Fly the coop! Vertical structures influence the distribution and behaviour of laying hens in an outdoor range

BackgroundThe number of free-range farms has greatly increased in the Australian egg industry, up by 64% over the past 5 years and representing 34% of the retail egg sales last year. Nonetheless, free-range systems offer particular challenges to farmers. The use of the outdoor range is variable among hens; their distribution is usually not uniform across the range and they tend to stay close to features such as walls or fences, resulting in high stocking density in particular areas, with associated welfare and environmental concerns. MethodsUsing video recordings, we investigated the effect of erecting a series of vertical structures in the range on the hens' numbers, distribution and behaviour. ResultsHens were very attracted to the structures, which altered their distribution and behaviour. Up to 160 hens were seen around each structure, giving a density of 6.4 hens/m(2). The hens spent 40% of their time pecking at the structures and standing in these areas and less time walking, preening or ground pecking. ConclusionElucidating which physical features fulfil hens' biological needs could improve their use of outdoor ranges.