THE ANIMAL FILES

European eel

Anguilla anguilla

A continental life can end with an ocean journey.

The European eel passes through strikingly different stages, from transparent young near the coast to the silvering migratory form.[1]

Follow the evidence ↓
European eel
Image: mr_capgras · Commons · CC BY 4.0
Changing the body
Glass, yellow and silver stages[1]
More than freshwater
Fresh, brackish and marine routes[1]
Shelter and night feeding
Scent helps guide feeding[1]

Changing the body

Transparent glass eels develop into later yellow and silver stages. Silvering includes larger eyes, silver flanks and a lighter belly.[1]

More than freshwater

Many eels grow in continental fresh or brackish water before migrating toward the Sargasso Sea. Others remain in marine water or move repeatedly between salinities.[1]

Shelter and night feeding

Feeding occurs mainly at night, guided partly by scent. Plants and narrow rocky spaces provide shelter.[1]

A COMMON MIX-UP

Must every European eel grow up in fresh water?

No. Eels can grow in brackish or marine habitats, and some move between salinities.[1]

TRY A LITTLE REASONING

Why can a silver individual look unlike a yellow eel without being another species?

Reveal the explanation

Silvering is a developmental transition associated with migration. Changes of eyes and colour need to be interpreted within that sequence.[1]

Sources & editorial notes

Adapted and translated from the cited Wikipedia revisions, with source-linked reasoning. Image credit and licence are listed separately above.

Adapted and translated from Wikipedia contributors; exact revisions are linked below. CC BY-SA 4.0

  1. Wikipedia contributors — European eel (cited revision)
  2. NCBI Taxonomy — Anguilla anguilla

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