Impacts of paternal transmission of PCBs and global warming on the evolution of pace-of-life syndrome (POLS) during the early life stages of a cold stenothermic fish (Arctic charr).

In the context of strong historical and climate anthropological pressure, we studied the impact of paternal transmission of PCBs on offspring of the stenothermic salmonid, Artic charr. Indeed, the transgenerational effects of maternal transmission are widely studied, unlike the paternal effect, which is often limited to epigenetic impacts. The study aims to test the effects of temperature and PCBs on the Artic charr (Salvelinus alpinus), whose population within the perialpine lakes has remained low for about a decade. A previous study (Realis-Doyelle et al., 2023) on the effect of maternal transmission of PCB, coupled with an increase in temperature, showed a collapse in offspring survival as well as morpho-anatomic disorders in Salvelinus alpinus. This study follows on from the previous one, we contaminated 21 males with intra-peritoneal PCB injection at three levels of concentration one month before spawning. Each male fertilised a pool of 12 female oocytes not contaminated with PCBs. Each fertilized pond was separated in two and incubated at 4.5°C and 8.5°C, respectively. To explore the effects, we have relied on the POLS theories that suggest a co-variation of traits of life. The results show no population collapse (∼50 % survival), in contrast to the maternal contamination study (∼12 % survival). We may issue the hypothesis that this smaller importance of paternal transmission is due to the synergic impact of PCB and temperature on fewer parameters, in particular for survival than female transmission.