If we could know how the body temperature of an oyster can vary in situ according to its way of life, then we could better understand how to improve its survival to the infection in the environment, in order to better manage the oyster crisis. In this Labex Emergence project, our objective is to measure how the C. gigas oyster's endogenous temperature varies in situ depending on whether it is high on the lower or upper foreshore, as a function of the weather, exondation, and the seasons. We seek to find out when and how the body temperature of the oyster could rise to induce a thermal response to increase its survival to the OsHV-1 viral disease (Delisle et al., 2018). For this purpose, we seek to develop a BODY (body temperature) body temperature sensor to know the amplitude and the variations of body temperature experienced by the oyster in situ according to its way of life. This sensor would be innovative because miniaturized and marinized. This would be the first endogenous sensor developed for an environmental sentinel intertidal species. We will have access for the first time to an endogenous biological data, at the scale of the animal, with a high frequency measurement.