Flighty creature trapped in Luke's trellis (7)

I believe the answer is:

kestrel

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'flighty creature' is the definition.
'kestrel' can be an answer for 'creature' (kestrel is a kind of animal). I'm unsure of the 'flighty' bit.

'trapped in luke's trellis' is the wordplay.
'trapped in' indicates the answer is hidden within the clue.
'KESTREL' is hidden within 'lukes trellis'.

Can you help me to learn more?

(Other definitions for kestrel that I've seen before include "High flier" , "Bird of prey" , "Les, trek around the bird" , "It takes mice" , "Predator" .)

I've seen this clue in The Telegraph.

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