Traffic mortality is the leading cause of premature death in outdoor cats in many countries, and the welfare case for traffic risk mitigation must be balanced against the behavioral benefits of outdoor access.
The welfare calculus of cat outdoor access is genuinely complex because outdoor cats enjoy richer behavioral lives while facing substantially higher mortality risk. Indoor-only cats live longer on average but may experience reduced behavioral welfare if their environments are inadequately enriched. The key welfare question is not indoor versus outdoor but whether the outdoor environment is safe enough to justify the risk and whether the indoor environment is enriched enough to meet behavioral needs. In high-traffic urban areas, the mortality risk of outdoor access often outweighs the behavioral benefit, especially when indoor enrichment can substantially substitute for outdoor complexity.