Context:Antarctic krill (Euphausia suberba) fishing is banned in U.S. waters due to concerns that exploitation of Antarctic Krill could impact whales, seals and other animals that feed on the shrimp-like creatures. Krill fishing has been taking place for decades in Antarctica, where krill are most abundant.
About Antarctic Krill
Antarctic Krill are shrimp like crustaceans living the Southern Ocean.
It’s estimated that there are over 700 trillion adult individuals of Antarctic Krill.
Adult krill can live anywhere in the Southern Ocean – from the very surface layer to the seafloor, and from inshore areas to the deep open ocean.
Antarctic krill grow up to 6cm in length and can weigh 1 gram.
Antarctic krill (and other krill species) are bioluminescent, meaning they produce light. They are frequently found in such abundance that they colour the sea a reddish-brown. They may be small individually, but there is an estimated 400 million tonnes of Antarctic krill in the Southern Ocean.
Antarctic krill aggregate in schools or swarms, where the density of the animal can be as high as 30,000 individuals per cubic metre.
Antarctic krill are a key species, supporting populations of penguins, seals, whales and other marine life.
Antarctic krill feed on phytoplankton (single celled marine plants), which absorb carbon dioxide. Krill then egests this carbon through their faecal pellets and by shedding their exoskeletons, which then both sink to the sea floor where some of the carbon gets stored away.
It is one of the most common species in its range and it is not at risk of endangerment or extinction.
IUCN Status: Least Concern
Related
Previous year questions 2014
Which one of the following is the correct sequence of a food chain?
A Diatoms—Crustaceans—Herrings
B Crustaceans—Diatoms—Herrings
C Diatoms—Herrings—Crustaceans
D Crustaceans—Herrings—Diatoms
Answer is A
Diatoms are genera of Algae-Primary producers.
Crustacean, any member of the subphylum Crustacea (phylum Arthropoda), a group of invertebrate animals consisting of some 45,000 species distributed worldwide. Crabs, lobsters, shrimps, and wood lice are among the best-known crustaceans- Primary consumers.
Herring are forage fish, mostly belonging to the family of Clupeidae-Secondary consumers.
Practice questions
With reference to Antarctic Krill, consider the following statement:
It is primary producers in marine food chain.
It helps in sequestering carbon thereby curbing climate change.
Statement 1 is incorrect-It is primary consumers feed on phytoplankton.
Statement 2 is correct- Antarctic krill feed on phytoplankton (single celled marine plants), which absorb carbon dioxide. Krill then egests this carbon through their faecal pellets and by shedding their exoskeletons, which then both sink to the sea floor where some of the carbon gets stored away.
Statement 3 is incorrect- It is one of the most common species in its range and it is not at risk of endangerment or extinction.it has a least concern status by IUCN. However, they are facing challenges from anthropogenic activities like Krill fishing and Climate Change.
