Can we achieve positive welfare through enrichment? A focus on fishes

Abstract

The recognition of their emotional lives, cognitive abilities, and a certain form of consciousness in animals under human care has profoundly changed the way their well-being is considered. While it is essential to provide living conditions that meet their behavioural needs, it is equally important to offer stimuli that allow the animal to actively interact with its environment in order to develop its adaptive capacities, particularly through environmental enrichment. Due to the much later recognition of fish as sentient beings compared to terrestrial vertebrates, current knowledge on ways to improve their well-being through environmental enrichment remains fragmented. This issue is becoming a major societal concern due to the growing interest of society and various sectors in fish welfare. This non-exhaustive review aims to present recent research avenues concerning fish under human care, whether for commercial, recreational, conservation, or experimental purposes. After defining what is meant by enrichment, we will discuss the physical, sensory, social, and cognitive enrichment strategies currently being explored, before addressing the limitations of their implementation as well as future perspectives. Fish represent a far greater number of species than terrestrial vertebrates. We will see that while some enrichment strategies show promising potential, much knowledge still needs to be acquired to develop relevant strategies adapted to each species and life stage.