Fill in the Protocol of observation


Welcome to our website, which name can be translated like “Bats on trip”, because emergence from roost and trip has very similar shape of words in Czech language. This website was created to collect data about emergence behaviour in various species of bats. We will be pleased to get new observations from all over the Europe and maybe the world from you in section Observation. These data will be placed in database and will be used for further research of ethology of these flying creatures.

What is it good for?

Collecting data of emergence activity in bats is very time-demanding. For good research there should be more then dozens of datasets, which is above our strength. Until last years there were many of researches on this topic, but the intervals of record were 0.5, 1 or more minutes. In some researches there occurs also 5 minutes interval. I found a strong effect of inaccuracy in comparison with short intervals. That is the reason why I try to collect more detailed data with interval of 1 second only. With this interval we can also inspect clustering behaviour in response to predatory pressure.


Ethology is biological scientific discipline. Its main interest in animal behaviour helped people to understand animals as living creatures thinking in similar way as us, people. To main personalities bound with ethology are Jane Goodall, Konrad Lorenz or Zdeněk Veselovský.

Back to the founder of ethology – Konrad Lorenz – which also was an excellent psychologist and physiologist – we want to remind all batwatchers of his publication “Civilized Man’s Eight Deadly Sins”. Now, you can read all of sins, which Lorenz mentioned in his publication and you can make your own opinion: Was he in 1973 right?

  1. Overpopulation
  2. Devastation of environment
  3. Humankind competing against itself
  4. Emotional entropy
  5. Genetic decay
  6. The break with tradition
  7. Indoctrinability
  8. Nuclear weapons


In this section we are presenting four most abundant species of bats living in the Czech Republic. The goal of this website is also to show bright and positive sight of living next to bats because citizens tend to have a negative opinion to these creatures.

Common noctule

(Nyctalus noctula)

Netopýr rezavý

Common noctule is one of the largest middle-european bat species. Females form maternal colonies counting 20-100 individuals during late spring. The reasons for this behavioural adaptation are thermoregulation in roost, decreased risk of predation during emergence eg. Maternal colonies can be found in old oak trunks or under plating on panel houses. Common noctules are one of few bat species that can be heard by human ear. Sound they are producing is similar to creaking of the door.

Serotine bat

(Eptesicus serotinus)

Netopýr večerní

Serotine bats are known for their early emergence from roost. This fact also reflects their Czech name, which is translated as “evening bat”. Referring to CATTO et al. 1994, first bat emerges averagely 14 minutes after sundown. Females leave their offspring in roost and forage. This species during season changes foraging strategy and can use all 3 main strategies: aerial hawking, gleaning and short flights.

Common pipistrelle

(Pipistrellus pipistrellus)

Netopýr hvízdavý

Common pipistrelle belongs to small bat species they form large maternal colonies averagely consisting of 20-30 individuals. It is no exception to observe colony as large as 100 individuals. Biggest ones can have 500 females at the start of the breeding season so at late summer it can double itself in count. Common pipistrelle prefers heterogeneous landscape with riparian habitats.

Soprano pipistrelle

(Pipistrellus pygmaeus)

Soprano pipistrelle is a sibling species to common pipistrelle. It means that at first sight and most likely also on second sight you could not spot the difference between these 2 species. The main difference is in frequency of their echolocation and connectedly to it also their foraging and feeding strategy. This species is edge specialist. It means that this species forage preferably on the edge of the crowns of trees or forests e. g. Its preferred prey are mosquitoes and Simulium - annoying and disease transferring insect. And that’s nice positive ecological service for people.


Just to explain the difference between two language versions: This website in Czech version is focused on community science. It means collecting data from non-scientific observers that just like nature and bats specially. English version is mainly focused on scientific community but tries to show also the popularization side.

Watch bats with us!

If you were also so passionate with bats as we are, let's do some citizen science! Bats are fascinating but also neglected animals. There is a plenty of ways to watch bats, but main topic of this website and research is emergence sctivity in bats. The easiest way is to watch them in city environment. There we can watch dark bodies of bats conrasting with light color of houses or sky.

Guide for observation

If you are willing to be amateur ethologists or chiropterologists, it will be useful for you to check some tips. Maybe it will prevent negative control of the colony. Anyway this site is focused on emergence of bats from their roots, so emerge also and go out to watch bats with


Take notes from protocol of observation on the paper (available here). Your phone will be used for simple evidence of emergence activity. Download some of many stopwatch applications. For example Hybrid Stopwatch  (available here) has an ideal environment. Exact procedure is described in next section.


Do not go watch bats unnecessarily. Bad weather (which means strong wind and/or heavy rain) can lead whole colony to decision to stay in their roost. Their prey does not fly in these conditions also.


If there is cloudy weather, bats may emerge from roost earlier. Keep it in mind.

Guide for observation

Before the observation starts, please check if there are some predators, how the weather is and fill these prescribed information in in the Protocol of observation. This document is also available in English in both, online and offline (print) version. Please, also take a photo of emergence hole.

The observations have to be concrete in time. For this reason, we gently ask you for precisely timed start. The first event in time 00:00:00 should be equivalent to a whole minute, for example 20:46:00 (8:46 PM). Just press the start when the minute changes. Any other event, in Czech version of applications called “kolo” should be equivalent to one emerging bat. When there are more bats in one time, press it twice or more times, depending on the number of bats emerging in this time.

We recommend one concrete application for cell phones with Android OS.

First one: Hybrid Stopwatch (available here)

Introduction to using this app (follow the images as the numbers shown in brackets).

At first (1), hit the start button (in green circle), please pay attention to press it when the time is HH:MM:00. Then, (2) when every single bat emerges the roost, hit the flag button. When there are emerging more bats at the time, hit the flag in exact amount of repeat. At the end of observation press stop button. For sharing, hit the button on upper left (3) and choose “Kolo” from the list (4). Hit the share button on upper right (5).Choose “Text” and “.TXT” and press OK (6).Choose you e-mail application (7) and send it to (8).

Protokol o pozorování výletové aktivity netopýrů

Do you know about some colonies living in czech housing estates? You can also help us!
Protocol for observation is available for download here. („Protocol of observation.pdf“)

Basic information

Weather during observation

Speed of wind

Occurrence of predator or concurrent