Little is known about how individual laying hens behave and use resources when housed in large groups in non-cage housing systems. As more hens in commercial settings are housed in large groups, and their welfare assessed accordingly, understanding individual hen behavior and resource use is paramount. Therefore, a wireless body mounted sensor system was developed to track the location of individual laying hens in a non-cage environment. The development of this new technology stimulated ethical discussion surrounding development of technology with regards to animal welfare assessment through a Philosophy of Technology lens. Yet, technology in agriculture is a double-edged sword, especially as regards animal welfare. Therefore, technology should be utilized when appropriate and relinquished when necessary. By acknowledging what is gained or lost (from farm to fork) with regards to animal welfare by utilizing a technological tool. Along this vein, the impact of using a hen-worn sensor system on hen resource use and agonistic behaviors was investigated. Harness presence had a minimal negative long-term effect on resource use and agonistic behavior, suggesting that hens were able to habituate to wearing the sensor. Following this work, two parsimonious sampling strategies were identified for monitoring the behavior of individually identifiable hens: continuous observation for 30 minutes every 1.5 hours and instantaneous scans every 15 minutes. Using this newly identified sampling strategy, individual hen behavior and sensor data were collected at 19, 28, 48, and 66 wk of age along with physical assessments as described in the Welfare Quality® Assessment Protocol for Poultry. Mean differences in the amount of time hens spent standing, sitting, and perching were observed, and differences in the variability of behavior performance were observed for many of the assessed behaviors. This highlights that even though group averages may not change, hens individually may be variable in their physical condition and behavioral repertoire. The most robust physical parameter to measure with regards to current, past and future behavioral profiles was claw length, and the optimal age for performing welfare assessment was 48 wk. Output from the hen-worn sensor system and video-based behavioral observations were collated in ArcMap 10.0, part of the Geographic Information System (GIS) software package. By combining the behavior and sensor data in GIS, a spatiotemporal representation of individual behavior was developed. For this study, data from 48 and 66 wk of age were used to characterize individual hen behavior through utilization distributions, hot spot mapping, and conspecific overlap calculations. The behaviors of feeding, foraging, and preening were specifically targeted to identify spatiotemporal patterns for a behavior that was constrained by the location of the resource (feeding), an appetitive behavior that was not constrained by a location for its performance (foraging), and a grooming and social behavior that could indicate a hen's affective state (preening). These results provide new insight into individual hen behavior in a non-cage system and present a platform for a new type of agricultural research, which integrates wildlife tracking techniques, to understand the individual experience in large group. This information may be able to provide insight into hen preference and can be utilized when developing best practices or designing new housing environments.
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