Gum Air

An air operator must provide a life preserver for each person when operating from water and for long flights over water.

Also, the air operator must carry survival equipment capable of providing a means for starting a fire, providing shelter, purify/providing water and visually signalling distress given the geography, season and anticipated seasonal climate changes of the area over which you will be flying. Ask the pilot where this equipment is stowed and how to get at it.
Consider carrying safety equipment of your own, such as some strong cord, a signalling mirror and extra clothing. Take suggestions form survival books you have read. Ask about the location and operation of the emergency locator transmitter (ELT). The ELT is a battery-powered radio that transmits an emergency signal to enable search aircraft to locate you in the event of a crash.