Tarantulas and other invertebrates kept as pets have welfare needs that are poorly understood, and uncertainty about their sentience requires a precautionary approach.
Tarantula and invertebrate pet welfare operates in conditions of genuine scientific uncertainty about the capacity of these animals to experience pain and suffering. While the evidence for insect sentience is contested, research suggests some invertebrates show avoidance learning and physiological responses to noxious stimuli that warrant a precautionary welfare approach. From a precautionary standpoint, ensuring tarantulas and other invertebrates are provided with appropriate temperature, humidity, substrate depth, and appropriate food avoids potential suffering even if the capacity to suffer remains uncertain. Molting in tarantulas is a critical period requiring appropriate conditions - insufficient humidity causes molting complications that can trap and kill the animal. Wild-caught tarantulas experience capture stress and face poor survival odds in captivity compared to captive-bred individuals.