Executive Summary
Electric power line infrastructure can adversely impact bats due to tree clearing associated with a wide variety of activities.  This can include tree removal, crushing bats, flushing bats, noise, and chemical contaminants, which may kill, wound, harm, harass if they are present during the work.  Clearing vegetation is the most direct threat when it involves trees suitable for roosting.  A key to any new project is to begin planning as early as possible to allow for the appropriate measures required to avoid and minimize impacts to bat species.  Aiming for winter tree clearing between October 1 through March 31 is one of the prime opportunities to avoid these impacts, however there are times when this is not feasible.  When coops are unable to utilize the winter clearing season, the flowchart below will help in navigating the regulations and ensuring your coop is compliant with the Endangered Species Act (ESA) utilizing proper project screening, habitat assessments, Summer Presence/Absence Surveys, and if needed, hibernacula surveys.

Range-Wide Survey Guidelines
Bat survey guidelines are updated annually.  Therefore, providing survey guidance in this document, the guidance would quickly become outdated.  To ensure your coop is reviewing the most up-to-date information, ensure that the latest survey guidance is reviewed, which can be found here.   One item to understand is that for some projects, surveys may require modification and your coop should work with the state U.S. Fish and Wildlife Service (USFWS) Field Office (FO).  Here is a link to the Missouri USFWS FO and to the Oklahoma USFWS FO.

The survey season runs from May 15th through August 15th each year, so each coop will want to consider this for their project planning.  Although the survey guidelines are title for the Indiana Bat, the protocols are also used for the Northern long-eared bat (NLEB) with only some minor differences, such as 1.) definition of suitable summer habitat 2.) weather-related exceptions, and 3.) no internal hibernacula surveys.

Indiana Bat Avoidance, Minimization, and Conservation Measures

The following flow charts provide a reference in navigating the regulations associated with the Indiana bat, Northern long-eared bat, and new construction:

 

 

 

Measures to Avoid and Minimize Impacts to Bats in Known or Presumed Occupied Caves/Winter Habitat

  1. When burning brush piles within 0.25 miles of known or presumed occupied hibernacula from August 15 to May 15, the brush piles should be no more than 25 feet by 25 feet, and should be spaced at least 100 feet apart, and located at least 100 feet from known hibernacula entrances and associated sinkholes, fissures, or other karst features
  2. No woody vegetation or spoil (e.g., soil, rock, etc.) disposal within 100 feet of known or presumed occupied hibernacula entrances and associated sinkholes, fissures or other karst features.
  3. Protect potential recharge areas of cave streams and other karst features that that are hydrologically connected to known or presumed occupied hibernacula by employing proper Spill Prevention, Containment and Control, as well as, proper Stream and Wetland Crossing best management practices.
  4. Maintain a silt barrier around the rim of the protection area until all disturbed areas are vegetated.
  5. Provide a sedimentation basin at all point discharges with more than 1 acre of drainage area.
  6. Restrict use of herbicides for vegetation management within the known or presumed occupied habitat to those provided by USFWS (appropriate for aquatic use and unknown to be toxic)
  7. Protect known mapped recharge areas of cave streams and other karst features, with buffers of 300 feet around these features in all work areas.  Clearly mark the areas in the field with signs and/or highly visible flagging until construction-related ground-disturbing activities are completed.
  8. Excavation adjacent to karst features, place spoils on the up gradient side of the excavation so that if any erosion takes place the stockpiled soil will flow back into the excavation and not down gradient towards the karst feature
  9. Educate Operators, employees, and contractors (working in areas of known or presumed bat habitat) on the biology of Indiana bats, NLEB, and OBEB (if in habitat area), activities that may affect bat behavior, and ways to avoid and minimize these effects.

(NiSource Multi-Species Habitat Conservation Plan)

Key Terms and Definitions

Diameter Breast Height (dbh) – is tree diameter measured at 4.5 feet above the ground.

Figure 10: Proper method for measurement of diameter-at-breast-height (dbh) (https://www.researchgate.net/figure/255262269_fig11_Figure-5-Proper-method-for-measurement-of-diameter-at-breast-height-DBH-of-the-tree)

Foraging Habitat – A forested stand with trees greater than or equal to four inches dbh with no preferred tree species or suitable snags

Forested Stand – a contiguous forested area in the permanent ROW and temporary workspaces comprised primarily of trees greater than or equal to four inches diameter breast height (dbh)

Maternity Roosting Habitat – A forested stand with one or more trees greater than or equal to nine (9) inches in diameter at dbh that are either preferred tree species with greater than or equal to 30 percent exfoliating bark or suitable snags.

Non-maternity Roosting Habitat – A forested stand with the following characteristics:

  • No trees that are greater than or equal to nine (9) inches dbh that are either preferred tree species with greater than or equal to 30 percent exfoliating bark or suitable snags, and
  • Trees greater than or equal to four inches dbh that are either preferred tree species or suitable snags

Preferred Tree Species – Shagbark hickory, cotton wood, white oak, maple, American elm, shortleaf pine, and other oak species. Primary maternity roost trees are maternity roost trees that are 16” dbh and greater

Snag – a standing dead tree with greater than or equal to 30 percent exfoliating bark, crevices, or holes.

Links for Bat Consultation and Additional Information

  1. USFWS IPaC - https://ecos.fws.gov/ipac/
  2. White Nose Syndrome (WNS) - https://www.whitenosesyndrome.org/
  3. Indiana Bat Summer Survey Guidance - https://www.fws.gov/midwest/endangered/mammals/inba/inbasummersurveyguidance.html
  4. Section 7 Consultation - Section 7 Consultation Step-by-Step Guidance
  5. 4(d) Rule for Northern Long-Eared Bat - https://www.fws.gov/midwest/endangered/mammals/nleb/4drule.html