The Agricultural Aviation Association says the reputation its pilots have of being the cowboys of the sky has made the industry less attractive for new recruits.
The industry, which provides aerial topdressing and spraying services, is holding its conference in Rotorua.
Association chairman Graeme Martin says despite economic conditions improving with increased fertiliser demand in the past 12 months, some pilots have left.
He says about six fixed-wing pilots have left the industry in the past 12-18 months and while some are likely to be leaving because their business is not sustainable, others have gone because they've had a good year and determined that it is the right time to get out.
Mr Martin says a lot of effort has been going into attracting pilots into the industry and redefining the industry so the pilots are defined as professional, not just ag, pilots.