Recent developments in parrot cognition: a quadrennial update

The evolution of social play in songbirds, parrots and cockatoos - emotional or highly complex cognitive behaviour or both?

Social play has been described in many animals. However, much of this social behaviour among birds, particularly in adults, is still relatively unexplored in terms of the environmental, psychological, and social dynamics of play. This paper provides an overview of what we know about adult social play in birds and addresses areas in which subtleties and distinctions, such as in play initiation and social organisation and its relationship to expressions of play, are considered in detail. The paper considers emotional, social, innovative, and cognitive aspects of play, then the environmental conditions and affiliative bonds, suggesting a surprisingly complex framework of criteria awaiting further research. Adult social play has so far been studied in only a small number of avian species, exclusively in those with a particularly large brain relative to body size without necessarily addressing brain functions and lateralization. When lateralization of brain function is considered, it can further illuminate a possibly significant relevance of play behaviour to the evolution of cognition, to management of emotions, and the development of sociality.

Innovative problem solving by wild falcons

Innovation (i.e., a new solution to a familiar problem, or applying an existing behavior to a novel problem1,2) plays a fundamental role in species' ecology and evolution. It can be a useful measure for cross-group comparisons of behavioral and cognitive flexibility and a proxy for general intelligence.3,4,5 Among birds, experimental studies of innovation (and cognition more generally) are largely from captive corvids and parrots,6,7,8,9,10,11,12 though we lack serious models for avian technical intelligence outside these taxa. Striated caracaras (Phalcoboenus australis) are Falconiformes, sister clade to parrots and passerines,13,14,15 and those endemic to the Falkland Islands (Malvinas) show curiosity and neophilia similar to notoriously neophilic kea parrots16,17 and face similar socio-ecological pressures to corvids and parrots.18,19 We tested wild striated caracaras as a new avian model for technical cognition and innovation using a field-applicable 8-task comparative paradigm (adapted from Rössler et al.20 and Auersperg et al.21). The setup allowed us to assess behavior, rate, and flexibility of problem solving over repeated exposure in a natural setting. Like other generalist species with low neophobia,21,22 we predicted caracaras to demonstrate a haptic approach to solving tasks, flexibly switching to new, unsolved problems and improving their performance over time. Striated caracaras performed comparably to tool-using parrots,20 nearly reaching ceiling levels of innovation in few trials, repeatedly and flexibly solving tasks, and rapidly learning. We attribute our findings to the birds' ecology, including geographic restriction, resource unpredictability, and opportunistic generalism,23,24,25 and encourage future work investigating their cognitive abilities in the wild. VIDEO ABSTRACT.

The Gordon Memorial Lecture: Laying Hen Welfare

Preference tests remain a useful tool in the assessment of laying hen welfare and have been used to establish what types of resources and enrichments are most likely to meet the birds' needs. Evidence on the underlying structure of bird preference suggests that hens make stable and reliable choices across time and context. This means that their preferences can also be used as a benchmark in the validation of other welfare indicators. Hens have sophisticated cognitive abilities. They are quick to form associations between events and they are flexible in how they apply their knowledge in different contexts. However, they may not form expectations about the world in the same way as some mammalian species. Limited research in this area to date seems to show that hens judge situations in absolute terms rather than evaluating how a situation may be improving or deteriorating. The proportion of hens housed in cage-free systems is increasing globally, providing birds with greater behavioural freedom. Many of the problems associated with cage-free systems, such as keel bone fractures, mortality and injurious pecking, are slowly reducing due to improved experience and appropriate changes in rearing practices, diet, housing design and alignment of breeding goals. However, much remains to be done. The design and performance of veranda-based systems which provide hens with fresh air and natural light is a promising avenue for future research aimed at optimising hen welfare and improving sustainability.