Effects of Acidification on Crustaceans
Crustaceans play an important role in the ecology and economy of the Mid-Atlantic region. Certain crustacean species, such as the blue crab, are essential (keystone) species which also serve as a link between the ocean floor (benthic) and the open ocean (pelagic) environment. Crustacean species also support productive fisheries in the region, making them not only ecologically important, but critical to the economy of the Mid-Atlantic. However, a limited number of studies have been conducted to quantify the response of crustaceans to acidification, and those studies have demonstrated variable responses in growth and survival under acidified conditions.
Similar to mollusks and some zooplankton, such as krill, younger life stages of crustaceans tend to be more sensitive to acidification compared to juveniles and adults. Larval blue crab have exhibited lower survival and smaller size at reduced pH. Conversely, researchers quantified the growth and food consumption of juvenile blue crab exposed to increased temperature and acidity in a laboratory experiment and found there was no significant effect of increased acidity on crab growth rate or food consumption. Furthermore, the crustacean cuticle, a structure important for protection and mating in many species, and has been the focus of two studies on the effects of climate change on crustaceans in the Mid-Atlantic. Researchers have observed an increase in the calcification rate of adult blue crabs exposed to high acidity in a laboratory setting. Similarly, increased acidity caused an increase in the amount of calcium carbonate (in the form of high-magnesium calcite) in juvenile blue crabs.
Therefore, while older life stages of crustaceans may be more resilient to ocean acidification, the higher vulnerability of younger life stages needs to be taken into account in order to understand how populations of crustacean species will be impacted in future conditions. More studies on additional species at different life stages are necessary to fully understand the response of crustaceans to future climate stressors.
References
Coffey, WD, Nardone, JA, Yarram, A, Long, WC, Swiney, KM, Foy, RJ, Dickinson, GH. 2017. Ocean acidification leads to altered micromechanical properties of the mineralized cuticle in juvenile red and blue king crabs. Journal of Experimental Marine Biology and Ecology 495, 1-12.
Glandon, HL, Kilbourne, KH, Schijf, J, Miller, TJ. submitted. Counteractive effects of increased temperature and pCO2 on the carapace thickness and chemistry of juvenile blue crab, Callinectes sapidus, from the Patuxent River, Chesapeake Bay. Journal of Experimental Marine Biology and Ecology.
Glandon, HL, Miller, TJ. 2017. No effect of high pCO2 on juvenile blue crab, Callinectes sapidus, growth and consumption despite positive responses to concurrent warming. ICES Journal of Marine Science: Journal du Conseil 74, 1201-1209.
Glitz, SM, Taylor, CM. 2017. Reduced growth and survival in the larval blue crab Callinectes sapidus under predicted ocean acidification. Journal of Shellfish Research 36, 481-485.
Kroeker, KJ, Kordas, RL, Crim, R, Hendriks, IE, Ramajo, L, Singh, GS, Duarte, CM, Gattuso, JP. 2013. Impacts of ocean acidification on marine organisms: quantifying sensitivities and interaction with warming. Global change biology 19, 1884-1896.
Ries, JB, Cohen, AL, McCorkle, DC. 2009. Marine calcifiers exhibit mixed responses to CO2-induced ocean acidification. Geology 37, 1131-1134.