Response of lobster larvae to ocean acidification and warming (NOAA’s Ocean Acidification Program and Sea Grant)
The input of anthropogenic carbon into the atmosphere has caused large scale ocean warming and acidification (OA) that has important implications for commercial fisheries in the Northeastern United States (Caldeira & Wickett, 2005, Gledhill et al., 2015). The Northwest Atlantic is experiencing more rapid increases in temperature and acidification than other parts of the world (Fabry et al., 2009). The Gulf of Maine (GOM), in particular, is warming faster than 99.9% of the world ocean with its warmest year on record in 2012 (Mills et al., 2013, Pershing et al. 2015). Consequently, over recent decades the fishing industry has witnessed traditional commercial fish populations receding from the south and expanding to the north (Pinsky et al., 2013, Nye et al., 2009). While most of these shifts have been attributed to ocean warming, the impact of acidification has only been examined in a few species (Green et al., 2013, Gledhill et al., 2015), and the interactive effects of warming and acidification remain poorly understood. In the present study we focus on the interactive effects of ocean warming and acidification on the iconic American lobster (Homarus americanus), one of New England’s most valuable fisheries.
A recent literature review conducted as part of the Northeast Coastal Acidification Network (NECAN) revealed how little is known about the consequences of ocean acidification for marine fisheries in our region (Gledhill et al., 2015). The section on marine crustaceans in that review, co-authored by two of our research team, cited 24 studies conducted on the effects of acidification on crustaceans currently found in the Northwest Atlantic, only two of which have been published on the American lobster (Keppel et al., 2012, Ries et al., 2009). No studies have comprehensively assessed the impact of ocean warming and acidification on physiological performance or gene expression. Nor has any study addressed how lobster subpopulations differ in their response to these climate stressors along the environmental gradients occurring over the species’ geographic range, despite evidence of local population differentiation (Beneston et al., 2014). This study is designed to increase our understanding of the response of the lobster’s most vulnerable early life stages to warming and acidification across New England’s steep north-south thermal gradient.