The most common and most likely answer to this crossword clue is the 4 letter word FLIT
I've seen this crossword clue in The Daily Telegraph
F
L
I
T
Buddy explains!

The straight part
We know that "Scamper" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case scamper = flit.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does FLIT mean?
FLIT noun- A fluttering or darting movement.
- A particular, unexpected, short lived change of state.
- A homosexual.
- To move about rapidly and nimbly.
- To move quickly from one location to another.
- To unpredictably change state for short periods of time.
- To move house (sometimes a sudden move to avoid debts).
- To be unstable; to be easily or often moved.
- Fast, nimble.