Driving Consultancy Success: Mapping Workflows for Consistent, Efficient and Defensible Bat Surveys
Introduction
February is an ideal time for Preliminary Ground Level Roost Assessments, when leaf fall improves visibility of trunks and branches. But cold fingers, short days and long site walks are not the conditions to be juggling paper forms (let alone trying to decipher hurried notes back at the office!). This is exactly when having a well-designed digital workflow really pays off.
In my early days of QGIS training with the FSC, I was lucky enough to be able to develop delegate core GIS skills in some fantastic locations, and had some truly memorable breaks to see limestone pavement and starling murmuration’s! One of the first GIS tutorials I designed for FSC was mapping Core Sustenance Zones (CSZs) for bats.
While my approach to training has evolved, I still regularly support ecologists working on bat surveys and reporting. And what hasn’t changed is the need for clear workflows that link desk study, field survey and post‑survey analysis into a single, defensible (think public enquiry) process. With a little knowhow, QGIS, the Mergin maps field survey app, and some great (open)data can support exactly that. So let’s dive into the spatial side of bat surveys.
Pre‑Survey Desk Study: Preparing for Surveys with Confidence
When a bat survey is triggered, the desk study is often where you first start to get a feel for the site. Before any kit is packed or access arranged, QGIS allows you to rapidly pre‑assess constraints, likely bat use, and survey effort, in a way that mirrors how ecologists already think about sites.
Key desk‑study tasks supported by QGIS include:
Site boundary and Zone of Influence (ZoI): Accurately digitise the red line boundary (RLB) and establish ZoI so you’re clear from the outset which features are genuinely relevant and which sit outside the scope of the survey.
Land ownership and access constraints: Map access points, land ownership parcels (from Land Registry data), and use LiDAR to asses terrain (could you get a Mobile Elevating Work Platform on site if needed?)
Understanding the built environment: Building age and structure type can be derived from Ordnance Survey’s National Geographic Database (NGD) and can give an early indication of roost likelihood; helping you judge survey effort before visiting site.
Proximity analysis: In a few clicks, measure distances to from RLB to:
Foraging habitats and commuting features like watercourses, woodland edge and hedgerows.
Statutory and Non-statutory sites.
Integrate relevant LERC species records with the Tombio plug-in.
Establish Core Sustenance Zones: Use buffer tools make it quickly to define Core Sustenance Zones (CSZ) for the particular bat species, and geo-processing tools to assess habitat availability in the CSZ.
Consistent Survey Design & Data Collection in the Field
Designing survey forms in QGIS and deploying them via Mergin maps ensures surveyors are prompted to record everything required.
Some benefits of digital field data capture include:
Standardised dropdown menus ensures roost indicators (droppings, staining, noises) are consistently recorded.
Mandatory fields ensure key attributes such as weather conditions are always included.
Reduced transcription errors, and no re‑entering handwritten notes.
Easier data sharing in response to public enquiries.
Ensure photos can be easily cross-referenced with survey locations.
Bluetooth GPS enables survey locations to be accurately mapped (and re-found!) even under canopy. Mergin automatically collects and stores the accuracy of the enhanced GPS in the attribute table.
Mergin synchronisation allows colleagues in the office to review the data and communicate with client in real time.
Where follow‑up surveys are required (e.g. via tree climbing or a mobile elevating work platform) a QGIS form can be set up to link information to the same point. This ensures a clear evidence trail.
Emergence & Activity Surveys: Making sense of Complex Data
Where Emergence surveys are required they increasingly rely on video recording, generating large volumes of data. AI‑assisted video analysis is starting to automate detection and flight direction and QGIS provides the natural environment for turning those outputs into clear, defensible maps. These help make sense of the data and communicate effectively to stakeholders.
QGIS can also help in various ways, such as:
Select appropriate locations for the static detectors based on features (and to effectively hide the kit!).
Map exact roost features, access points to roosts, and camera locations, and link clips from the video and sound files directly to them.
Visualise flight directions: use arrows, which can be categorised by species and weighted by frequency, to indicate predominant flight paths.
Transect design: Prepare routes of similar length in QGIS, and use Mergin GPS tracking to record actual walked routes for full transparency.
Static detectors: create heat maps, or proportional symbols, to reflect activity.
Set up template maps and map themes for consistent and efficient reporting.
Conclusion
Bat surveys are inherently complex. They span seasons, methods and survey types, generate large volumes of data, and are carried out under real-world pressures like weather, access and time. None of that is going to change.
What can change is how well the tools support the ecologist doing the work. Used together, QGIS, Mergin Maps, and a wealth of (open)data, provide a clear, connected workflow from desk study to reporting; reducing duplication, improving accuracy and making survey data easier to defend.
For ecologists to get maximum benefit from the latest mapping technology I recommend context specific on-demand training videos and dedicated, responsive support for hands-on help. When ecologists understand the workflow, and trust the tools, they can focus on what really matters: reading the site and the species behaviour.
If you would like to chat about how Spatialsesh can support you, get in touch here.