Mantis shrimps have remarkable sensory abilities and complex behaviours suggesting sophisticated neural processing. Their welfare raises important questions about how far our moral concern for invertebrates should extend.
Mantis shrimps occupy an intellectually interesting position in the animal welfare landscape: they possess sensory and neural capabilities that in other animals would immediately trigger welfare consideration, yet as marine invertebrates they are routinely caught, transported, and killed with no welfare scrutiny. The precautionary logic that applies to fish welfare applies here too: where there is credible evidence of nociception and potentially of pain experience, the burden of proof should not fall entirely on the animal. Mantis shrimps show avoidance learning, make complex decisions about territory defence, and invest significantly in home construction — behaviours that suggest a level of environmental awareness that complicates a simple dismissal of their moral status. As the science of invertebrate sentience advances, our welfare frameworks will need to engage more seriously with where the boundaries of moral consideration lie, with mantis shrimps representing a compelling edge case.