All organisms carry out metabolic processes to produce chemical energy, but these biochemical pathways are not perfectly efficient and energetic waste is lost as heat. The interplay of heat production/retention/loss in endotherms has been well studied via thermal imaging. However, there is a striking absence of literature on the thermal output of ectotherms, especially invertebrate animals. We have developed a new thermal imaging technique to investigate waste heat production in the nematode worm C. elegans. No direct measurement of this metabolic waste heat has been made in C. elegans or any other mesoinvertebrate using IR imaging techniques.