If another boat signals their intention to pass you from astern, you should answer with the same signal if in agreement and maintain course and speed.
A motorboat approaches you head-on and sounds one short blast. You would prefer to pass the boat on your starboard right side. Five or more blasts is the signal that you should you use to indicate your disagreement.
A common signal sound to pass another boater is one prolonged blast followed by two short blasts on a horn or whistle. This signal indicates that you intend to pass on the other boat's starboard side. Make sure to maintain a safe distance and communicate your intentions clearly to avoid collisions.
5 or more blasts
answer with same signal and continue maintain course and speed
You should pass a fishing boat with minimum wake and away from fishing lines.
Proper procedure for using hand held visual distress signal flare
You should pass a fishing boat with minimum wake and away from fishing lines.
You should already be aware of a boat approaching from astern ... your head needs to be on a swivel as the pilot at all times. You need to know everything about your surroundings. If you hear this signal you should probably slow down and let them pass safely. Don't crowd them or try to out run them.
Use your turn signal to both pull out of and return into the lane. Motorists should not signal their intention to pass by flicking their high beams.
The same way you should pass any other vessel.
Boats normally pass on the port (left) side. The other boater may use a signal horn.