No maternal or direct effects of ocean acidification on egg hatching in the Arctic copepod Calanus glacialis

PLoS One. 2018 Feb 7;13(2):e0192496. doi: 10.1371/journal.pone.0192496. eCollection 2018.

Abstract

Widespread ocean acidification (OA) is transforming the chemistry of the global ocean and the Arctic is recognised as the region where this transformation will occur at the fastest rate. Moreover, many Arctic species are considered less capable of tolerating OA due to their lower capacity for acid-base regulation. This inability may put severe restraints on many fundamental functions, such as growth and reproductive investments, which ultimately may result in reduced fitness. However, maternal effects may alleviate severe effects on the offspring rendering them more tolerant to OA. In a highly replicated experiment we studied maternal and direct effects of OA predicted for the Arctic shelf seas on egg hatching time and success in the keystone copepod species Calanus glacialis. We incubated females at present day conditions (pHT 8.0) and year 2100 extreme conditions (pHT 7.5) during oogenesis and subsequently reciprocally transplanted laid eggs between these two conditions. Statistical tests showed no effects of maternal or direct exposure to OA at this level. We hypothesise that C. glacialis may be physiologically adapted to egg production at low pH since oogenesis can also take place at conditions of potentially low haemolymph pH of the mother during hibernation in the deep.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acids / chemistry*
  • Animals
  • Arctic Regions
  • Copepoda / physiology*
  • Eggs*
  • Female
  • Oceans and Seas*

Substances

  • Acids

Grants and funding

The study was financially supported by a grant from the FRAM High North Research Centre for Climate and the Environment through the Ocean Acidification and Ecosystem Effects in Northern Waters Flagship to PT. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.