Résumé
Following a heated local controversy about the construction of waste incinerator in the Fos-sur-Mer industrial area near Marseille, Rresidents pointed at the lack of knowledge about the industry’s cumulative impacts on their health and environment. Under pressure and confronted to an anarchic use of scientific contradictory claims,, some of their elected representatives requested a territorial check-up. They also supported the creation of a citizen-based organization (IECP or Ecocitizen institute for knowing pollution) whose aim is it to develop independent but situated scientific research on the chronic effects of pollution, but also to lobby the administration so it may change its regulatory monitoring practices. The objective of this paper is to examine the work accomplished by the IECP so that “undone science” (Frickel at al. 2010) about pollution and its impacts on living organisms gets done by taking care of the specificity of the territory. (and is made locally relevant to the Fos-sur-Mer specific situation). Special attention will be paid to a participative biomonitoring experiment aiming at documenting and mapping pollution in the Gulf of Lion as scientists working for the IECP accepted to switch from a standard sentinel species (comber or Serranus cabrilla) to another species (conger or Conger conger), to meet anglers’ advice and requests. We will tell the many stories which were shared with us about how congers qualified to become the adequate “diplomatic fish” for monitoring pollution with, both for scientists and anglers, after a moment of great tension. Elaborating on actor-network theory (Callon 1986; Latour 2001) and multi-species ethnographies (Kirksey 2014), we will go on discussing their competencies and achievements as newly appointed sentinel species, which helped sensing mercury and PCB contamination hotspots. We will conclude on the place of non-humans as spokesbeings in negotiated protocols for environmental monitoring.