The research indicates that the Antarctic urchin Sterechinus neumayeri could be more vulnerable to the ocean warming scenario predicted for the end of the century.

With the objective of understanding the impacts that the increase in temperature in oceans can generate in the face of future climate change scenarios in key species for ecosystems, in this case the sea urchins Pseudechinus magellanicus for the Magellan area and Sterechinus neumayeri for Antarctica, a team of researchers carried out a study that was recently published in the Journal of Thermal Biology.

The Center for Dynamic Research in High Latitude Marine Ecosystems (IDEAL) of the Austral University of Chile (UACh), the Institute of Marine and Limnological Sciences (ICML), the Calfuco Coastal Laboratory (LCC), the Department of Biology and the Quebec-Ocean Institute of the Université Laval in Canada and of the Station Biologique de Roscoff, belonging to the Sorbonne Université, participated in the publication.

The group of scientists made a comparison between laboratory measurements with others carried out directly on the ground that allowed detecting differences between these two conditions, which makes it necessary to consider the complexity of marine environments for future predictions of climate change.

Jorge Navarro, a researcher at the IDEAL Center and an ICML academic, explained that sea urchins are considered bioengineers and key links within marine ecosystems, so the effect that climate change may have on them will also impact other organisms in the marine communities, both algae and animals.

“To escape a predator and desiccation, sea urchins rely heavily on their ability to quickly regain orientation after experiencing an inverted position. This behavior means that they are considered model species to evaluate their performance under adverse environmental conditions, and that in this study was measured as sensitivity and thermal stress,” he assured.

Camille Détrée, the researcher who led the investigation, added that in the case of sub-Antarctic and Antarctic sea urchins, very few studies have investigated their ability to maintain essential functions over a range of temperatures, which is paramount to assessing the future of these species in a context of climate change.

“In response to ocean warming, the ‘climate envelopes’ of many marine organisms, i.e. the range of conditions in which populations or species currently persist, have changed: They have shrunk, expanded, or moved to higher latitudes. In addition, increasing human activity is weakening the physical barrier, for example, the circumpolar current that keeps Antarctica isolated from the rest of the world, making it easier for non-native species to enter. Thus, studying the thermal range of Antarctic and sub-Antarctic urchins makes it possible to predict the future of these populations in a context of climate change”.

The IDEAL Center researcher, Ignacio Garrido, stated that “urchins are organisms that are present in most marine food webs, from tropical, temperate and polar environments. Their physiological response to the accelerated global warming we are witnessing today provides us with important clues as to how organisms and benthic communities will respond to these changes.”

Risks to marine ecosystems

Regarding the relevance of this type of study, Ignacio Garrido points out that “experimentally recreating conditions that are predicted in 50 or 100 more years helps us to determine if aquatic organisms will be able to survive or not. The consequences of their not surviving could generate important impacts at the population and ecosystem level, due to the functional and ecological role that each organism fulfills in ecosystems.”

“Sea urchins that cannot adapt to temperature conditions or other environmental factors due to future climate could see their biological fitness affected, with negative consequences for the ecosystem, due to their role as bioengineers in algae forests,” reinforced Jorge Navarro.

However, the researchers stress that experimental bias must be taken into account in predicting the functioning of marine organisms in a changing environment. In turn, it cannot be assumed that the vulnerability to climate change of a species will be the same throughout its area of distribution, since each population is adapted to local conditions and not all of them will respond in a similar way to climate change.

To read the study, click here.