FRANCE - Anyone who has spent their summer in France in 2018 could attest to the increase in its temperature. The nation experienced its worst summer heat on record. While the kids enjoy the coolness of the lake, the shellfish producers could only watch from a distance as their mussels and oysters perished in the hands of what can be considered as sustained temperatures.
The ocean has always been a home to many species and their existence often result to a rather dynamic environment. Despite its ever changing conditions, the ocean remains to be a valuable part of nature as it houses the world's most exquisite of creatures. However, the human-induced effects of climate change and the increase in carbon emissions have made the ocean waters warmer. More than the increase in temperature, it is the diseases that has become widespread among marine animals that poses the new challenge among sea creatures.
Every aquaculturist knows that the temperature in the waters plays a huge role in the health and growth of aquatic species. What is certain is that higher temperatures require species for higher energy, which means higher demand for food. A malnourished fish makes them more susceptible to stress.
The study conducted by Dr. Tommy Leung, a parasitology expert from the University of England in Australia, has revealed in its study the relationship of the water temperatures to the severity and the duration of the outbreaks.
"If you live in a more temperate region, when you have a disease outbreak, almost half of your stock dies. If you live in a tropical country, there is a likelihood that more than 90% of your stocks will die," Leung explained. To add more to the problem, the disease outbreak in tropical regions almost usually experience in the outbreak in a much shorter time. "This fact practically means that you have less time to respond to any form of a potential outbreak."
With the rise in ocean temperatures, it has become possible for temperature regions to experience shorter outbreaks as well, leaving them with almost no room to react to it. However, the situations become more complex considering all the other factors present.
"There are various types of infectious agents, each one with their own parameters. For example, fungi thrive in a much lower temperature than viruses and bacteria, so the conditions that might make the fungi survive might be deadly to bacteria," Leung explained.
Temperature is not the only factor that can be considered a stressor by aquaculturists. Reduction in oxygen as well as lower pH levels can also cause stress on both the finfish and the shellfish. With the magnitude of how climate change makes the temperature rise up, aquaculturists are worried that it might put the species in ocean water suffer even more.
