Just as a scavenger bird (the crow) possesses knowledge that would benefit the predator (the hunter) but remains silent, a wise person possesses 'secrets' (inner thoughts, spiritual warnings, or communal knowledge) that they must not share with those who might exploit them. Silence is a form of protection. Sharing everything leads to being used by others' agendas.
The crow knows who is dead, but it does not tell the hunter. Spiritual secrets must be kept to maintain power. Not all knowledge is for public distribution; silence is your greatest shield.