Abstracts

Keynote: Radiotracking bats - where have we been and where to next? - Professor Fiona Matthews, University of Sussex

Radiotracking has revolutionised our understanding of animal behaviour. But bats are the ultimate challenge. Small, nocturnal and fast, they push radiotracking technologies - not to mention its human operators - to the limit. In this talk I will be reflecting on how far we have come since the early days, when radiotags were first miniturised sufficiently to attach to bats, and thinking about where we go next. This is an exciting time, with rapid advances in areas such as GPS tagging and static radiotracking networks. Alternative technologies such as PIT-tagging are also emerging. I will therefore conclude by suggesting how bat researchers might go about making the most appropriate choice of technique.

Improving your analysis – pros and cons of different analyses for home ranges and how to collect bat fixes effectively for analysis - Ian Davidson-Watts, Davidson-Watts Ecology

Wildlife Drones: innovative technology for radio-tracking up to 40 bats simultaneously - Dr Debbie Saunders & Paul Sinclair
Email: paul@wildlifedrones.net

Managing threatened bat species, and understanding where they roost and how they move across the landscape is critically important for making effective management decisions. However, tracking technologies such as satellite and GPS tags that enable remote data collection remain too large and heavy for microbats. Therefore, microbat tracking is typically undertaken using Very High Frequency (VHF) radio-transmitter tags and hand-held receivers, which is very labour intensive and time-consuming when tracking highly mobile animals. However, when using Wildlife Drones aerial radio-tracking technology, up to 40 bats with unique VHF transmitter frequencies are tracked simultaneously from the air. We will share insights from our journey developing Wildlife Drones’ world-first technology, as well as explain how it works and what the data looks like when tracking highly mobile species. We will also provide examples of projects where Wildlife Drones’ radio-receivers have been used to track bats at roosting sites, when foraging at night and even migrating. Such innovative technology provides new opportunities for improving and expanding bat research, monitoring and conservation projects globally.

Industry Insights: Understanding GPS, VHF, and Satellite Tracking Technologies for Bat Conservation - Sarah Deans, Lotek

Bat tracking technologies have witnessed remarkable advancements in recent years, revolutionizing our ability to comprehend the ecological roles of these elusive nocturnal mammals. In the modern age researchers have access to more tools than ever before including VHF, GPS and Satellite technology. The data gathered from these devices can be combined with other information such as acoustic monitoring and environmental data to build comprehensive conservation strategies. Focusing on tools already being used by researchers including GPS, VHF, and Argos satellite-based tracking technologies this presentation aims to be a guide to help researchers navigate all the options open to them for bat tracking projects. As professionals working at the forefront of wildlife tracking technology, we are able to offer a comprehensive overview of the principles, capabilities, and real-world applications in studying bat ecology. Join us as we explore this fascinating intersection of technology and conservation, and how it is shaping the future of bat conservation worldwide.

Before, During & After - James Aegerter, Animal & Plant Health Agency

From concept to communication, a radio-tracking study entails a sequence of choices and decisions affecting tasks: Formulation, Planning, Training, Tracking, Analysis, Inference, and Dissemination.

Here I’ll focus on a few of these and their interdependencies, suggesting that the whole process might be best thought of as circular and backward. For every task choices before, affect the during which define the after.

I’ll discuss recording data in the field, and why I’ve been doing it a little different over the last few years. I’ll discuss formulating a study and why what happened before is important. I’ll suggest evidence from two previously unpublished studies may give pause for thought, one positive and intriguing, and one less so.

Fit For Purpose: techniques to improve data collection and bat welfare in radio-tracking studies - Dr Charlotte Packman, Ecology Resources / University of East Anglia

Radio-tracking of microbats is widely used by researchers, conservationists and ecological consultants to advance understanding of bat ecology and behaviour, inform and test conservation measures and as a basis for Ecological Impact Assessments affecting important bat habitats and rare species. The latter, in particular, can have significant legal (for protected species), conservation (for rare species) and cost implications. Such “high stakes” scenarios can have major consequences for bat conservation, meaning that the accuracy and quality of the underlying data is paramount.

Through radio-tracking of >400 microbats of a range of different species in both the UK and abroad, we have refined field techniques and developed safe and effective protocols for robust data collection, suitable for a wide range of applications. In particular, methods have been refined to enable detailed,
high resolution data collection for fast-flying species with large home ranges.

High quality data collection relies on appropriate training of the data collection team, effective radiotracking skills and methods, over-coming the particular challenges of radio-tracking fast-moving and wide-ranging bats at night (using a hybrid approach of ‘homing-in’/’close-approach’ and triangulation) and suitable data recording, using simple, readily available tools and technology. Methods to improve bat welfare (including tag/transmitter attachment) and reduce impacts on tagged bats (and, where
applicable, their offspring) are also discussed.

Specific issues addressed include:

• Considerations for minimising risks when radio-tagging bats
• Getting the most out of radio-tracking data: tried and tested methods for accurate, high resolution data collection
• Challenges and solutions for effectively tracking fast-flying species with large home ranges
• Fit for purpose: ensuring the data collected address the project aims and questions

The methods developed have proved very successful in ensuring high quality and consistent data collection as well as maximising the information that can be obtained from each radio-tagged individual whilst minimising risks to bat welfare. This enables better and more cost-effective conservation outcomes for bat populations that will be significantly impacted by measures and recommendations resulting from the radio-tracking data.

Locating bats when 'standard' techniques can't be used - Nick Tomlinson, Dorset Bat Group

Nick will give a brief overview of the techniques they have developed as part of their projects in Dorset.

A case study for implementation of novel remote automated radio-tracking on monitoring projects and how else it can be used - Charlotte Wevill and Chris Kerfoot

Radio-tracking is a powerful methodology used to collect information on flightlines, roosts and habitat use by bats, it allows for a greater understanding of how bats utilise landscape and can determine conservation requirements, predict impacts and monitor effectiveness of interventions. However, conventional bat radio-tracking methods are labour-intensive requiring long nights of field work with associated safety risks and limitations to data collection.

As part of a long term monitoring project for a commercial project we designed and implemented an approach for comprehensive assessment using remote radio-tracking technology and interpretation of results . The logger system technology manufactured by Plecotus solutions, uses a remotely accessed and automated radio-tracking logger system to monitor the movement and roosting behaviour of radio-tagged bats. We have completed three years of monitoring so far within the Colne Valley during construction of HS2 Phase One, which has generated extremely powerful results and provided wider insights into applications for assessment, consenting, licencing and monitoring of large landscape scale projects. HS2 have a strong commitment to long-term monitoring and innovation and supported this approach, testing and refinement of it. This approach has proven so effective it has been rolled out on to other projects with different aims and has highlighted gaps in current industry understanding of bats and approaches to assessment and licensing.

The logger system used at the Colne Valley comprises six loggers deployed throughout the licence area collectively providing coverage over approximately 800ha. Each unit consists of a data-logger connected to four directionally sensitive aerials mounted on a mast. The loggers are battery and solar powered and fitted with a SIM card to allow remote configuration and data download. Each logger records tag frequency, direction and signal strength when a tag is within range. The loggers record data continually for the life of the tag and record all tag frequencies simultaneously. The purpose built interface app is then used to download the data and match up bearings recorded on different logger units to obtain accurate timestamped triangulations of the bat’s location. This allows flightlines to be created resulting in a high-resolution map of how bats use the landscape.

Location data is collected from all tags continuously and simultaneously, providing detailed information on bat movements and roosting behaviour as well as providing insights into interactions between individuals. The methodology used to apply the system was carefully assessed, discussed and agreed with Natural England and other interested stakeholders (The Wildlife Trust) before being implemented.

Compared to conventional radio-tracking techniques, where it usually possible to collect only several hundred triangulations over the lifetime of a radio-tag due to cost, time, labour and access constraints. This system is not limited by those resources so collects tens of thousands of data points on unlimited number of tags. This maximises the amount of data collected for each bat tagged, which is a key welfare consideration for this type of work.

The costs of installing the system and data analysis are lower than conventional techniques and there are significant safety benefits from reduced night work on construction sites. The conservation and commercial applications are therefore powerful, providing vast amounts of data in a cost effective and safer environment than with manual radio-tracking surveys. There is additionally capacity for real time feedback on the construction impacts on bats and facilitates agile responses in implementing mitigation measures for impacts such as lighting and noise. It has the potential to detect real time changes in population movements in response to construction activities and mitigation measures.

Based on the success we found in using this method as part of monitoring, this year we implemented this approach on several other large infrastructure projects to obtain baseline data as part of landscape scale approaches to impact assessment and licensing. We are also considering this approach for other protected species for the same projects. The data obtained means that objectives over the lifetime of the project can considered at the earliest phase of design and accounted for within the masterplan and throughout construction and operational monitoring. The outcomes of this work has also highlighted some gaps in current understanding of how bats use features in the landscape, their relative importance for favourable conservation status and has stimulated discussion around how licensing could be approached on landscape scale projects. The information gathered from our work, could help improve industry best practice, provide clearer direction on how to plan and determine objectives for assessment and monitoring throughout the lifetime of a project by allowing greater understanding how bats may be impacted and how they respond to change in their environments.

Disco bats and glittery poo - James Shipman

James has been monitoring the populations of soprano pipistrelles over the last 10+ years in West Berkshire. Within one woodland there are two separate populations within the bat box monitoring scheme that never move between the two split sides of woodlands. By using UV powder James is looking to explore the movements of the two populations between these two woodland areas but also within potential tree roosts via the use of UV light. The use of UV powder is also being used to see the movement of noctule bats across southern areas of the project boundary and in the next coming years radio tracking will be used to determine the wider use of the landscape.

The continuous evolution of GPS tracking technology - Gary Brodin, PathTrack

Using GPS and an Aircraft to track bats - Geoff Billington, Greena Ecological Consultancy

Showing how we have used GPS tags to find flight routes, foraging areas and roosts of Greater horseshoe bats in North Devon. Using an aircraft to locate tagged swarming bat roosts in Suffolk

Advanced Automated Bat Tracking: From presence-absence telemetry to position finding - Jonas Höchst, Jannis Gottwald, trackIT Systems

The trackIT System is an automatic radio-tracking system that enables continuous recording of more than 60 tagged individuals concurrently. Signals are sent to a remote server in real-time, where they are processed into outputs such as localisations, body temperature or individual activity classifications and are visualised as interactive graphics in real-time.

The software and the hardware of the system are open-source and the system itself has been deployed at more than 600 sites to track small scale movements of birds, snakes and small mammals including over 500 bat individuals of 15 species.

Our talk introduces the latest advancements in the trackIT system. We explore distance-based telemetry with omnidirectional stations, employing models to estimate distance from signal strength and presence-absence analysis, i.e., tracking presence within station radii throughout the night. For spatial localization we present two methods: First, using directional stations, angles can be determined with signals received from the two antennas with the highest received signal strength, in addition to distance measurements. Second, our new Antenna Beam Position Finding method uses weighted average reception ranges based on signal strengths from all antennas that received a signal.

Position finding with the trackIT system is achieved through two options: 1) multilateration of transmitters based on distance information from multiple stations, and 2) weighted averaging of multiple station points based on Antenna Beam positions.

In addition, we show possible applications of the system and results based on various projects from the last 2 years, including the tracking of bats in road construction and wind power projects as well as examples of other species groups in nature conservation projects.

Using MOTUS telemetry to study migratory behaviour of Nathusius’ pipistrelle - Jane Harris, Norfolk and Norwich Bat Group

The talk will describe all the steps required to use the MOTUS wildlife tracking system including equipment, tag ordering and specifications, MOTUS receivers, using the MOTUS website for setting up projects and data analysis, Ofcom licences and practical considerations for the fieldwork.

Too cold to wake up? Uncovering the winter foraging activity of the greater horseshoe bat, Rhinolophus ferrumequinum, using a novel radiotracking technique - Katie Allan, University of Sussex and Vincent Wildlife Trust

Obtaining detailed information on the movement of bats is difficult using current radiotracking methodologies due to their small size, fast flight, and complex life-history strategies. Tracking during the hibernation period adds a further level of complexity, owing to longer night lengths and shorter activity periods during this time. Identifying foraging and roosting locations used during the winter months is a key knowledge gap that must be filled to develop effective conservation strategies for the greater horseshoe bat, Rhinolophus ferrumequinum, a species that is known to feed and switch roosts regularly during the winter. Using a static automated radio-telemetry network, which is compatible with the Motus Wildlife Tracking System, we studied the winter foraging activity of the greater horseshoe bat in the UK. By deploying a network of 12 radio stations and 20 smaller ‘nodes’, we tracked 62 individual bats over two consecutive winter seasons (2022-2024). Using this large dataset, we investigated whether emergence times and activity patterns were predicted by individual factors (e.g. sex, age, and body condition) or environmental cues (including ambient temperature, precipitation, and lunar cycles). To the best of our knowledge, this is the first study to observe individual temporal and spatial patterns of activity in this species over the winter and illustrates the utility of new remote-sensing technologies to provide fundamental insights into the behaviour and ecology of bats.