Global Wild Mammal Biomass and Animal Welfare Scale

Scientific estimates of wild mammal biomass reveal the enormous scale of animal populations experiencing welfare conditions, providing important context for understanding the potential scale of welfare improvements in wild animal populations.

Key Facts

Wild mammals represent approximately 4% of total mammal biomass on Earth, compared to 60% livestock and 36% humans
An estimated one trillion fish live in the world's oceans, each potentially experiencing welfare-relevant states
The number of wild birds is estimated at approximately 300 billion globally
Scale arguments suggest that wild animal welfare interventions, if effective, could affect far more individuals than all farm animal welfare interventions combined
The vast majority of wild animals die as juveniles through predation, disease, and starvation

Welfare Considerations

Understanding the scale of wild animal populations provides important context for animal welfare priorities. If wild animals experience significant welfare-relevant states, the potential scale of suffering in nature vastly exceeds that in human-managed systems. This scale argument suggests that wild animal welfare research and practical interventions, though in their infancy, could potentially affect more individual animals than any other welfare domain. The uncertainty about wild animal sentience and the practical challenges of intervention do not negate the importance of taking the scale question seriously in welfare priority-setting.

What You Can Do

Engage with welfare biology research and literature to understand the scale of wild animal welfare
Support organizations like the Welfare Biology Network studying practical wild animal welfare interventions
Consider wild animal welfare in your overall approach to animal advocacy and prioritization
Share the scale perspective with other animal advocates to broaden welfare discussions
Support research into wild animal welfare that informs practical intervention design