This time of year, the cold-water coral Lophelia pertusa spawns in the NE Atlantic. At Tjärnö Marine Laboratory in Sweden, corals from reefs in Skagerrak are maintained and studied with focus on reproduction and larval ecology. In the laboratory, the corals spawn periodically from mid-January to the end of February, usually a few polyps at a time. An unusually massive spawning occurred last week when many male and female polyps released sperm and egg during a couple of hours resulting in tens of thousands of embryos – you can see these as the particles in the water in the video below. A probable cause of the massive spawning event could be build-up of chemical signals in the confined space of the aquarium.
In iAtlantic, embryos and larvae are studied in the context of climate change, to better understand how species survival and reproduction might be affected by changing conditions such as rising temperatures, and changes to seawater acidity, oxygen levels and ocean circulation patterns. So far, the studies have concentrated on the effects of temperature on embryo and larval development.
In the ongoing project, LIFE LOPHELIA, the attachment of larvae and choice of substrate is studied. Current research also includes studies on the effects of gamete (reproductive cells such as eggs or sperm) dispersal on fertilization rate and ability of larvae to swim in turbulence.
Video courtesy Ann Larsson, University of Goteborg.