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A Northern Atlantic Krill Species Demonstrates Tolerance to Ocean Acidification

Paper Reviewed
Opstad, I., Mangor-Jensen, A., Sperfeld, E., Johansen, I.S., Fransson, A., Chierici, M. and Dalpadado, P. 2018. Effects of high pCO2 on the northern krill Thysanoessa inermis in relation to carbonate chemistry of its collection area, Rijpfjorden. Marine Biology 165: 116, https:doi.org/10.1007/s00227-018-3370-7.

Marine organisms inhabiting the polar regions of the world's oceans are expected to be among the first casualties of ocean acidification, as future seawater pH declines in these regions are predicted to be among the largest to occur.

Krill (euphausiids) play an important role in the food web of many high-latitude ecosystems by transferring energy from phytoplankton to higher trophic-level species. Thus, they are an important focal group in ocean acidification (OA) studies, yet little is known regarding the possible impacts of OA on Thysanoessa inermis, one of the most abundant krill species to inhabit the northern waters of the Atlantic Ocean.

Hoping to provide some critical information in this regard, Opstad et al. (2018) conducted an 11-week laboratory experiment in which they subjected individuals of Thysanoessa inermis to current (450 µatm) and high (1500 µatm) pCO2 seawater values, analyzing several characteristics pertaining to their growth and survival under such conditions. In describing their findings, the authors report "no significant effects of high pCO2 on survival, growth, moulting, oxygen consumption and feeding rate were observed," which observations, in the words of the seven researchers, indicate that "T. inermis is tolerant to predicted high OA levels."

Posted 22 August 2018