A recent publication in the prestigious scientific journal Science of the Total Enviroment realized the possibility that the chorito (Mytilus chilensis), of great commercial importance for the country, has the physiological capacity to adapt to possible scenarios of temperature increase on the white continent.
The scientific work was led by Jorge Navarro, researcher at the Center for Dynamic Research of High Latitude Marine Ecosystems (IDEAL) and academic at the Institute of Marine and Limnological Sciences of the Austral University of Chile (UACh).
In recent years, the scientist has focused his interest on the climate crisis and its effects on marine organisms of ecological and economic importance, which inhabit the south-austral area of Chile and Antarctica.
To carry out the study, an experiment was carried out for 80 days. The objective was to know how this bivalve that lives in the Magallanes Region behaves, is exposed to low temperatures during winter and whose production in Chile exceeds 400 thousand tons per year and places the country as the second world producer of this resource. The scientific team set out to know how this species, upon arriving in Antarctica, could face certain thermal conditions, both current and those of future climate change scenarios.
The Magallanes mussels were exposed to four temperature conditions.
“The first was a control condition, in which they were at 8° Celsius, which is the temperature at which they were collected. The second, an Antarctic summer condition, which corresponds to 2° C. Then, an Antarctic winter condition of -1.5° C. And a fourth treatment consisted of exposing them to an Antarctic affected by climate change, equivalent to 4 ° C”, explains the researcher.
The mussel mortality was very low in all experimental conditions, with values of 2 to 3% in the group exposed to Antarctic winter conditions (-1.5 °C) and in the control group (8 °C).
“Winter temperature continues to be a barrier for potential invaders, but if climate change continues and the temperature increases according to the predictions that have been made, it is most likely that the mussel could establish itself in Antarctica,” he explains. the researcher at the IDEAL Center and dean of the Faculty of Sciences of the UACh, Leyla Cárdenas, co-author of the study.
The scientific work also considered the feeding and growth activity of the mussels.
“We detected that there was a clear decrease in the ingestion rate in the animals exposed to the lowest temperature of -1.5° C. Although they did not die, they ate little and when doing a bioenergetic analysis, we found that there was negative growth (low of body weight). However, at the other three experimental temperatures an increase in the ingestion rate was observed, with different degrees of growth, explains Navarro.
“While it is true, this species has its ingestion and growth rates affected under Antarctic winter conditions, which suggests that it would not have enough energy to survive for a year on this continent. That could explain why this species is not found in Antarctica permanently. Although it does not die, it does not have the capacity to grow and therefore would not have the capacity to reproduce, he adds.
Potentially invasive species
Mussels are found on all continents except Antarctica. The mussel is one of the most relevant mollusks for aquaculture in Chile and, in parallel, it is characterized by having a wide tolerance to various environmental factors, such as temperatures, salinity and oxygen.
In ecological terms, it is considered a “bioengineered species” because it lives in banks or mantles and generates suitable substrates for other organisms such as algae, microalgae and invertebrates.
In recent years, international Antarctic studies have placed mussels as the first potentially invasive species in Antarctica.
Following the results of the research, Navarro assures that “if the increase in temperatures occurs in the Antarctic Peninsula due to climate change, the mussels would be exposed to 3 or 4 degrees more. This would be a favorable condition for them to be able to feed, grow and possibly reproduce in environments such as the Western Antarctic Peninsula, all helped by the increase in maritime transport activity through the Southern Ocean.
The study can be read HERE.