THE ANIMAL FILES

Long-tailed weasel

Neogale frenata

A black tail tip remains when the winter coat turns white.

Long-tailed weasels hunt small animals and use existing burrows for shelter. Northern populations can grow white winter fur while retaining a black tail tip. Their narrow bodies and scent-based searching help connect above-ground movement with prey hidden under cover.[1]

Follow the evidence ↓
Long-tailed weasel
Image: JoernHauke · Commons · CC BY-SA 3.0
A persistent tail mark
The tail keeps its black tip in white winter coats.[1]
Shelter already excavated
Abandoned burrows are commonly used.[1]
Searching and handling prey
Head movements help sample scent.[1]

A persistent tail mark

Summer fur is brown above and pale below, while northern winter coats can become white. The black tail tip remains, distinguishing this change from a body becoming uniformly white. Seasonal appearance varies across the species' broad range.[1]

Shelter already excavated

Dens occur in existing rodent holes, beneath stumps or among rocks. A chamber can be lined with straw and prey fur. The weasel need not excavate the entire tunnel system to obtain a place for resting and raising young.[1]

Searching and handling prey

While stalking, the animal moves its head side to side to pick up prey scent. Rodents are important, with birds, reptiles and other prey also recorded. Some food can be stored, separating the moment of capture from later consumption.[1]

A COMMON MIX-UP

Does white winter fur remove the black tail tip?

No. In the described northern winter coat, the black tip remains.[1]

TRY A LITTLE REASONING

Why would finding the weasel inside a rodent tunnel not show that it dug the tunnel?

Reveal the explanation

It commonly uses abandoned burrows, so occupation and excavation can belong to different animals.[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 — Long-tailed weasel (cited revision)
  2. NCBI Taxonomy — Neogale frenata

Last fact check:

One discovery leads to another

FerretA “war dance” can be an invitation to play.Mustela putorius furo ↗Least weaselA slender body follows prey into its own tunnels.Mustela nivalis ↗European badgerAn underground home needs bedding, not just tunnels.Meles meles ↗