There's this fast-swimming zooplankton (a small organism) that lives in groups. And it is tiny, growing to about 6 cm. But lying at the base of the food web in the Southern Ocean, the krill is what links the ecosystem together. Its population is on the decline, and this can have an unimaginable impact on marine life in the long run. How?
A new study published recently says krill population in its Antarctic habitat is likely to decline about 30% this century due to both natural climate variability and human activity-induced climate change. The study also adds that it will be difficult to "tell the difference between natural and human-caused effects on krill until late in the 21st century". This is worrisome due to two reasons. One is that unless we know how exactly human activity affects krill population, it may be difficult to initiate relevant steps to improve the situation. Two, it is said that "natural climate variability can obscure human-driven trends". Neither augurs well for the krill population.
As mentioned, krill are tiny creatures. But they are one of the most abundant too. For several sea creatures including penguins, seals, fish, and whales - in the ocean surrounding Antarctica, krill are the main food. Not just that. Many sea animals feed on the creatures that consume krill, which is why the krill has an important role to play in the aquatic food chain, especially in the Southern Ocean. If the krill population keeps coming down, it could affect several other creatures, causing a severe imbalance in the food chain. Krill are adapted to surviving harsh winters. But one wonders how well they can adapt to climate change.
Did you know?
The largest animal on Earth, the blue whale feeds almost exclusively on krill. Apparently, it needs to eat a few tonnes of these tiny crustaceans every day!
Picture Credit : Google