OHIO DEPARTMENT OF TRANSPORTATION BAT GATE CONSTRUCTION

Transcription

1 OHIO DEPARTMENT OF TRANSPORTATION BAT GATE CONSTRUCTION

2 ABANDONED RAIL TUNNELS REDISCOVERED During survey work for the Harrison County Road 51 bridge replacement project, the first of the abandoned rail tunnels (Tunnel 9) was found. Ohio Rail Development Commission notified ODOT Office of Environmental Services (OES) that 3 additional abandoned rail tunnels are located in Harrison and Jefferson Counties (Tunnels 7, 8 and 10). ODOT OES field reviewed the tunnels and found bats roosting in all abandoned rail tunnels. The construction of Tunnel 9 in

3 TUNNEL HISTORY Steubenville Indiana Railroad These tunnels were constructed in 1850 by the Steubenville and Indiana Railroad Rail laborer worked day and night from both ends and a shaft was sunk in the middle to allow 3 work groups to labor constantly until the tunnels were completed. In 1949, the tunnels were bypassed and new cuts were made near the tunnels. On average, these tunnels are 2,000 in length. Bowerston Tunnel, now know as Tunnel 10 3

4 ABANDONED RAIL TUNNELS 7, 8, 9 AND 10 Hand laid brick interior of Tunnel 9 4

5 TUNNEL 7 In the 1950 s, the abandoned tunnels were closed off with dirt or concrete blocks. Vandals smashed through the concrete blocks to gain access to the tunnels. Tunnel 7 is inundated 5

6 TUNNEL 8 Front and Rear Entrances Vandals neatly smashed doorway in both the front and rear entrances of Tunnel 8 6

7 TUNNEL 9 Front and Rear Instead of concrete block, Tunnel 9 entrances were filled with dirt. 7

8 TUNNEL 10 The rear entrance is completely filled with dirt. Tunnel 10 concrete blocks are mostly intact in the front entrance except for a small opening on the right side of the tunnel 8

9 2016 HIBERNATING BAT SPECIES AND POPULATION SURVEY Location and Species Tunnel 7 93 Big Brown Bats and 3 Tricolored Bats Tunnel 8 19 Little Brown Bats and 1 Tricolored Bat Tunnel Little Brown Bats and 9 Tricolored Bats Tunnel 10 1 Big Brown Bat, 20 Little Brown Bats, 4 Tricolored Bats and 1 Northern Long Eared Bat Two Tricolor bats found in Tunnel 9 9

10 BATS STATE AND FEDERAL PROTECTION STATUS Listing Northern Long Eared Bat Federally Threatened Ohio Endangered Tricolored bat Petitioned for Federal Listing Ohio Species of Concern Little Brown Bat Ohio Species of Concern Big Brown Bat Ohio Species of Concern Little Brown Bat collected from Tunnel 9 being weighed, measured and banded 10

11 OTHER SPECIES USING THE TUNNELS Long Tailed Salamanders Spring Salamanders Red Back Salamanders Red Spotted Newts Leopard frogs Phoebes Mole Crickets Raccoons Deer Spring Salamander found in Tunnel 9 11

12 TUNNEL 9 UNIQUE DISTINCTION WNS has decimated bat populations in Ohio and North America Little Brown Bats were once the most common bat in Ohio. Their Ohio population was estimated over 500,000 just 10 years ago. Sadly with only 217 Little Brown Bats hibernating in Tunnel 9, this tunnel holds the second largest known population of Little Brown Bats in Ohio! Ohio is endangered of losing all hibernating species of bats. Ohio has seen a 100% mortality rates in some known bat hibernaculas. Little Brown Bat 12

13 ODOT PROPOSES GATING TUNNELS FOR BAT MITIGATION CREDIT USFWS approved Bat Mitigation Credit for gating abandoned rail Tunnels 7, 8, 9 and 10. Tunnel 10 contained a hibernating Northern long-eared bat (Federally Threatened) Tunnels 7, 8, 9 and 10 contained hibernating Tricolored bats (Petitioned for Federal Listing) Protecting bat hibernaculas are a Section 7 Endangered Species Act Conservation Measure. Hibernaculas are a critical life component and the rarest habitat type for bats. 13

14 BAT GATE DESIGN FOR TUNNEL 9 14

15 BAT GATE DESIGN TO PROTECT HUMANS AND BATS Dangers to bats Dangers to humans Humans White Nose (fungus) Syndrome Bat bones found in Tunnel 9 15

16 TUNNELS 9 AND 10 WINTER TEMPERATURES AND BAT SURVIVAL STUDY Constructed Hypotheses: Do very cold bat hibernaculas experience less WNF infection due to very cold hibernating temperatures Tunnel 9 Temperatures in Tunnel 9 were found be to 3 7 C above freezing. Colder temps slow WNF growth Deep long torpor pattern Bats in Tunnel 9 survived the winter Tunnel 10 Temperatures in Tunnel 10 were found to be C above freezing. Warmer temps allowed for WNF growth More wakeful torpor pattern All bats in Tunnel 10 died of WNS before winters end 16

17 TUNNEL 9 MINIMAL WNF INFECTION All bats from Tunnels 9 and 10 were infected with WNS, however; bats in Tunnel 9 showed promising signs of a minor WNF infection. WNF glows orange in the presence of UV light. 17

18 TUNNEL 9 WITH THE VERY COLD HIBERNACULA DATA OF WOODWARD CAVE IN PA In 2010, Woodward Cave in Pennsylvania was temperature modified to create a Very Cold Bat Hibernacula. Temperatures drop to below 5 C in the winter. In 2011, Woodward Cave was gated, it contained only 28 hibernating Little Brown Bats. The 2017 winter census found 308 hibernating Little Brown Bats. Probable Conclusion: Bat are maximizing WNS survival by slowing fungal growth and maximizing the ability of save energy during the winter. Woodward Cave, PA 18

19 ODOT IS PROPOSING MODIFICATIONS TO THE GATING OF TUNNELS 7, 8 AND 10 TO CREATE ADDITIONAL VERY COLD HIBERNACULAS IN OHIO ODOT OES is working with Ohio University to determine what techniques may work to reduce winter temperatures of Tunnel 7, 8 and 10 (pictured). Modifications may include: Creating a cold sink to trap cooler air. Insulating the block wall with dirt Increasing opening size Reduce opening size Adding additional openings Tunnel 10 19

20 BAT GATING SUCCESSES AND CHALLENGES Successes Challenges Ohio Department of Transportation is preserving the second largest hibernacula of Little Brown Bats in the State of Ohio. Ohio Department of Transportation is experimenting with a brand new technique that may reduce WNS in Ohio bats. Very Cold Hibernacula to reduce WNS is relatively unstudied. Modifying abandoned rail tunnels temperature is unprecedented. Tunnel sites are isolated. Ohio Department of Transportation will receive bat mitigation credit for preserving federally listed bat hibernacula habitat. 20

21 ABANDONED RAIL TUNNEL 9 CONSTRUCTION Westside Opening of Tunnel 9 Bat Gate Nearing Completion A small access door and lock will be placed in the center of this 18 square foot bat gate. This gate will be completed in approximately a week and a half. 21

22 ABANDONED RAIL TUNNEL 9 CONSTRUCTION Eastside Opening of Tunnel 9 Bat Gate Completed This 12 square foot square gate took a 3 man crew approximately one day to construct. 22