Arctic Tipping Points

While the team of IMEDEA (Spain) is investigating the effect of ocean acidification and warming on larval stages of bivalves, Norwegian ATP members look into processes even earlier into the life cycle of benthic bivalves: fertilisation.

It is hypothesized that early life-stages of benthic invertebrates, particularly those species building calcareous shells, may be particularly sensitive to ocean acidification, perhaps in combination with increased temperature. Motility of sperm can be one factor explaining reduced fertilisation success. Thus, motility will be measured under different experimental treatments using a microscope video camera (see the video), and speed of swimming sperm cells will be calculated using CellTrak 1.3 program. The proportions of moving and immobile sperm cells can also be determined from videos. This gives us an indication of sperm condition, which can then be related to fertilization rates.