I thought of some cool possible calls while on patrol.
1. Medevac of injured fisherman or fisherman fell off boat and the boat has lost him.
2. Raton canyon rapid river rescue of kayakers
3. Person fell ill on cruise ship maybe?
4. Ship taking on water and you need to deliver a pump so they can get the water out.
5. Boats engine stopped and needs some repair parts to get to port, deliver the parts to them.
6. Ship ran aground near the coast and you if in helicopter over sea the evacuation of the boat while a ground team retrieves the passengers. Possible injured person from the initial grounding of ship and they need to be taken by heli to hospital or something. If in boat then you take the passengers to shore to waiting first responders. Something along that line.
Hope this helps with some call ideas!