The Southern Ocean, which goes around the southern continent, will lose less than half of the krill population due to climate change caused by human activity.

What is happening in the Southern Ocean?

A study by the University of Colorado Boulder mentioned that the effects of climate change on krill, a crucial species in ecosystems, will have little difference from the natural decline of the population until the late 21st century, reported SciTech Daily.

According to a study published in Frontiers in Marine Science, that points to serious implications for the local food web and the Southern Ocean's population of fish. There is a $2 billion fish oil industry that gets fish oil from Omega-3 supplements in retail giants like Costco.

Zephyr Sylvester, lead author on the paper called krill "the link to that holds the ocean ecosystem." He emphasized that they are essential to sustain all the predators found in the Southern Ocean, as stated in  Eureka Alert.

Cassandra Brooks, a co-author on the paper and an assistant professor of environmental studies, stated that the changes should be separated from climatic influences that are natural and from man-made factors. To measure how much change is likely to occur from natural variability, and separately from climate change, allows everyone involved to plan better for the future and manage the krill for all animals depending on it.

Since these tiny Antarctic krill are not totally affected by climate change despite residing in one of the world's most vulnerable locations, it's critical to distinguish from trends caused by humans and that those that occur naturally in krill habitat during planning and mapping harvest limits.

Read also: French Government Will Build the Polar Pod for Studying the Antarctic Ocean for Long-Term Investigation

Sylvester's study used this kind of climate model to test how far can climate change exert dramatic changes on Antarctic marine ecosystems. 

Small creatures that hold the key to the ecosystem

Krill is about 2.5 inches in length. They form large colonies of zooplankton that appear like a living sludge on the ocean surface. It is the major food source for all animals in the Southern Ocean, which is crucial in the Antarctic waters. These include mammals like penguins, seals, fish, and whales that are now only recovering from previous hunting.

Despite having the most biomass of any species on earth, they can only survive in a specific and narrow temperature range. The variables in the underwater environment are a big factor to consider.

The Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR), an international body created as part of the Antarctic Treaty System, currently runs fishing in the Southern Ocean and all related activities.

A widespread international acknowledgment of the critical need to know the way things might be affected by climate change and getting the right data on how climate naturally varies is an important goal, remarked Sylvester, cited University of Colorado, Boulder.

Definition of Natural Variability

However, differentiating the effects of human-caused climate change from natural variations in a region is challenging to define. How researchers see the actual influences that have changed the Southern Ocean was done through models. One specific difference is factoring in how Antarctic krill are not affected by climate change that might be included in these complex models.

Related article: National Geographic Cartographers Add the Southern Ocean of Antarctica on The World Map as The Fifth Ocean