Projected marine climate change: effects on copepod oxidative status and reproduction

Abstract

Zooplankton are an important link between primary producers and fish. Therefore, it is crucial to address their responses when predicting effects of climate change on pelagic ecosystems. For realistic community-level predictions, several biotic and abiotic climate-related variables should be examined in combination. We studied the combined effects of ocean acidification and global warming predicted for year 2100 with toxic cyanobacteria on the calanoid copepod, Acartia bifilosa. Acidification together with higher temperature reduced copepod antioxidant capacity. Higher temperature also decreased egg viability, nauplii development, and oxidative status. Exposure to cyanobacteria and its toxin had a negative effect on egg production but, a positive effect on oxidative status and egg viability, giving no net effects on viable egg production. Additionally, nauplii development was enhanced by the presence of cyanobacteria, which partially alleviated the otherwise negative effects of increased temperature and decreased pH on the copepod recruitment. The interactive effects of temperature, acidification, and cyanobacteria on copepods highlight the importance of testing combined effects of climate-related factors when predicting biological responses.

An updated synthesis of the observed and projected impacts of climate change on the chemical, physical and biological processes in the oceans

“…More recent work continues to strongly support the findings of AR5 that many species are undergoing geographical and phenological shifts as a result of warming (Vehmaa et al, 2013;Goberville et al, 2014;Kamya et al, 2014;Mackenzie et al, 2014a;Church et al, 2013;Mackenzie et al, 2014a,b,c;Queirós et al, 2014;Rice et al, 2014). The AR5 found that zooplankton have exhibited some of the most extreme geographic range shifts of over 100 km decade −1 .…”

“…Synergistic negative effects have been observed on the growth, survival, fitness, calcification and development of organisms (Padilla-Gamino et al, 2013;Vehmaa et al, 2013;Gaitán-Espitia et al, 2014;Gobler et al, 2014;Hyun et al, 2014;Mackenzie et al, 2014b;Madeira et al, 2014;Maugendre et al, 2014Roy et al, 2014;Schram et al, 2014;Rosa et al, 2014a,b;Schmidt et al, 2014a). In some cases, hypoxic conditions have been observed to mediate the negative effects of ocean acidification (Mukherjee et al, 2013).…”

“…Studies on non-calcifying zooplankton indicate a variety of sub-lethal effects under RCP8.5, including decreased egg production, lower hatch success and decreased survival of nauplii in copepods (Vehmaa et al, 2013;Zervoudaki et al, 2013;Pedersen et al, 2014). The AR5 has high confidence that embryos of Antarctic krill are vulnerable to increased seawater concentrations of CO 2 (Larsen et al, 2014) but Atlantic species have been found to be resilient (Sperfeld et al, 2014).…”

“…Recent work continues to highlight the effects of secondary drivers such as ocean acidification, hypoxia and food availability on the capacity of an organism to adapt to changing temperatures and increasing numbers of recent studies are highlighting the interactive effects of temperature and secondary drivers (Vehmaa et al, 2013;Ko et al, 2014;Mackenzie et al, 2014b,c;Madeira et al, 2014;Pope et al, 2014). A recent study has demonstrated that trans-generational plasticity can mediate the effects of warming in a fish species (Shama et al, 2014); however, there remains low confidence in our understanding of the potential evolutionary adaptation to warming.…”

Early Development of the Threespine Stickleback in Relation to Water pH

“…The current ocean acidification and change in the equilibrium of the seawater chemistry are so rapid that they will most likely lead to major changes in marine ecosystems and impact marine life (Pelejero et al, 2010). For more than a decade, the biological responses of phytoplankton (Lohbeck et al, 2012), foraminifera (Bijma et al, 2002), pteropods (Bednaršek et al, 2017), bivalves (Jansson et al, 2013), crustaceans (Vehmaa et al, 2013) and fish (reviewed by Clements and Hunt, 2015;Esbaugh, 2017) have been studied under different ocean acidification scenarios. Research suggests that mobile species, such as crustaceans and fish are less sensitive to acidification than sessile species, possibly due to their high metabolic rates and active regulation of internal pH (reviewed by Kroeker et al, 2013).…”