The most common and most likely answer to this crossword clue is the 9 letter word SCARECROW
I've seen this crossword clue in The Guardian
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More clues leading to the result SCARECROW
- Mind corn regularly vanishing during scatter? Here’s the answer
- Concern in South Carolina over line that's frightening?
- Animal crossing ploughed up acre in credit with fixture in field …
- Nurse carrying cocaine welcomed by female model
- Mark with sorrow, keeping Catholic back from crop protector
- Singular boast about keeping pest controller
- He doesn’t have to be smart to fool the birds
- Frightening figure emerging from vehicle in moment before commotion
- Surrey’s opener has wish to boast, intimidating fieldsman
- Surrey opener’s boast about anxiety for one out in the field
Buddy explains!

The straight part
We know that "He doesn’t have to be smart to fool the birds" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case he doesn’t have to be smart to fool the birds = scarecrow.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 SCARECROW mean?
SCARECROW noun- An effigy, typically made of straw and dressed in old clothes, fixed to a pole in a field to deter birds from eating seeds or crops planted there.
- A tall, thin, awkward person.
- Anything that appears terrifying but presents no danger.
- A person clad in rags and tatters.
- A bird, the black tern.
- To splay rigidly outward, like the arms of a scarecrow.