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Antarctic KrillEuphausia superba

Every figure, record and mechanism on the Antarctic Krill profile was written from a source, and this is the working table behind it: 51 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Australian Antarctic Program, Australian Antarctic Division

Antarctic krill. Australian Antarctic Program, Australian Antarctic Division.

The page saysA crustacean about 6 centimeters long, so abundant it can turn the sea reddish-brown, that most larger Antarctic animals depend on, directly or indirectly.
The source saysAdult Antarctic krill are approximately 6 cm in length ... They are frequently found in such abundance that they colour the sea a reddish-brown. ... Most of the larger Antarctic animals (seals, whales, seabirds, fish and squid) depend on Antarctic krill, directly or indirectly.Note: "about" keeps "approximately"; "so abundant it can turn" for "frequently found in such abundance that they colour"
The page saysSouthern Ocean south of the Antarctic Convergence
The source saysAntarctic krill is one of 5 species of krill that lives in the Southern Ocean, south of the Antarctic convergence.
The page saysMainly phytoplankton; in winter, algae growing under the pack ice, seafloor detritus and other animals
The source saysThe primary food of krill is phytoplankton ... In winter, krill have to use other food sources such as algae growing on the underside of the pack ice, detritus on the sea-floor or the other animals in the water.
The page saysAn estimated 400 million tonnes in the Southern Ocean
The source saysthere is an estimated 400 million tonnes of Antarctic krill in the Southern Ocean
The page saysthe ability to shrink, burning its own body protein as fuel, when food is scarce in winter
The source saysthey must survive the winter months when food is scarce. ... They use this ability to continue growing and reducing their body size to help them survive. 'Downsizing' enables Antarctic krill to use their own body proteins as a source of fuel.
The page saysThe Antarctic krill (Euphausia superba) is one of the most abundant animal species on the planet.
The source saysAntarctic krill is one of the most abundant and successful animal species on the planet.
The page saysIt lives in the Antarctic waters of the Southern Ocean.
The source saysAntarctic krill is one of 5 species of krill that lives in the Southern Ocean ... There are 5 species of krill found in Antarctic waters.
The page saysAn adult is about 6 centimeters long and weighs more than a gram.
The source saysAdult Antarctic krill are approximately 6 cm in length and weigh over one gram.Note: AAD (current page) over ADW's older 5-6.5 cm and 2 g average
The page saysScientists estimate it lives for 5 to 10 years.
The source saysIt is estimated that Antarctic krill live for 5 to 10 years
The page saysKrill gather in schools or swarms, which can hold as many as 30,000 animals in one cubic meter of water.
The source saysAntarctic krill aggregate in schools or swarms, where the density of the animal can be as high as 30,000 individuals per cubic metre.
The page saysThey are often so abundant that they color the sea reddish-brown.
The source saysThey are frequently found in such abundance that they colour the sea a reddish-brown.Note: "so abundant that" for "such abundance that"; "often" for "frequently"
The page saysScientists estimate there are 400 million tonnes of Antarctic krill in the Southern Ocean.
The source saysthere is an estimated 400 million tonnes of Antarctic krill in the Southern Ocean
The page saysIn winter, krill turn to other food: algae growing on the underside of the pack ice, detritus (bits of dead matter) on the seafloor, or other animals in the water.
The source saysIn winter, krill have to use other food sources such as algae growing on the underside of the pack ice, detritus on the sea-floor or the other animals in the water.Note: "bits of dead matter" defines detritus; it is not a claim about krill
The page saysFood is scarce then, and lab studies show Antarctic krill can survive more than 200 days of starvation.
The source saysthey must survive the winter months when food is scarce. ... Laboratory studies have shown that Antarctic krill can survive more than 200 days of starvation.
The page saysThey shrink as they starve.
The source saysThey shrink in length as they starve.
The page saysKrill can molt (shed their hard outer shell) all their lives, and they use it to shrink as well as grow.
The source saysCrustaceans usually grow by moulting their hard shell (exoskeleton) ... Krill retain the ability to moult for life. They use this ability to continue growing and reducing their body size to help them survive.Note: "all their lives" for "for life"
The page saysThis "downsizing" lets them burn their own body proteins as fuel.
The source says'Downsizing' enables Antarctic krill to use their own body proteins as a source of fuel.Note: "lets" for "enables"
The page saysAt the end of summer, adults start to lose their sexual features.
The source saysAt the end of summer, adult krill begin to lose their sexual characteristics.
The page saysAfter a series of molts they look like two-year-old juveniles again, and in spring they mature once more.
The source saysAfter a series of moults they again resemble two-year-old juveniles ... In spring, adults once more begin to develop sexual characteristics and become mature before the spawning season.
The page saysMost of the larger Antarctic animals (seals, whales, seabirds, fish and squid) depend on Antarctic krill, directly or indirectly.
The source saysMost of the larger Antarctic animals (seals, whales, seabirds, fish and squid) depend on Antarctic krill, directly or indirectly.
The page saysThere is an estimated 400 million tonnes of Antarctic krill in the Southern Ocean.
The source saysthere is an estimated 400 million tonnes of Antarctic krill in the Southern Ocean
The page saysTheir swarms can hold as many as 30,000 animals in one cubic meter of water, and krill are often so abundant that they color the sea reddish-brown.
The source saysThey are frequently found in such abundance that they colour the sea a reddish-brown. ... the density of the animal can be as high as 30,000 individuals per cubic metreNote: "so abundant" for "such abundance"; "often" for "frequently"
The page saysMost of the larger Antarctic animals, such as seals, whales, seabirds, fish and squid, depend on them, directly or indirectly.
The source saysMost of the larger Antarctic animals (seals, whales, seabirds, fish and squid) depend on Antarctic krill, directly or indirectly.
The page saysIn winter, krill turn to other food: algae growing on the underside of the pack ice, detritus on the seafloor, or other animals in the water.
The source saysIn winter, krill have to use other food sources such as algae growing on the underside of the pack ice, detritus on the sea-floor or the other animals in the water.
The page saysLab studies show they can survive more than 200 days of starvation, and they shrink as they starve, burning their own body proteins as fuel.
The source saysLaboratory studies have shown that Antarctic krill can survive more than 200 days of starvation. ... 'Downsizing' enables Antarctic krill to use their own body proteins as a source of fuel. ... They shrink in length as they starve.
The page saysAfter a series of molts, adults look like two-year-old juveniles again, and in spring they mature once more.
The source saysAfter a series of moults they again resemble two-year-old juveniles ... In spring, adults once more begin to develop sexual characteristics and become mature before the spawning season.

Source
02

Animal Diversity Web, University of Michigan

Euphausia superba (Antarctic krill). Animal Diversity Web, University of Michigan.

The page saysKrill usually feed by using their chest legs to form a watertight basket around a pocket of water and food.
The source saysUsually, Antarctic krill feed by using their thoracic endopodites to create a watertight feeding basket, which encloses a pocket of food and water.Note: "chest legs" is a plain gloss of thoracic endopodites (branches of the thoracic legs)
The page saysWater is squeezed out sideways through fine bristles.
The source saysWater is then filtered out laterally by compression-filtration through setae.
The page saysThe phytoplankton (microscopic ocean plants) left in the basket is brushed forward into the mouth.
The source saysPhytoplankton remains caught in the feeding basket as water is filtered out, and is brushed forward by the setae into the mouth for ingestion.Note: the gloss is AAD's definition: "phytoplankton, which are microscopic ocean plants"
The page saysThey sit near its mouthparts, at its reproductive organs and at the base of its swimming legs, and they give off blue light.
The source saysThere are luminous organs called photophores located near the mouthparts, at the genitals (located on the cephalothorax), and at the base of the abdominal pleopods (which are the forked limbs these animals use for swimming). These photophores produce a blue light.

Source
03

Kawaguchi & Nicol 2015

Kawaguchi & Nicol (2015). Euphausia superba. The IUCN Red List of Threatened Species 2015: e.T64239743A64239951.

The page saysLeast Concern
The source saysLeast ConcernNote: read through GBIF's copy of the Red List per verify:quotes; category check, not the assessment's text

Source
04

Hill 2012

Hill (2012). Prospects for a Sustainable Increase in the Availability of Long Chain Omega 3s: Lessons from the Antarctic Krill Fishery. Omega-6/3 Fatty Acids.

The page saysadults mostly in the top 150 meters, but found as deep as 3,500 meters
The source saysAdult Antarctic krill occur mainly in the upper 150m of the water column 41 and are best known from open water habitats, but they also occur under sea ice 42 and at depths of upto 3,500m 41Note: the source writes the units with no space (150m, 3,500m); the profile adds the space, the same figures

Source
05

Grinnell et al. 1988

Grinnell et al. (1988). Eye/Photophore Coordination and Light-Following in Krill, Euphausia Superba. Journal of Experimental Biology.

The page saysphotophores on muscular stalks that aim their light away from incoming light
The source saysEight of the 10 photophores of the Antarctic krill, Ettphausia superba, are located at the ends of muscular stalks and exhibit coordinated orientation responses to incident white light; light emitted from the photophores is directed away from the incident light.Note: eight of the ten are on stalks; the stat does not say all of them are
The page saysA krill has ten photophores, organs that make light.
The source saysEight of the 10 photophores of the Antarctic krillNote: ADW: "luminous organs called photophores"
The page saysEight of the ten sit at the tips of muscular stalks.
The source saysEight of the 10 photophores of the Antarctic krill, Ettphausia superba, are located at the ends of muscular stalks
The page saysIn experiments, when white light shone on a krill, the stalks turned, pointing their light away from it, and the eyes turned at the same time.
The source saysEight of the 10 photophores of the Antarctic krill, Ettphausia superba, are located at the ends of muscular stalks and exhibit coordinated orientation responses to incident white light; light emitted from the photophores is directed away from the incident light. Moreover, eye rotation occurs synchronously with photophore movement.
The page saysRemoving the eyes, or covering the head with a hood, stopped the photophores moving together.
The source sayseye removal or covering the head with an opaque hood eliminated coordinated photophore movement
The page saysThe researchers concluded that krill need vision to aim their lights.
The source saysWe conclude that vision is necessary for light-following responses by the photophores.
The page saysKrill have ten photophores, organs that make light, and eight of them sit at the tips of muscular stalks.
The source saysEight of the 10 photophores of the Antarctic krill, Ettphausia superba, are located at the ends of muscular stalks
The page saysWhen white light shone on krill, the stalks turned, pointing the light they gave off away from it, and the eyes turned at the same time.
The source saysEight of the 10 photophores of the Antarctic krill, Ettphausia superba, are located at the ends of muscular stalks and exhibit coordinated orientation responses to incident white light; light emitted from the photophores is directed away from the incident light. Moreover, eye rotation occurs synchronously with photophore movement.
The page saysRemoving the eyes, or covering the head with a hood, stopped the photophores moving together, and the researchers concluded that krill need vision to do it.
The source sayseye removal or covering the head with an opaque hood eliminated coordinated photophore movement. We conclude that vision is necessary for light-following responses by the photophores.

Source
06

Dawson et al. 2018

Dawson et al. (2018). Turning microplastics into nanoplastics through digestive fragmentation by Antarctic krill. Nature Communications.

The page saysAntarctic keystone
The source saysAntarctic krill ( Euphausia superba , hereafter ‘krill’), a keystone species in the Antarctic ecosystem
The page saysFilter feeders may be the animals most likely to swallow microplastics (tiny pieces of plastic), because filter feeding is fairly unselective.
The source saysPlanktonic suspension and filter feeders may be the most susceptible to microplastic ingestion due to the relatively indiscriminate nature of this feeding strategyNote: "fairly unselective" for "relatively indiscriminate"; "may" kept; "because" for "due to"
The page saysA krill chews its food with its mandibles (jaws), then passes it into its stomach and gastric mill, where it is mixed with digestive enzymes and chewed again.
The source saysFood particles are retained on the basket and are then transported to the mandibles for mastication ... Food is then directed through the short oesophagus into the stomach and gastric mill where it is mixed with digestive enzymes for further masticationNote: "chews" and "chewed again" for mastication and further mastication
The page saysIn a lab study, researchers fed Antarctic krill plastic beads averaging 31.5 micrometers wide (a micrometer is a millionth of a meter).
The source saysTo determine the effect of ingestion on microplastic beads we exposed krill to a 4-day static renewal assay ... Beads in the stock suspension had a mean diameter of 31.5 µm
The page saysEvery krill ended up holding a mix of whole beads and fragments.
The source saysWe found all krill contained a mixture of whole PE microplastic beads and PE fragments
The page saysSome pieces were less than 1 micrometer across.
The source saysIngested microplastics (31.5 µm) are fragmented into pieces less than 1 µm in diameter.Note: "some pieces": the results give a mix of whole beads and fragments with a 7.1 µm mean, so not every piece was this small
The page saysThe authors think most of the grinding happened in the stomach and gastric mill.
The source saysThe bulk of plastic maceration presumably took place in the stomach and gastric millNote: "think" keeps "presumably"; "most of the grinding" for "the bulk of plastic maceration"
The page saysEarlier feeding studies had shown microplastics either passing through an animal unchanged or being small enough already to cross into its body.
The source saysPrevious feeding studies have shown spherical microplastics either; pass unaffected through an organism and are excreted, or are sufficiently small for translocation to occur.Note: "cross into its body" glosses translocation (the paper: to the haemolymph)
The page saysThe authors called krill's grinding a new pathway, which gives krill, and potentially other species, a new role in what happens to plastic in the ocean.
The source saysWe identify a new pathway; microplastics are fragmented into sizes small enough to cross physical barriers, or are egested as a mixture of triturated particles. ... introduces a new role of Antarctic krill, and potentially other species, in the biogeochemical cycling and fate of plastic

Source
07

Bar-On, Phillips & Milo 2018

Bar-On, Phillips & Milo (2018). The biomass distribution on Earth. Proceedings of the National Academy of Sciences.

The page saysA 2018 study of all the living matter on Earth, measured by the carbon in it, found Antarctic krill on a par with humans or cows.
The source saysthe Antarctic krill species Euphausia superba contributes ≈0.05 Gt C to global biomass ( 24 ), similar to other prominent species such as humans or cowsNote: 2018 is the paper's year (reference biomass-2018); "all the living matter on Earth" for "global biomass"; "on a par with" for "similar to"; Gt C is carbon mass, which the sentence names

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.