Effectiveness of Ledges in Culverts for Small Mammal Passage

Details

• Creators:
  Meaney, Carron A. ; Bakeman, Mark ; Reed-Eckert, Melissa ; Wostl, Eli
• Corporate Creators:
  Meaney & Company ; Walsh Environmental Scientists and Engineers ; Ensight Technical Services, Incorporated ; Bear Canyon Consulting, LLC ; University of Colorado at Denver
• Corporate Contributors:
  Colorado. Department of Transportation. Applied Research & Innovations Branch ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  Bridges Cameras Corridors Culverts Ecoculverts, Preble's Meadow Jumping Mouse Habitat Habitat Fragmentation Mammals Ramps Rodents Traffic Mitigation Wildlife Crossings

  More +
• Publication/ Report Number:
  CDOT-2007-9
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Colorado
• Edition:
  Final Report
• Corporate Publisher:
  Colorado Department of Transportation. Applied Research & Innovations Branch
• Abstract:
  Ledges were installed in six culverts in Boulder County, Colorado, to test their ability to facilitate small mammal movement under roads and to determine whether Preble's meadow jumping mice (Zapus hudsonius preblei) would use such ledges. Ledge use was measured by recording photographs of mammals on the ledge with motion-detecting cameras. Ledges connected to the streambank with removable ramps, which served as a proxy for rendering the ledges accessible in order to test whether there was more usage when the ramps were on (ledges accessible) than when they were off (ledges inaccessible). Nine mammal species were captured using the ledges in 705 photographs during the study spanning two summers, 2005 and 2006. Preble's meadow jumping mouse was photographed on the ledge only once during the pilot and three times during the active study. There were 443 photographs of mammals on the ledge with ramps on and 262 photographs with ramps off. Significant differences were found among the six culverts and between ramp conditions. The ledges appear to present desirable passageways even with the ramps off, to the extent that small mammals will climb up concrete walls to access them. Culvert dimensions and vegetative cover did not show statistical correlations with the number of photographs, possibly because of the small number of culverts.
• Format:
  PDF
• Funding:
  32.41
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:ce1888806322ddf887bb0d5af7cf45f587fed98094169a4fa4efb31b36a2409634dd5ce57f6774cb175c73f8f17fd5243ad76341593c5dc67c67a929561c8c98
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/93059/dot_93059_DS1.pdf
• File Type:
  [PDF - 1.37 MB ]