# Monitoring Night-Time Activity Patterns of Laying Hens in Response to Poultry Red Mite Infestations Using Night-Vision Cameras

## TL;DR

Poultry red mites disrupt hens' nighttime sleep, causing increased activity and stress, which can be monitored using night-vision cameras to improve pest management.

## Contribution

A novel automated video analysis method to monitor the impact of poultry red mites on hens' night-time behavior at both group and individual levels.

## Key findings

- Group activity nearly doubled after mite infestation and remained high throughout the night.
- Individual hens spent significantly more time in active states after infestation, with a 23-fold increase in PRM-related behaviors.
- Mite-induced disruptions were most severe from two hours after lights-off to two hours before lights-on.

## Abstract

The poultry red mite feeds on the blood of hens at night, leading to disrupted sleep, reduced welfare, and lower productivity. Effectively managing mite infestations requires regular monitoring and the ability to adapt control strategies to farm conditions. This study investigated how the presence of mites alters hens’ night-time behaviour. Using night-vision cameras and an automated video analysis method, we quantified night-time activity patterns at both the group and individual level before and after mite introduction. Before infestation, hens displayed expected resting behaviour, with group activity declining after lights-off and remaining low until a brief anticipatory spike before lights-on. After infestation, group activity nearly doubled and remained high throughout the night, with no activity peak before lights-on. The most pronounced disruption occurred from two hours after lights-off to two hours before lights-on. At the individual level, time spent in the most active state increased from 43 min before infestation to 120 min after infestation. The increase in activity was supported by a nearly 23-fold rise in annotated behaviours linked to PRM, such as head shaking and head scratching. These findings suggest that poultry red mites disrupt the normal sleep pattern of laying hens and may induce chronic stress. Understanding the timing and extent of this disruption supports the use of continuous, automated behavioural monitoring in integrated pest management strategies in commercial egg production.

The poultry red mite (PRM) feeds on hens’ blood at night, disrupting sleep, harming welfare, and reducing productivity. Effective control may lie in dynamic Integrated Pest Management (IPM), which relies on routine monitoring and adaptation to farm conditions. This study investigated how PRM infestations affect the night-time activity of hens. Three groups of eight hens, housed in enriched cages, were monitored with night-vision cameras over a two-month period, both before and after artificial PRM introduction, while PRM levels were simultaneously recorded. To quantify changes in behaviour, we developed an activity-monitoring algorithm that extracts both group-level and individual night-time activity patterns from video recordings. Group activity between 18:00 and 03:00 was analyzed hourly, and individual activity between 21:00 and 00:00 was classified into four activity categories. Before infestation, group activity declined after 19:00, remained low from 20:00 to 01:00, and peaked just before the end of the dark period. After infestation, activity remained elevated with no anticipatory activity peak towards the end of the dark period. Individual data showed an increase in time spent in the most active activity category from 24% to 67% after infestation. The rise in calculated activity was supported by a nearly 23-fold increase in annotated PRM-related behaviours, specifically head shaking and head scratching. These findings suggest that PRM mostly disrupted sleep from two hours after lights-off to two hours before lights-on and may have acted as a chronic stressor. Automated video-based monitoring could strengthen dynamic IPM in commercial systems.