Oceanographer Vanesa Romero Kutzner, from the EOMAR Group of ECOAQUA, led an investigation exposing the jellyfish species Aurelia aurita to extreme temperatures and concluded that they not only manage to adapt, but also increase their reproduction.
Jellyfish, which belong to the phylum Cnidaria are organisms with a great capacity for adaptation to environmental variability. These animals, among the oldest on the planet, demonstrate great stability in facing adverse external factors such as starvation, hypoxic conditions, and ocean acidification, which seems to have contributed to their survival over about 600 million years.
Aurelia aurita ephyra. Author: Nathan Hubot
The doctoral thesis of the researcher Vanesa Romero Kutzner from the EOMAR, 'The respiratory metabolism of marine plankton: A time-course study in bacteria and medusa', was published by the University Institute for Research in Sustainable Aquaculture and Marine Ecosystems (ECOAQUA), and provides further evidence of environmental adaptation by studying the metabolic response of Aurelia aurita (also called the common jellyfish), when artificially exposed to marine heatwaves, which are linked to climate change.
Known consequences of marine heatwaves are loss of marine biodiversity. However, the results of Romero's research indicate that Aurelia aurita polyps are not only able to survive but also to increase their reproduction strategies. In addition, these polyps can recover their metabolic rates when returning to their normal temperature after being exposed to the anomalously high temperatures simulated for the study.
Other results of this research showed that, under starvation conditions, more respiratory CO2 is produced than oxygen consumed. This finding has been fundamental in the conclusions since it is commonly assumed that the relationship between the concentration of respiratory CO2 and O2 is direct. Thus, the variability in this relationship must be taken into account when calculating, for example, carbon fluxes in the ocean.
Vanesa Romero Kutzner on board of the British oceanographic vessel James Cook, taking water samples to analyse CO2 concentrations on the transatlantic route Miami-Tenerife.
This is the first study of its kind to be carried out during the metamorphosis of jellyfish and its impact is relevant insofar as its results can have a direct effect on the economy of coastal areas if there is an increase in A. aurita populations. Jellyfish blooms are known to impact adversely a variety of industries, including tourism and aquaculture. The results of this thesis might help to assess the economic impacts, for example, tourists might not choose to return to a destination affected by jellyfish.
Jellyfish can be found in every ocean in the world. There are more than 2,000 known species of jellyfish. It is a simple organism, with practically no organs (more than 95% is water). Thanks to its adaptability and its strategic life cycle, which covers different ecological niches, it can be expected that these species might proliferate under future anthropogenic ocean scenarios, and even return to their role as a monopolistic predators.
Strobila: Polyps are sessile and through the strobila life stage (picture) they can produce planktonic ephyra. Author: Nathan Hubot
Vanesa Romero Kutzner's thesis has been directed by two professors of the ULPGC, May Gómez and Ted Packard. Both, the author of the thesis (which obtained a Cum Laude qualification) and the directors, belong to the Research Group on Ecophysiology of Marine Organisms (EOMAR) of the University Institute ECOAQUA. The development of this thesis has been possible thanks to the ACIISI pre-doctoral contract scholarship and the European Social Fund.
During her early career, Romero received recognition from La Caixa for her outstanding academic record in the degree of Marine Sciences. She has also been a speaker at numerous international conferences, such as the Ocean Science Meeting (Portland-USA), and the Jellyfish Bloom International Symposium (Ciudad del Cabo-South Africa).
The new doctor from the ULPGC has carried out numerous research stays, at the Institute of Marine Sciences (Barcelona-Spain), ICBM (Wilhemshaven-Germany), Oxford Brookes University (Oxford-UK), at the National Oceanography Center (Southampton-UK), and has participated in a transatlantic campaign from Miami to Tenerife on board of the British oceanographic vessel James Cook.
Doctoral thesis defense act.
For more information, contact: Beatriz Díaz beatriz@mandarinacomunicacion.es / 620410871