Within-Generation and Transgenerational Plasticity of a Temperate Salmonid in Response to Thermal Acclimation and Acute Temperature Stress

Abstract

Brook trout (Salvelinus fontinalis) exhibit within-generation and transgenerational plasticity for thermal performance, although neither response appears sufficient to cope with long-term climate change effects.

Transgenerational effects on body size and survival in Brook charr (Salvelinus fontinalis)

“…We also found that Fulton's index of second‐year fish in laboratory environment was influenced by the temperature treatment, with fish from cold‐acclimated parents having a lower index than those from warm‐origin adults. This result contrasts with those presented in Penney et al (2022), where Brook charr juveniles from cold‐acclimated parents had better body condition than those from warm‐acclimated parents. In this study, however, differences in temperature between cold and warm treatment were more important (10°C or 21°C, for cold and warm respectively), and were maintained for a longer period in separate treatments (from May until fall reproduction) than in our study.…”

“…Interestingly, sire identity explained a significant proportion of the variation in survival at that same period. Our findings are in line with those of Penney et al (2022) that revealed a greater contribution of sires, relative to dams, to transgenerational effects in Brook charr families produced from parents acclimated to cold and warm temperatures and kept in controlled conditions. Again, however, we recognize that low survival and a small number of families in the cold treatment may have hampered our results.…”

“…Yet, the importance of transgenerational effects in the wild is still debated, especially in cases when the environment is variable among generations (Sánchez‐Tójar et al, 2020; Uller et al, 2013; Yin et al, 2019). Moreover, paternal effects have been much less studied than maternal effects, despite their increasingly recognized importance (McAdam et al, 2014; Penney et al, 2022; Rutkowska et al, 2020). Transgenerational studies assessing the effect of temperature variation during maturation/reproduction of both males and females on their subsequent juvenile morphology and survival until maturation/reproduction in the wild are thus still needed (Donelson et al, 2018).…”

“…Moreover, paternal effects have been much less studied than maternal effects, despite their increasingly recognized importance (McAdam et al, 2014;Penney et al, 2022;Rutkowska et al, 2020).…”

“…Thermal tolerance is shown to vary among strains of Brook charr, with individuals from northern latitude having more limited thermal tolerance to warm conditions (Stitt et al, 2014). A recent study in controlled conditions, using Brook charr families produced by parents acclimated to cold or warm temperatures, showed limited response to warmer temperatures, but revealed that sires appeared to have greater contributions to transgenerational effects than dams (Penney et al, 2022). Another study found 188 differentially methylated regions in progenies issued from breeders exposed to different temperature conditions during the final steps of gonad maturation (Venney et al, 2022), which could possibly translate into different phenotypes and fitness for those fish.…”