23 Apr Key differences discovered in the adaptation of plover seeds to climate change
A recent study has revealed that mussels, the second most cultivated aquaculture species in Chile, depending on the environmental conditions from which it originates, would have different adaptive capacities in the face of extreme events produced by climate change. Through a detailed analysis of oceanographic conditions and the physiology of mussels in different seedbeds in the Los Lagos region, the study identified differences in the response of mussel seeds with respect to their places of origin, which could be determinant for the sustainability of aquaculture in a scenario of climate change.
The latest report of the World Meteorological Organization 2024 has shocked by its conclusions on the state of the global climate: 2024 was probably the first year with a temperature more than 1.5 °C higher than the pre-industrial era, in addition to a rise in sea level and warming of the oceans that will be irreversible for hundreds of years.
These impacts, in addition to having consequences for the lives of millions of people, also have implications for the natural populations of marine organisms and those that grow in near-shore farming systems.
Faced with this scenario, an interdisciplinary team of researchers from the Millennium Institute in Coastal Socio-Ecology (SECOS), and institutions such as the Universidad de Concepción, Universidad Austral, Universidad Adolfo Ibañez among others, published in the journal Science of The Total Environment the results of a study developed by PhD student Nicole Castillo and the guidance of researcher Cristian Vargas, both from SECOS and the Laboratory of Coastal Ecosystems and Global Environmental Change ECCALab of the Universidad de Concepción.
The study analyzed samples of mussels from three contrasting geographical areas in the localities of Metri, Puelo and Caleta El Manzano (Hualaihué) in the Los Lagos Region. To understand the natural environmental conditions to which these populations are exposed, oceanographic data on temperature, salinity and pH were collected using buoys and sensors near the culture centers. This information allowed the design of controlled experiments in the laboratories of ECCALab and the Dichato Coastal Marine Biology Station of the University of Concepción, where the organisms were subjected to different environmental change scenarios.
Thus, the research represented a significant technical and logistical challenge, since we worked with more than 900 individuals whose feeding rates were measured, involving three natural populations and the interaction of these three environmental variables. Thus, this integrated approach not only allowed us to evaluate how environmental variability influences the adaptability of plover seeds to changes in environmental conditions (known as ‘phenotypic plasticity’), but also highlighted the importance of the human and technical effort required to carry out studies of this complexity.
“The results of this study indicate that the ability of plover (Mytilus chilensis) seeds to respond to environmental changes is influenced by the environmental variability regime, and how ‘predictable’ the fluctuations in these variables are,” explains Nicole Castillo, also a SECOS postdoctoral researcher. She adds that “in addition, in the lab we saw that plover seeds respond differently depending on where they come from, even if those places are very close. This suggests that the conditions of the environment where they grow influence their tolerance and resistance to extreme events”.
A model for aquaculture adaptation to climate change
One of the main findings of the study is that the adaptive capacity of plover seeds depends not only on their genetic variability, but also on the environment in which they grow. Populations exposed to greater environmental variability showed greater tolerance to extreme conditions, suggesting that certain environments may favor the resilience of marine organisms to climate change.
“These findings can contribute to the identification of farming areas that are more (or less) resilient to different stressors, providing key information to improve the ability of the farming industry to anticipate, respond and recover from environmental changes. In this sense, the results can be useful for decision making in management and planning, facilitating the development of strategies based on environmental variability and physiology” comments Cristian Vargas.
For Camila Barría, in charge of R+D+i of the Technological Institute of Mytiliculture, “the results of this research are part of the main challenge of the industry, since due to the high dependence on the environment (seeds and food), the main challenge for Chilean mytiliculture is to know the factors that determine the supply of seeds from the natural environment, since this is the key input that sustains the industry. This is why, from AmiChile and INTEMIT, we value this type of advances as they allow us to know the changes in the adaptation of our species and to project the industry in the context of climate change”.
Finally, Vargas delves into the usefulness of this type of methodology. “To understand how populations of farmed organisms might respond to climate change, at SECOS we have adopted a comprehensive approach. We monitor the ocean with lower-cost loggers and sensors, which allows us to characterize environmental conditions over time in the habitats of farmed species, such as mussels in this case, or also oysters. We then conduct experiments in the laboratory to assess how populations respond to the natural variability they face and to more extreme events, such as heat waves or episodes of low pH or low salinity. Finally, we complement these studies with genetic analyses to understand their local adaptation mechanisms or their sensitivity to these conditions.”