle-animal collisions with installation of small animal exclusion fencing Contract: 133497 Deliverable 2: Preliminary report on pre-installation site monitoring, May to October, 2018 The first field season of the small animal road mortality study was conducted between May 9th and October 17th, 2018. The length of the field season was determined by a combination of animal activity and weather. A colder than average spring resulted in a start date later than originally anticipated (i.e., April). Likewise, a cool start to fall had very few animals (and no turtles) on the roads by mid-October. For the 15 sites, each was typically sampled on a weekly basis through the field season, resulting in 22 to 24 total visits per site. In a couple of instances, active road construction (i.e., resurfacing) prevented access to a site for a given week. In addition, during the first few weeks of the season (May) we were not able to sample every site weekly, resulting in a small number of gaps for this time period. Study sites were delineated with spray paint to ensure consistency in monitoring effort. Observers walked single file along each road segment, recording all mortality (and any live animals) on roads and within the first two feet of the shoulder. Taxa recorded included turtles, snakes, lizards, frogs, toads, birds, mammals, monarchs, and bumble bees. We encountered a total of 2,096 animals, including 372 turtles; the vast majority of these observations were deceased (Table 1). Four live turtles (all from Northeast Site 5) were observed crossing the road over the course of the field season. When safe to do so, live turtles were assisted across the highway in the direction they were headed. Sites varied greatly in frequency of turtle encounters, ranging from 0 to 73 total turtles (Figures 1a - o). Because sites varied in length from ~76 to ~625 m, we standardized for segment length to better facilitate comparisons among sites (see Table 1). We observed the highest rate of encounters at Northeast Site 5 (8.6 turtles / 100 feet) and the lowest rate at Southeast Site 3 where no turtles were found. The latter result, however, was likely heavily influenced by nearby road construction, where the southern end of the site was closed to traffic for the majority of the field season. The “construction effect” for this site will be better assessed after an additional 2 years of monitoring with the road open to traffic. We investigated seasonal movements of turtles as well (Table 2 and Figure 2). We documented an increase in turtle activity in late spring and again in the early fall. Presumably, the spike in May / June was related to movements to foraging areas from overwintering sites and / or females searching overland for appropriate nest sites. The peak in early fall was likely related to the movements of turtles back to overwintering sites. We also observed several snapping turtle hatchlings on roads in the early fall. Although seasonal trends in activity were generally consistent for both painted and snapping turtles, we note that there was less relative activity during mid-summer for snapping turtles. Additionally, sites for fence installation were finalized this summer and bids solicited from contractors. This process is being managed by MnDOT, and fence installation is scheduled to be completed by early spring 2019. Selection of sites for fencing was semi-randomized, based on the presence of target species, logistical feasibility of fence installation, anticipated costs, and broad geographic representation. There are currently five sites selected for treatment, five as corresponding controls, and five contingency sites, including two with little observed mortality and three that could be used for future mitigation efforts. Although high mortality sites are ultimately a priority for mitigation strategies, control and treatment sites were chosen randomly among sites (given the above financial and logistical constraints) where the presence of turtles was relatively consistent to facilitate robust statistical analyses. The selection process ensures that each treatment site has a corresponding and comparable control site along the same stretch of road. The locations of road mortalities from this season also helped to inform length and positioning of fences. In general, hotspots for turtle activity were found in locations where water comes closest to the road, identifying key target areas for future road underpass installations and improvements. Following fence installation during early spring, 2019, sites will be monitored on a weekly basis when temperatures warm enough to promote movement of turtles, the target species. We will deploy traffic counters in 2019 to quantify traffic volume as a potential predictor of road mortality. We will also install cameras to document turtle movements and supplement our weekly sampling, helping to determine if fencing is effective in redirecting turtles and other animals away from roads and / or to existing through-road infrastructure (i.e., bridges and culverts). Table 1. Summary Field Season 2018: Pre-fence installation site monitoring Sampling began on May 9th, 2018 and ended on October 17, 2018. During the field season each site was sampled 22 to 24 times. Monitoring occurred weekly, on average, to evaluate seasonal variability in activity patterns and mortality. A small number of live animals were sighted on roads during surveys. These included: 4 painted turtles, 5 leopard frogs, 7 toads, 6 snakes, 2 birds, 2 mammals, and 19 monarchs. All remaining individuals were deceased. Treatment (i.e. fencing) sites are indicated by bold/red text. Turtles Anurans Snakes Other Herpetofauna Birds Mammals Insects Site # Turtles/100 ft Region Site Painted turtles Snapping turtles Unknown Leopard frogs Green frogs American toads Other / Unknown All species All other species / Unknown All species Bats All other species Bumble bees Monarchs Totals Southeast 0 29 6 24 2 4 8 2 10 12 97 4.0 Southeast 1 11 4 1 1 5 1 1 5 29 4.3 Southeast 2 8 8 2 1 2 1 6 2 3 33 0.7 Southeast 3 5 1 1 1 1 9 0.0 Southeast 4 30 9 24 8 7 4 9 5 96 3.9 Northeast 5 64 8 1 14 1 5 6 5 1 13 1 2 8 5 134 8.6 Northeast 6 20 5 3 13 18 1 1 4 1 1 5 72 3.6 Northeast 7 3 3 1 3 4 5 1 20 0.8 Northeast 8 4 3 8 6 1 1 1 1 1 2 28 1.6 West 13 50 10 3 68 78 56 194 5 4 62 22 10 14 576 3.1 West 14 16 6 20 60 12 207 3 27 2 7 2 8 370 1.5 West 15 16 1 2 10 13 12 86 3 2 14 4 4 2 169 2.5 West 16 11 10 5 27 10 53 2 18 5 3 4 148 2.1 West 17 14 1 2 1 1 1 2 22 2.5 West 18 36 5 2 82 23 10 105 3 2 8 3 4 10 293 4.2 Total 312 60 9 274 209 150 695 28 14 164 4 78 40 59 2096 Table 2. Seasonal movement of all turtles by month. Data include painted turtles, snapping turtles, and unidentifiable turtles. Region Site May June July August September October Total # of Turtles Southeast 0 5 12 7 0 9 2 35 Southeast 1 8 5 2 0 1 0 16 Southeast 2 1 6 1 0 0 0 8 Southeast 3 0 0 0 0 0 0 0 Southeast 4 5 7 4 7 15 1 39 Northeast 5 12 26 7 5 21 2 73 Northeast 6 0 4 6 3 7 0 20 Northeast 7 0 2 0 1 0 0 3 Northeast 8 0 2 1 0 1 0 4 West 13 12 5 11 16 16 3 63 West 14 7 10 4 0 1 0 22 West 15 4 4 4 6 1 0 19 West 16 7 6 2 5 1 0 21 West 17 4 5 5 1 0 0 15 West 18 8 10 3 3 17 2 43 Total 73 104 57 47 90 10 381 Figure 1. a.-o. Turtle road mortality maps for 2018 by site. Labels indicate Control (a, g, k, l, m), Treatment (e, f, j, n, o) and Contingency (b, c, d, h, i) sites. In figures, red markers with “X” indicate deceased painted turtles, red markers with black dots “•” indicate live painted turtles, red with “U” indicate unidentified deceased species of turtles, and yellow markers with star symbols indicate deceased snapping turtles. Proposed fences are indicated by white lines in treatment sites. There were no turtles found at S Site 3 (d). a. Control b. Contingency c. Contingency d. Contingency e. Treatment f. Treatment g. Control h. Contingency i. Contingency j. Treatment k. Control l. Control m. Control n. Treatment o. Treatment Figure 2. Encounters by month of all identifiable turtles, including both dead and live individuals. Figure reflects total number of turtles by species: painted turtles (n= 312) and snapping turtles (n=60).