Scientists and fishers alike are concerned about what the latest climate change models mean for the mussel fishery.
Sea temperatures could rise significantly in the future, including in the tropics, and rainfall is similarly expected to increase. As such, conditions may soon favor disease-causing bacteria and plankton species which produce toxins, including the lethal paralytic shellfish toxin (PST) that tends to target mussels and oysters. Researchers from Gothenburg University, Sweden working on the Mangalore coast in South-West India have been looking into just how the possible coming climate will challenge the Green Mussel industry in India and the results have left people like scientist Lucy Turner deeply troubled.
"If the changes in the environment put the mussels' bodies under higher stress levels than usual, and we then challenge them with these microorganisms, the immune system may become compromised," said Turner, who is the lead investigator for the research.
The combination of warmer temperatures and reduced salinity strongly affects the health of mussels, the researchers discovered after raising the mussels under high temperature/low salt conditions while also exposing them to toxic plankton and bacteria species. And that spells out murky water ahead for the rapidly growing shellfish industry, Turner explained: "The demand for marine products is growing at an unprecedented rate...there is also a drive to move from small scale fishing methods to larger scale commercial operations."
“We know that climate change is causing a change in the timing and duration of the monsoon which can significantly lower the seawater salinity...this is likely to increase the chance of outbreaks of toxic plankton blooms and make farming bivalves such as mussels increasingly challenging," Turner added.
Turner and the research crew are hopeful that the Indian government will take the study results and implement long-term monitoring programs as a means to stem the impending issue.
"The Indian government needs to be vigilant about monitoring coastal water quality, particularly as the shellfish industry continues to grow," said Turner.
As of now, scientists are working on similar projects observing clams and prawn farms and how they are affected in changing climates.