Growth performance and survival of larval Atlantic herring, under the combined effects of elevated temperatures and CO2

Abstract

In the coming decades, environmental change like warming and acidification will affect life in the ocean. While data on single stressor effects on fish are accumulating rapidly, we still know relatively little about interactive effects of multiple drivers. Of particular concern in this context are the early life stages of fish, for which direct effects of increased CO2 on growth and development have been observed. Whether these effects are further modified by elevated temperature was investigated here for the larvae of Atlantic herring (Clupea harengus), a commercially important fish species. Over a period of 32 days, larval survival, growth in size and weight, and instantaneous growth rate were assessed in a crossed experimental design of two temperatures (10°C and 12°C) with two CO2 levels (400 μatm and 900 μatm CO2) at food levels mimicking natural levels using natural prey. Elevated temperature alone led to increased swimming activity, as well as decreased survival and instantaneous growth rate (Gi). The comparatively high sensitivity to elevated temperature in this study may have been influenced by low food levels offered to the larvae. Larval size, Gi and swimming activity were not affected by CO2, indicating tolerance of this species to projected "end of the century" CO2 levels. A synergistic effect of elevated temperature and CO2 was found for larval weight, where no effect of elevated CO2 concentrations was detected in the 12°C treatment, but a negative CO2 effect was found in the 10°C treatment. Contrasting CO2 effects were found for survival between the two temperatures. Under ambient CO2 conditions survival was increased at 12°C compared to 10°C. In general, CO2 effects were minor and considered negligible compared to the effect of temperature under these mimicked natural food conditions. These findings emphasize the need to include biotic factors such as energy supply via prey availability in future studies on interactive effects of multiple stressors.

Elevated Temperature Does Not Substantially Modify the Interactive Effects Between Elevated CO2 and Diel CO2 Cycles on the Survival, Growth and Behavior of a Coral Reef Fish

“…For example, temperatures above the natural preference range were shown to enhance growth of larval yellowtail kingfish, Seriola lalandi (Watson et al, 2018). In contrast, elevated temperature negatively impacted the growth and survival of larval Atlantic herring, Clupea harengus, despite the elevated temperature still being within the species preferred thermal range (Sswat et al, 2018). Differences between studies could potentially be linked to food availability, with studies reporting positive effects usually providing a continuous supply of high-density food that enabled energetic demands to be met.…”

“…For example, the positive effects of elevated temperature on growth of larval flat fish, Solea senegalensis, were reduced when CO 2 was also elevated (Pimentel et al, 2014). Furthermore, while elevated temperature was shown to reduce growth and survival in larval Atlantic herring, Clupea harengus, the effects of elevated CO 2 were shown to be temperature dependent (Sswat et al, 2018; see also Gobler et al, 2018). From a behavioral perspective, elevated CO 2 and temperature interacted synergistically on predation rate, but antagonistically on predator selectivity of the dottyback, Pseudochromis fuscus (Ferrari et al, 2015).…”

Divergent responses of Atlantic cod to ocean acidification and food limitation

“…For other species, a decrease in growth rate under elevated CO 2 was observed, for example in the inland silverside (Menidia beryllina; Baumann, Talmage, & Gobler, 2012), for yellowfin tuna (Thunnus albacares; Bromhead et al, 2015), and Atlantic herring (Clupea harengus; Frommel et al, 2014). However, another study found no effect on Atlantic herring (Sswat, Stiasny, Jutfelt, Riebesell, & Clemmesen, 2018). Still others showed an increase in growth rate, for example in orange clown fish (Amphiprion percula; Munday, Donelson, Dixson, & Endo, 2009), in cod (Frommel et al, 2012) in summer flounder (Paralichthys dentatus; Chambers et al, 2013, Chambers et al, 2014 and in sand smelt larvae (Atherina presbyter; Silva et al, 2016) under elevated pCO 2 levels.…”

Global environmental changes negatively impact temperate seagrass ecosystems

“…Here, it appears that OA may be the dominant stress factor. It is likely that underlying mechanisms of stress resilience can facilitate habituation of fish, and explain unaffected growth and survival of fish larvae, under the pressure of OA (Sswat et al 2018).…”