Counting bats as they leave roosts is the only way to begin to understand the numbers of various bat species living in our community. The identity of bat species at the roost may be determined by their echolocation calls or by analyzing the genetic record from guano samples. To tell if our bats are being affected by changes in their habitat or with the climate, some knowledge of their numbers as roost sites is essential. These numbers begin to give us a window into how many bats are using what types of habitats. Counting also helps us as landowners appreciate a species that greatly assists with bug control in our local environment and in addition enhances our familiarity with individuals that may share our immediate surroundings for 20-30 years.
Counting bats as they exit roosts at dusk gives an approximate number for the bats using these roosts. BC Community bat roost counts are done at least twice. The first count period is between June 1 and 21 before the baby bats are flying and the next period is July 21 to August 15 when both mums and pups are counted. More than one repetition of the count is helpful. Official BC count forms can be obtained at the BC bats web wage but on Denman DCA will take any bat roost counts that have:
- Time (begin & end of count),
- Roost description (g. bat house or where in building or type of natural roost)
- # bats seen leaving roost.
In many cases we can fill in the rest of the information needed for the official record. Please send any count results to firstname.lastname@example.org.
More information about the importance and results of these province-wide bat roost counts from 2012 -2016 is in the Annual Bat Count Summary 2017 may 2. (pdf 1 mb.)