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What the sources say

European EelAnguilla anguilla

Every figure, record and mechanism on the European Eel profile was written from a source, and this is the working table behind it: 53 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

FishBase

Anguilla anguilla summary page. FishBase.

The page saysthought to spawn only in the Sargasso Sea
The source saysActual spawning has never been observed but is believed to occur solely in the Sargasso SeaNote: tagline; body
The page saysits spawning has never been observed
The source saysActual spawning has never been observedNote: tagline
The page saysRivers, lakes and coasts from Scandinavia to Morocco, including the Baltic, Black and Mediterranean seas
The source saysAtlantic coast from Scandinavia to Morocco; Baltic, Black and Mediterranean Seas; rivers of North Atlantic, Baltic and Mediterranean seasNote: stats.habitat
The page saysRivers, lakes
The source saysInhabits all types of benthic habitats from streams to shores of large rivers and lakesNote: stats.habitat
The page saysspawning area in the Sargasso Sea
The source saysSpawning area in western Atlantic (Sargasso Sea)Note: stats.habitat; body 'in the western Atlantic'
The page saysAdults leave European rivers and cross the Atlantic to the Sargasso Sea
The source saysWhen sexual maturity is reached they leave the river.Note: FAQ 1
The page saysgrows up in rivers, lakes and estuaries
The source saysThey enter the estuaries and colonize rivers and lakesNote: body
The page saysActual spawning has never been observed.
The source saysActual spawning has never been observedNote: body
The page saysEel larvae, called leptocephali, are transparent and ribbon-like.
The source saysEel larvae (leptocephali) are transparent ribbon-like.Note: body
The page saysThe Gulf Stream carries them to the coasts of Europe over 7 to 11 months.
The source saysThey are brought to the coasts of Europe by the Gulf Stream in 7 to 11 months timeNote: body
The page saysglass eels, 6 to 8 cm long, cylindrical and see-through or slightly coloured
The source saysglass eels (6-8 cm length, cylindrical in shape and transparent to slightly pigmented in colour)Note: body
The page saysThese enter estuaries and colonise rivers and lakes, though some stay in estuaries and coastal waters to grow up.
The source sayssome individuals remain in estuaries and coastal waters to grow into adultsNote: body
The page saysA long feeding stage follows, from yellow eel to silver eel, lasting 6 to 12 years in males and 9 to 20 years in females.
The source saysThe glass eel stage is followed by a long feeding period (from the yellow to the silver eel stage) lasting 6-12 years in males (Ref. 6125 ) and 9-20 years in femalesNote: body
The page saysdark on the back and silver on the belly, with a black lateral line and enlarged eyes
The source saysYellow eels eventually lose their pigmentation, becoming dark dorsally and silver ventrally (called silver eels). Silver eels are also characterized by a clear contrasting black lateral line and enlarged eyesNote: body
The page saysfacultative air-breather
The source saysFacultative air-breathing (Ref. 126274 )Note: body; the gloss defines the term
The page saysA common length for females is 50 cm
The source sayscommon length :50 cm TL (female)Note: body; FAQ 3 'half a metre'
The page saysmales can grow up to 50 cm
The source saysMale eels can grow up to 50 cm TLNote: body
The page saysa maximum of 133 cm for a female
The source says133.0 cm TL (female)Note: body; FAQ 3
The page saysa maximum published weight of 6.6 kg
The source saysmax. published weight: 6.6 kgNote: body; FAQ 3
The page saysAverage life span is usually 15 to 20 years.
The source saysAverage life span is usually 15-20 yearsNote: body
The page saysThe range runs along the Atlantic coast from Scandinavia to Morocco and into the Baltic, Black and Mediterranean seas.
The source saysAtlantic coast from Scandinavia to Morocco; Baltic, Black and Mediterranean SeasNote: body
The page saysThe fish nobody has seen spawn
The source saysActual spawning has never been observedNote: heading
The page saysbelieved to breed only in the Sargasso Sea
The source saysActual spawning has never been observed but is believed to occur solely in the Sargasso SeaNote: body
The page says133 cm as the maximum total length for a female
The source says133.0 cm TL (female)Note: FAQ 3
The page says6.6 kg as the maximum published weight
The source saysmax. published weight: 6.6 kgNote: FAQ 3
The page saysA common length for a female is 50 cm.
The source sayscommon length :50 cm TL (female)Note: FAQ 3
The page saystags: river
The source saysInhabits all types of benthic habitats from streams to shores of large rivers and lakesNote: task #1267

Source
02

Human Ageing Genomic Resources, AnAge

AnAge entry for Anguilla anguilla. Human Ageing Genomic Resources, AnAge.

The page saysThese silver eels do not eat on the way to the Sargasso Sea.
The source saysAfter transformation from juvenile to adult stage they do not eat and feature elevated corticosteroids while they migrate to the Sargasso Sea to spawnNote: body
The page saysKeeping an eel in captivity stops the migration and greatly extends its life
The source saysPreventing migration by keeping animals in captivity significantly extends lifespanNote: body; FAQ 2
The page saysa female called Putte, generally assumed to be a European eel, died at a museum in Sweden at about 88
The source saysOne female called "Putte", generally assumed to be a European eel, died at Halsinborgs Museum in Sweden at about 88 years of ageNote: body; FAQ 2
The page saysAnAge's maximum is about 88 years
The source saysMaximum longevity 88 years (captivity)Note: FAQ 2
The page saysWild eels die after their first spawning.
The source saysIn the wild, these semelparous animals die after first spawningNote: FAQ 2
The page saysweightKg: 3.6
The source saysAdult weight 3,629 gNote: task #1267: AnAge average adult weight rounded; Light, where the name guess gave Medium. FishBase's 6.6 kg is a maximum

Source
03

Animal Diversity Web

Anguilla anguilla. Animal Diversity Web.

The page saysMostly aquatic invertebrates, but almost any food it can find
The source saysTheir primary food source is aquatic invertebrates, but they will eat essentially any food they can findNote: stats.diet
The page saysThe diet is broad.
The source saysAdult eels have a fairly broad dietNote: body
The page saysAdults mostly eat aquatic invertebrates, but they will eat essentially any food they can find, even things that are already dead.
The source saysTheir primary food source is aquatic invertebrates, but they will eat essentially any food they can find-- even dead organismsNote: body

Source
04

Wright et al. 2022

Wright et al. (2022). First direct evidence of adult European eels migrating to their breeding place in the Sargasso Sea. Scientific Reports.

The page says5,000 to 10,000 km
The source saysa distance of 5000 to 10,000 km across the Atlantic Ocean to the Sargasso SeaNote: tagline, superpower, FAQ 1, body
The page saysSwims 5,000 to 10,000 km across the Atlantic to spawn
The source saysAs an adult, the European eel undertakes the longest spawning migration of all anguillid eels, a distance of 5000 to 10,000 km across the Atlantic Ocean to the Sargasso SeaNote: superpower; FAQ 1
The page saysAs an adult it makes the longest spawning migration of any anguillid eel: 5,000 to 10,000 km across the Atlantic.
The source saysAs an adult, the European eel undertakes the longest spawning migration of all anguillid eels, a distance of 5000 to 10,000 km across the Atlantic Ocean to the Sargasso SeaNote: body
The page saysalmost 100 years since Johannes Schmidt proposed the Sargasso Sea as the breeding place from surveys of larvae
The source saysdespite the passage of almost 100 years since Johannes Schmidt proposed the Sargasso Sea as the breeding place of European eels on the basis of larval surveysNote: body
The page saysno eggs or spawning adults had ever been sampled there
The source saysno eggs or spawning adults have ever been sampled there to confirm thisNote: body; dated to the 2022 study
The page saysfitted satellite tags to 26 eels from rivers in the Azores
The source saysWe attached satellite tags to 26 eels from rivers in the Azores archipelagoNote: body
The page saysFive tags surfaced inside the Sargasso Sea's boundaries
The source saysFive of the pop-up locations were within the Sargasso Sea boundariesNote: body
The page saysone eel was located inside the presumed breeding area
The source saysone eel was located within the presumed breeding areaNote: body
The page saysIt was the first direct evidence of adult European eels reaching it.
The source saysours is the first direct evidence of migrating adult European eels reaching the presumed breeding place in the Sargasso SeaNote: body
The page saysThe tagged eels averaged 6.8 km a day
The source saysmean 6.8 km dayNote: blockquote
The page sayseels may make a long, slow trip at depth that saves energy and lowers their risk of dying
The source saysThe data therefore support the hypothesis that, rather than make a rapid migration to spawn at the earliest opportunity, European eels may instead make a long, slow spawning migration at depth that conserves their energy and reduces mortality riskNote: blockquote
The page saysat 95% since the 1980s
The source sayssuffered a 95% decline in recruitment since the 1980sNote: body; dated to the 2022 study
The page saysA 2022 study
The source says© Crown 2022, corrected publication 2022Note: body; the study's publication year
The page saysThe 2022 study
The source says© Crown 2022, corrected publication 2022Note: body; the study's publication year
The page saysTagged European eels headed for the Sargasso Sea at an average of 6.8 km a day
The source saysmean 6.8 km dayNote: vibe.reason
The page saysin what the data suggest is a long, slow trip at depth
The source saysThe data therefore support the hypothesis that, rather than make a rapid migration to spawn at the earliest opportunity, European eels may instead make a long, slow spawning migration at depth that conserves their energy and reduces mortality riskNote: vibe.reason

Source
05

Pike, Crook & Gollock 2026

Pike, Crook & Gollock (2026). Anguilla anguilla. The IUCN Red List of Threatened Species 2026: e.T60344A288387541.

The page saysCritically Endangered
The source saysIUCN Red List category: Critically Endangered (CR).Note: stats.conservationStatus; body

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.