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Woodroffe, R.

Publications and source records attributed to Woodroffe, R..

2 recordsLinked to original sources

Data-driven Analysis of Fine-Scale Badger Movement in the UK

Understanding animal movements at different spatial scales presents a significant challenge as their patterns can vary widely from daily foraging behaviours to broader migration or territorial movements. This challenge is of general interest because it impacts the ability to manage wildlife populations effectively. In this study, we conduct diffusion analysis based on European badger (Meles meles) movement data obtained from three different regions in the UK (Gloucestershire, Cornwall, and Northern Ireland) and fit a generalised linear mixed-effects model to examine the relationship between variables. We also feature a novel application of extended dynamic mode decomposition (EDMD) to uncover patterns relating to badger social organisation. By applying our approach to these different populations, we were able to assess its performance across a range of badger densities. A key result was that in some areas, EDMD clusters matched observed group home ranges, whilst in others, discrepancies likely arose because of population management interventions, such as badger culling. The methods presented offer a promising approach for studying territoriality and the impacts of management strategies on animal movement behaviour. Author summaryWild animals move for many reasons, such as searching for food, finding mates, or maintaining territories, and these movements can be affected by changes in their environment. In this comparative study, we focused on European badgers, a social species whose movements are important for understanding behaviour and disease spread. Using GPS data from different locations around the UK, we explore how badger movement patterns vary both from day to day and over longer periods, revealing differences by sex, season, and region. The core contribution of this study lies in the novel application of extended dynamic mode decomposition (EDMD) alongside a more established generalised linear mixed-effects model (GLMM), together capturing movement dynamics across multiple timescales. These tools offer a new way to interpret animal behaviour including territoriality, and can be adapted to other species and ecological contexts. While dependent on tracking data, this approach lays the groundwork for future tools that may inform wildlife management and policy in conservation and disease control.

ecology↗

Sherlock - A flexible, low-resource tool for processing camera-trapping images

1O_LIThe use of camera traps to study wildlife has increased markedly in the last two decades. Camera surveys typically produce large datasets which require processing to isolate images containing the species of interest. This is time consuming and costly, particularly if there are many empty images that can result from false triggers. Computer vision technology can assist with data processing, but existing artificial intelligence algorithms are limited by the requirement of a training dataset, which itself can be challenging to acquire. Furthermore, deep-learning methods often require powerful hardware and proficient coding skills. C_LIO_LIWe present Sherlock, a novel algorithm that can reduce the time required to process camera trap data by removing a large number of unwanted images. The code is adaptable, simple to use and requires minimal processing power. C_LIO_LIWe tested Sherlock on 240 596 camera trap images collected from 46 cameras placed in a range of habitats on farms in Cornwall, UK, and set the parameters to find European badgers (Meles meles). The algorithm correctly classified 91.9% of badger images and removed 49.3% of the unwanted empty images. When testing model parameters, we found that faster processing times were achieved by reducing both the number of sampled pixels and bouncing attempts (the number of paths explored to identify a disturbance), with minimal implications for model sensitivity and specificity. When Sherlock was tested on two sites which contained no livestock in their images, its performance greatly improved and it removed 92.3% of the empty images. C_LIO_LIThough further refinements may improve its performance, Sherlock is currently an accessible, simple and useful tool for processing camera trap data. C_LI

ecology↗