THE ANIMAL FILES

Common carp

Cyprinus carpio

The muddy mouthful is sorted before the meal is swallowed.

Common carp take food and sediment into the mouth by suction, then use taste and internal sorting to retain useful material. Their toothless mouths pass food toward pharyngeal teeth farther back.[1]

Follow the evidence ↓
Common carp
Image: Dezidor · Commons · CC BY-SA 3.0
Feeding zone
Often in or near bottom sediment[1]
Diet
Omnivorous, using plants and animals[1]
Food processing
Pharyngeal teeth behind a toothless mouth[1]

The pond bottom is a search surface

Carp favour slow or standing water with soft, vegetated sediments. They forage for roots, seeds and bottom-dwelling animals such as worms, molluscs and crustaceans.[1]

Suction starts a sorting process

A carp can draw in sediment by suction, then move material between mouth and pharynx while sorting food by taste and size. Internal structures help retain selected items and reject other material. Spat-out sediment can make the water cloudier, linking a small feeding action with the appearance of the pond.[1]

No teeth at the lips does not mean no grinding

Common carp lack teeth in the oral jaws, but possess pharyngeal teeth farther back that crush or grind food. Their feeding system is therefore not fully visible when the mouth opens.[1]

A COMMON MIX-UP

Does rooting in mud mean eating only mud?

No. Sediment is part of the material taken in during food searching and sorting. The diet includes both plant and animal items, and unsuitable material can be expelled after the fish has selected food.[1]

TRY A LITTLE REASONING

Why might feeding carp make the water look different?

Reveal the explanation

The fish disturbs sediment and can spit it back out while sorting food. Suspended particles change water clarity, so the visible cloud can be a consequence of the feeding process rather than the food itself.[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 — Common carp (fixed revision; adapted and translated)
  2. NCBI Taxonomy — Cyprinus carpio (identity and classification)

Last fact check:

One discovery leads to another

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