THE ANIMAL FILES

Marsh frog

Pelophylax ridibundus

The tadpole’s menu is not the adult frog’s menu.

The marsh frog connects flexible habitat use with a changing diet. Adults wait for small animals, while young tadpoles feed largely on algae and detritus before their menu shifts. Its calling males provide another clue to a life organised around water, even when much adult hunting takes place at the water’s edge or on land.[1]

Follow the evidence ↓
Marsh frog
Image: Christian Fischer · Commons · CC BY-SA 3.0
Adult strategy
Often waits for prey to come within reach[1]
Calling equipment
Males inflate paired vocal sacs[1]
Early tadpole diet
Mostly algae and detritus[1]

Flexible water use is not a single address

Marsh frogs occur in still and flowing waters, including ponds, lakes and rivers. Warm water and surrounding vegetation can be important parts of the setting.[1]

A call has a context

Male marsh frogs use inflated vocal sacs while calling. Mating calls attract females, while shorter territorial calls can be directed at other males. The sound therefore carries different social tasks.[1]

Metamorphosis changes the feeding role

Adults take mainly invertebrates and can also eat small vertebrates, including other frogs. Early tadpoles rely much more on algae and detritus, adding more animal material as development proceeds.[1]

A COMMON MIX-UP

Do all stages of a marsh frog eat the same food?

No. The largely algal and detrital diet of early tadpoles differs from the adult’s predatory feeding. The shift is gradual during development, not proof that a tadpole and a frog must represent unrelated animals.[1]

TRY A LITTLE REASONING

Why might a water sample and a bank-side observation suggest different diets?

Reveal the explanation

They may sample different life stages. Bottom-foraging tadpoles and adult ambush hunters use different foods, so age must be considered before combining observations into a single account of what the species eats.[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 — Marsh frog (fixed revision; adapted and translated)
  2. NCBI Taxonomy — Pelophylax ridibundus (identity and classification)

Last fact check:

One discovery leads to another

American bullfrogA pond chorus is a moving social scene.Aquarana catesbeiana ↗Common frogOne pond, two very different menus.Rana temporaria ↗Moor frogA male’s blue breeding colour is a brief appearance, not its year-round coat.Rana arvalis ↗