Ocean acidification, arguably climate change’s worst product where CO2 which has been released into the atmosphere is then absorbed by the ocean effectively lowering its pH level, is yet again being proven to negatively affect marine life. This time, a few researchers at the Tjärnö Marine Research Station in Sweden conducted a year and a half long experiment on ocean acidification’s affect on a marine invertebrate known as Balanus improvisus, a type of barnacle known to be sensitive to short term changes in ocean pH levels. The study took reared laboratory bread barnacles as well as field collected assemblages, and held some of each under normal ocean pH levels of 8.1 and a more acidic level of 7.5. Their results, were sadly quite predictable.
The acidification not only caused the barnacles mortality rate to heavily increase, but also led to reduced growth and reproduction rates. In fact, barnacles were even paired up with one another so as to increase breeding rates, yet still both the laboratory made and field collected samples held in the more acidic water, failed to produce any fertilized embryos. Though most of the surviving barnacles of the acidic water developed mature gonads ( organs used for reproduction) in the end they all failed to reproduce over the 16 months studied, meaning they were able to acclimate to their new environment, but only partially.
The two big aspects to take away here are firstly, that barnacles are ecologically important, economically important, and widely studied ecosystem engineers that if lost would be awful for marine environments and future studies on the health of environments. Secondly, that this study proves once again that climate change, specifically ocean acidification is detrimental to marine life across all aspects. So much aquatic life is quickly disappearing due to this phenomenon as well as ocean temperature risings, both of which are direct products of global warming. Sadly, these invertebrate are just another example, in a sea of them (pun not intended), of the major issues that are headed our way if we don’t reduce our carbon emissions.
Source
Anil A. C., 2018. Long term exposure to acidification disrupts reproduction in a marine invertebrate. PLoS One V. 13(2): 19-36.
Yet another marine organism at risk due to ocean acidification. You mention the ecological and economic advantages of barnacles, the article would have had even more impact if some of those were included. They would make interesting points.