In “The Oceans’ Shifting Balance” (editorial, Dec. 11), you rightly point out the serious consequence of excess carbon dioxide on shelled animals and hard corals. But dissolving shells and coral skeletons are only the outward face of ocean acidification.
Excess carbon dioxide also causes problems on the inside, affecting the internal chemistry of potentially all marine species, shelled or non.
Carbon dioxide easily slips through the skin of fish, squid and sea urchins, altering cell and body fluid chemistry the same way it alters seawater.
Animals can restore their pH balance, but it’s costly, leaving less energy for growing, reproducing and fighting disease. These changes are not yet fatal, but they may cause long-term population declines.
So, ocean acidification is about much more than disintegrating reefs; it’s about substantial losses from an already depleted ocean that one billion people (and counting) depend upon for their major source of protein.
Carl Safina, The New York Times. 16 December 2008. Article.