In island country group in retreat broods (9)

I believe the answer is:

incubates

'broods' is the definition.
('incubate' can be a synonym of 'brood')

'in island country group in retreat' is the wordplay.
'island country' becomes 'Cuba' (Cuba is an island).
'group' becomes 'set'.
'in retreat' says the letters should be written in reverse.
'set' written backwards gives 'tes'.
'in'+'cuba'+'tes'='INCUBATES'

I've seen this clue in The Times.

Want a hint initially instead of a full solution? Install my app