Inconsistency between the environments of indoor pullet rearing and adult outdoor housing may increase the fearfulness in free-range hens. Rearing enrichments and/or range use may reduce adult fearfulness. Hy-Line Brown® chicks (n = 1700) were reared inside across 16 weeks with three enrichment treatments: weekly changing novel objects, custom-designed perching/navigation structures, or no additional enrichments. Pullets were transferred to a free-range system at 16 weeks of age, with range access provided from 25 weeks. At 62 weeks, 135 hens were selected from the three rearing treatments and two ranging groups (indoor: no ranging and outdoor: daily ranging) based on individual radio-frequency identification tracking. Individual behavioural tests of tonic immobility, emergence, open field, and novel object (pen level) were carried out on hens. Spectrograms of vocalisations were analysed for the open field test, as well as computer vision tracking of hen locomotion. The results showed few effects of rearing treatments, with outdoor rangers less fearful than indoor hens. The latency to step in the open field test negatively correlated with hen feather coverage. These results show that individual variation in ranging behaviours is present even following rearing enrichment treatments, and subsequent range use might be an indicator of bird fearfulness.

Artificial animal models (often called "dummies" or "decoys") are widely used in field and laboratory studies as a substitute for live animals or taxidermic mounts. This practice has been employed for at least 70 years (Tinbergen & Perdeck, 1951), but in the last two decades has begun to incorporate 3D-printing to generate models. Models are advantageous as they have fewer ethical concerns than live animals, and mitigate any risk of damage to taxidermy specimens that would otherwise be deployed in experiments. Broadly, 3D-printing creates custom models through computer-controlled layering of material, based on digital designs (Gross et al., 2014). Other reviews have already addressed the developing role of 3D printing in the ecological sciences (Behm et al., 2018;Walker & Humphries, 2019), but to date, there are few recommendations for a simple, repeatable process that can generate shape and color-accurate models. We seek to rectify this, so that researchers using artificial stimuli can create highly detailed models in an easy and replicable manner.

Daryl McPhee, Environmental History and Ecology of Moreton Bay, Melbourne: CSIRO Publishing, 2017, 208 pp., ISBN 9 7814 8630 7210, A$69.95