Exploring local adaptation and the ocean acidification seascape – studies in the California Current Large Marine Ecosystem

Abstract

Abstract. The California Current Large Marine Ecosystem (CCLME), a temperate marine region dominated by episodic upwelling, is predicted to experience rapid environmental change in the future due to ocean acidification. The aragonite saturation state within the California Current System is predicted to decrease in the future with near-permanent undersaturation conditions expected by the year 2050. Thus, the CCLME is a critical region to study due to the rapid rate of environmental change that resident organisms will experience and because of the economic and societal value of this coastal region. Recent efforts by a research consortium -the Ocean Margin Ecosystems Group for Acidification Studies (OMEGAS) -has begun to characterize a portion of the CCLME; both describing the spatial mosaic of pH in coastal waters and examining the responses of key calcification-dependent benthic marine organisms to natural variation in pH and to changes in carbonate chemistry that are expected in the coming decades. In this review, we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast. Highlighted in this contribution are (1) the OMEGAS sensor network that spans the west coast of the US from central Oregon to southern California, (2) initial findings of the carbonate chemistry amongst the OMEGAS study sites, and (3) an overview of the biological data that describes the acclimatization and the adaptation capacity of key benthic marine invertebrates within the CCLME.

You Better Repeat It: Complex CO2 × Temperature Effects in Atlantic Silverside Offspring Revealed by Serial Experimentation

“…Rearing-containers were filled with clean seawater (filtered to 1 µm and UV sterilized). Optimal salinity (27)(28)(29)(30)(31) and light conditions (15 h light:9 h dark) for rearing M. menidia were maintained across experiments [60]. The number of CO 2 × temperature treatments and replicates varied between experiments (see Table 1).…”

Sensitivity of sea urchin fertilization to pH varies across a natural pH mosaic

“…Locally, ocean pH variability regimes arise due to geographic differences in oceanographic and biological features. Variation in these can create natural hot spots of (Hofmann et al., ), or refuges from (Kapsenberg & Hofmann, ), harmful low pH exposures (e.g., pH T < 7.7). The potential selection pressure that pH variability envelopes impose is not well studied or understood.…”

Lipid consumption in coral larvae differs among sites: a consideration of environmental history in a global ocean change scenario

“…Adaptation to local regimes of pH and temperature occurs over a sufficient spatial scale where environmental conditions differ consistently and where gene flow is low [18][19][20], and in this context, local adaptation to temperature has been well studied [21,22]. Studies in other systems provide evidence that local adaptation to pH regimes can occur in nature [23][24][25]. If coral populations are locally adapted to their environmental regime, corals living in a naturally more acidic environment may have developed physiological tools for maintaining normal function in low-pH seawater, as has been shown for elevated temperature [26].…”