+49 8772 8296 info@es-geht.gmbh

Today we want to introduce you to a private activity of our colleague Kevin, because he is doing bat monitoring. We find this quite interesting and asked him to describe what he is doing and how he got into it. Have fun reading!

How Kevin got into bat monitoring and how it enriches him in his work at Es-geht!

I started working in the field of ornithological surveys and bat surveys when I was a student and I still do it on the side. Working in nature has given me a lot of basic knowledge about the function of ecosystems and the anthropogenic influence on the environment. Functioning ecosystems and biodiversity promote resilience.

This sensitization is very important for me and finds connection in my present activity with the company Es-geht! Energiesysteme GmbH. We will integrate the environmental analyses into our concepts as far as possible. For example, a vegetation analysis was carried out on public areas as part of a contract and recommendations for action are currently being drawn up. The results will then be published on the project website (German).

Display of a Bechstein’s bat (Myotis bechsteinii) (Source)

Which species of bats are there and why are they so important?

The world of bats holds an important ecological role. In Europe, as nocturnal hunters, they play a crucial role in the regulation of insect populations and thus contribute to the maintenance of ecological balance. Bats belong to the order Chiroptera. With more than 1460 species worldwide, Chiroptera is the second largest group of mammals with the greatest biodiversity. Most bat species are insectivores, consuming up to 70-84% of their body mass in insects each night, sometimes >100%. Bats employ different hunting strategies depending on their foraging guild, with some species specializing in flying insects (flying hood bats) and others retrieving prey directly from foliage or the ground (gleaning bats). Several authors have reported on the vital ecosystem services of bats as pest controllers, which are beneficial to both ecosystems and farmers.

The myth of bats – and today’s approach

In the past, bats were often viewed by people with a mixture of fascination, fear and superstition. In many cultures, they were often associated with darkness, night, and mystery, leading to negative perceptions. Their nocturnal behavior and fluttering flight contributed to their perception as eerie. The mythological and folkloric background of many societies was often reflected in the way bats were interpreted. Some time-honored notions led to bats being mistakenly associated with vampirism. This was because there are some bat species that feed on blood, but these are actually a minority. The majority of bats feed on insects or fruits, which contributes to a healthy ecosystem. The bats’ appearance also contributed to their questionable reputation. Their wing structure, reminiscent of human hands, and their nocturnal activity reinforced the impression of the uncanny and the unknown. In some cultures, bats were associated with death and doom, contributing to their reputation as unlucky.

In recent decades, awareness of the need to protect bats and their habitat has evolved. Scientific knowledge and educational programs are attempting to overcome the prejudices of the past and promote understanding of the important role bats play in our ecosystems.

Display of a Western barbastelle (Barbastella barbastellus) (Source)

Kevin describes bat monitoring – what is it?

Bat monitoring refers to the systematic observation, recording, and evaluation of bat populations and behavior. It uses a variety of methods to gain insight into the lives of these nocturnal mammals. These include technologies such as ultrasonic detectors, which can record the ultrasonic calls of bats that are inaudible to the human ear. By analyzing these calls, scientists can draw conclusions about species identification, activity patterns, reproductive behavior and foraging.

Bat monitoring is an important part of ecological assessments in the field of wind power, as many bat species and their habitat are threatened.

Steps of bat monitoring
Collection of data
  • Mapping of potential roosts within 500m radius: the area is surveyed for potential roosts. Quarters surveyed and then recorded in the geographic information system (e.g., chipped bark, tree cavities, rock crevices, etc.).
  • Night surveys:
    • During periods April-May and August-October, bat calls will be recorded on selected transects within a 2000m radius using a batcoder.
    • In the period September-October, the area is surveyed for bat migration prior to the surveys (migration monitoring).
    • In the June-July period, walkovers will take place on the selected transects from sunset to sunrise. At the end of the survey period, swarm observation will be carried out 1 h before sunrise at the planned wind turbine site or in the immediate vicinity.
  • Bat trapping: in the period June-July nets will be set up at selected sites to trap bats. This is followed by the identification and documentation of the captured animals. In the case of species relevant to planning (e.g. pug bat or Bechstein’s bat), the females are preferentially transmittered. In this process, individuals attach a miniature transmitter to the dorsal fur of the bat, which emits radio wave signals at regular intervals.
  • Telemetry: after a successful night of trapping and the animals have been tagged, telemetry is carried out by two people at 5-minute intervals on the next day (or on the following two days). A line is then drawn in the geographic information software and the associated data entered into the shape file. The intersection of the two lines gives the approximate location of the bat.
Evaluation of data

Data processing: processing of collected data after the season (March-October).

  • Data from the mapping work provide approximate habitat structures.
  • Data from post-season surveys and trap nights: provide information on which bat species live in the area and to what extent. This is followed by visualization and species assignment based on contacts from the Batcoder .
  • The telemetry provides an insight into the hunting behavior within a geographical area of a particular species, which is an important component of an action analysis.

Based on the findings from the data, the preparation and finalization of the survey report follows in the “winter”. The protection of the bats includes not only the protection from the operated wind turbine, but also the destruction of the habitats.

What do you think about the bat monitoring of our colleague Kevin? Do you find such contributions about the activities of our workforce interesting and want more? Feel free to let us know.

Your Es-geht! Team