Changes in population size of bats at a hibernaculum in Alberta, Canada, in relation to cave disturbance and access restrictions

  • Published source details Olson C.R., Hobson D.P. & Pybus M.J. (2011) Changes in population size of bats at a hibernaculum in Alberta, Canada, in relation to cave disturbance and access restrictions. Northwestern Naturalist, 92, 224-230.


This study is summarised as evidence for the following.

Action Category

Impose restrictions on cave visits

Action Link
Bat Conservation
  1. Impose restrictions on cave visits

    A before-and-after study in 1983–2009 at one cave in the Rocky Mountains, Canada (Olson et al 2011) found that enforcing restrictions on cave visitors resulted in more bats hibernating within the cave. An average of approximately 450 bats/year hibernated in the cave before restrictions were enforced, and 650 bats/year after. The cave (length 2791 m, depth 220 m) was highly popular with recreational visitors. In 1997, seasonal access restrictions were imposed. In 1998, the area was established as a National Park and signs were erected to inform the public about access restrictions. Active enforcement to restrict recreational visitors in winter months began in 2000. An annual census of visual counts of hibernating bats was carried out in 11 chambers within the cave from 1983 to 2000, followed by a census every other year until 2009.

    (Summarised by: Anna Berthinussen)

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