Exclusion zone where spiders rule? (2-3,4)

I believe the answer is:

no-fly zone

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'exclusion zone' is the definition.
(I know that no-fly zone is a type of exclusion zone)

I can't explain the rest of the clue.

Can you help me to learn more?

(Other definitions for no-fly zone that I've seen before include "Area over which aircraft are forbidden" , "Area banned to aircraft" , "Area out of bounds to aircraft" , "Airspace in which (military) planes are forbidden" , "Airspace where no aircraft can go" .)

I've seen this clue in The Telegraph.

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