Leading birds by their beaks : the response of flocks to external perturbations

Peer reviewed

Guardian dogs protect sheep by guarding sheep, not by establishing territories and excluding predators

Guardian animals have been a common non-lethal method for reducing predator impacts on livestock for centuries in Europe. But elsewhere, livestock producers sometimes doubt whether such methods work or are compatible with modern livestock husbandry practices in extensive grazing systems. In this study we evaluate the hypothesis that guardian dogs primarily ‘work’ by establishing and defending territories from which canid predators are excluded. Eight maremmas and six free-ranging wild dogs of different sexes were fitted with GPS collars and monitored for 7 months on a large sheep property in north Queensland, Australia. Wild dog incursions into the territories of adjacent wild dogs and maremmas were recorded. Wild dog territories never overlapped and their home ranges infrequently overlapped. In contrast, 713 hourly locations from 120 wild dog incursions into maremma territories were recorded, mostly from three wild dogs. These three wild dogs spent a mean of 2.5–5.9 h inside maremma territories during incursions. At this location, maremmas worked by guarding sheep and prohibiting fine-scale interaction between wild dogs and sheep, not by establishing a territory respected by wild dogs. We conclude that shepherding behaviour and boisterous vocalisations of guardian dogs combined with the flocking behaviour of sheep circumvents attacks on sheep but does not prevent nor discourage wild dogs from foraging in close proximity. Certain husbandry practices and the behaviour of sheep at parturition may incur greater predation risk.

Double blind test series

Braille is a communication tool in decline, in America by 80% since 1950, and in the UK to the extent that only 1% of blind people are now thought to read Braille.1, 2 There are a variety of causal factors, including the phasing out of Braille instruction due to the educational mainstreaming of blind children and the resistance to learning Braille by those who lose sight later in life.3Braille is a writing system of raised dots that allows blind people to read and write tactilely. Each Braille character comprises a cell of six potentially raised dots, two dots across and three dots down. It is designed only to communicate the message and does not convey the tonality provided by visual fonts.However, in his book Design Meets Disability, Graham Pullin, observes that: “Braille is interesting and beautiful, as abstract visual and tactile decoration, intriguing and indecipherable to the nonreader ” and continues; “…braille could be decorative for sighted people.”4I assert that the increasing abandonment of Braille frees it from its restrictive constraints, opening it to exploration and experimentation, and that this may result in Braille becoming dynamic expression for the sighted, as well as the partially sighted and blind.Printmaking is well suited for this exploration. Printmaking processes and techniques can result in prints aesthetically compelling to both senses of sight and touch. Established approaches, such as flocking, varnishes, puff-ink, embossing and die cut, combined with experiments in new techniques in laser cutting and 3D printing, create visually and texturally vibrant prints.In this paper I will detail my systematic investigation of sensually expressive printmaking concentrating on the issues surrounding Braille as a printmaking design element paying particular attention to the approaches and techniques used not only in producing its visual style but to those techniques used to keep it integrally tactile.