Targeted speculators? (5)

I believe the answer is:

bulls

I'm a little stuck... Click here to teach me more about this clue!

'speculators?' is the definition.
The definition and answer can be both people as well as being plural nouns.
Perhaps they are linked in a way I don't understand?

I can't explain the rest of the clue.

Can you help me to learn more?

(Other definitions for bulls that I've seen before include "Male whales" , "Male animals" , "Male cattle" , "Adult males of domestic cattle" .)

I've seen this clue in the Evening Standard.

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