Defining _Welfare_ for Fish (Fish Welfare Initiative)

This report does not contain an executive summary. Here is a summary of the key points:

• This report from the Fish Welfare Initiative (FWI) outlines its working definition of welfare for farmed fish, which guides its operations.
• It begins by reviewing three traditional, broad categories of animal welfare definitions:
  • Feeling-based: Focuses on the animal's emotional states.
  • Function-based: Focuses on the animal's health and ability to adapt.
  • Nature-based: Focuses on the animal's ability to express natural behaviors.
• The report notes that these broad definitions are often impractical for on-farm management, as guaranteeing a complete absence of disease or providing a fully natural environment is not feasible.
• It introduces the "Five Freedoms" model as a more practical framework for defining welfare, which includes freedom from hunger, environmental challenges, pain, fear, and the freedom to express normal behavior.
• A key critique of the Five Freedoms is its grounding in "homeostatic principles," which incorrectly assumes that reducing all stress is always beneficial for an animal's welfare.
• The report argues that fish require biologically relevant challenges to experience optimal welfare and that low stimulation (hypostimulation) can lead to boredom and be detrimental.
• FWI's definition of welfare is therefore based on the concept of allostasis: the process of achieving stability through adaptation to a dynamic environment.
• According to allostatic theory, the relationship between stress and welfare is a bell curve:
  • Too little stress (hypostimulation) and too much stress (allostatic overload) lead to poor welfare.
  • An optimal, intermediate range of stress (eustress) improves welfare by allowing the animal to successfully cope, learn, and experience positive rewards.
• FWI defines a positive welfare state as one where an individual has the freedom to adequately (i.e., adaptively) react to challenges such as hunger, thirst, environmental changes, pain, and fear.
• This approach modifies the Five Freedoms model by focusing on achieving an allostatic equilibrium rather than simply eliminating stressors.
• FWI's definition is "feelings-based" as it centers on the fish's subjective perception of its ability to cope with its environment.
• Ultimately, the report concludes by endorsing the definition that "Animal welfare is the quality of life as perceived by the animal itself," aiming to provide fish with conditions for stimulation without overload, thus giving them a life worth living.