AUG 01, 2021 8:03 AM PDT

Shrinking Krill Population Threatens Antarctic Ecosystem

WRITTEN BY: Annie Lennon

Large-scale climate patterns have a direct impact on the reproductive success of female Antarctic krill, which in turn has a negative effect on the Antarctic ecosystem. The study was published in Marine Ecology Progress Series by researchers from Oregon State University.

Antarctic krill are a type of zooplankton that live between five and seven years and grow to little more than two inches in length. They are considered a 'keystone species' as they form the main diet for marine predators in the Antarctic region, including penguins, seals, whales, and fish. They are also used as feed for fish farms and as a source of omega-3 oil for supplements. 

The western Antarctic peninsula is a popular fishing spot, one of the biggest areas for krill spawning. It is also the fastest-warming area of Antarctica and has seen krill numbers decline in recent years. Understanding the factors that affect population patterns of Antarctic krill, say the researchers, is important for predicting future demographic fluctuations. 

For the study, the researchers examined krill population data from 1993 to 2008. In doing so, they found that the healthier female krill of reproductive age were during spawning season, the more juvenile krill there would be in following years. They also found that fluctuations in large-scale climate patterns and seasonal variations in climate were the most significant predictors of female health during the spawning season. 

The Western Antarctic Peninsula's climate patterns are regulated by the Southern Annual Mode (SAM) and the Multivariate El Nino Southern Oscillation Index (MEI). Fluctuations in these patterns affect the availability of food sources for Antarctic krill. 

The climate data examined by the researchers showed that SAM has been trending positively in recent years, meaning it has been warmer and more intense. This positive phase is predicted to continue under climate change, and continue to have a negative effect on female krill during spawning season. 

"It is really critical to start including climate change impacts as part of the plan," said Kim Bernard, one of the authors of the study "Antarctic krill are a super unique and fascinating species. So many predators feed on them. If you have a collapse of the krill population, you would be putting all of those populations at risk."

The researchers highlighted that Adelie penguins rely on mature, female krill as a food source due to their high lipid content. In particular, they can help penguin chicks survive the winter. The researchers noted that a decline in krill populations is linked to reduced numbers of Adelie penguins in the Northern parts of the Antarctic Peninsula. 

 

Sources: Marine Ecology Progress SeriesCCAMLRScience Daily

About the Author
University College London
Annie Lennon is a writer whose work also appears in Medical News Today, Psych Central, Psychology Today, and other outlets. When she's not writing, she is COO of Xeurix, an HR startup that assesses jobfit from gamified workplace simulations.
You May Also Like
AUG 12, 2022
Earth & The Environment
Humans, not climate, contributed to mammal community similarities 10,000+ years ago
AUG 12, 2022
Humans, not climate, contributed to mammal community similarities 10,000+ years ago
In a recent study published in Nature Communications, an international team of researchers discuss how the increasing ho ...
AUG 22, 2022
Earth & The Environment
Modern Heat Waves Feel Worse Than Heat Index Suggests
AUG 22, 2022
Modern Heat Waves Feel Worse Than Heat Index Suggests
In a recent study published in Environmental Research Letters, a pair of researchers at the University of California at ...
AUG 25, 2022
Drug Discovery & Development
Seasonal Flu Could Get Knockout Punch from Antiviral Drugs and Antibody Therapy Combo
AUG 25, 2022
Seasonal Flu Could Get Knockout Punch from Antiviral Drugs and Antibody Therapy Combo
In a recent study published in Cell Reports Medicine, a team of researchers from McMaster University in Ontario, Canada ...
SEP 16, 2022
Genetics & Genomics
Grad Student Highlights: Shannon Barry (Florida Institute of Technology)
SEP 16, 2022
Grad Student Highlights: Shannon Barry (Florida Institute of Technology)
This interview series is focused on the graduate student experience across all STEM fields that allows them to get their ...
SEP 21, 2022
Neuroscience
What We Can Learn From Brain Asymmetry
SEP 21, 2022
What We Can Learn From Brain Asymmetry
A study published in eLife examined the subtle differences in functional organization between the left and right side of ...
SEP 30, 2022
Health & Medicine
Glyphosate, Now Found in Humans, Can Cause Convulsions in Animals
SEP 30, 2022
Glyphosate, Now Found in Humans, Can Cause Convulsions in Animals
Glyphosate is the chemical in a product called Roundup that kills weeds, especially grasses and broadleaf weeds that com ...
Loading Comments...