The youngest competitor at this year's Fieldays innovation centre is hoping investors will get on board with his invention that stops birds contaminating water supplies in tanks.
Twelve-year-old Brad Martin came up with his bird stop idea while living on a dairy farm his dad, Steve, worked on near Whangarei last year.
The farm had problems with birds getting into the water supply through the overflow pipe.
"It's important because bird crap carries over 60 different types of diseases," Brad said.
His answer to the problem? "It was pretty easy, I just used a ballcock, sinker and string."
Brad's invention, which won him the 2012 Central Northland Science Fair's top prize, is now up against a raft of other innovations that include remote-controlled drones that monitor farms, effluent separators and devices that send text messages to mobile phones when trough water supplies run low.
The Matarau Primary School student said he had sold a small number of bird stops to friends for $35 but was hoping an investor would help him with the patenting process.
For now he has no plans to get into science when he leaves school. "I want to be a farmer, dairy probably," he said.
Also vying for the top prize is 13-year-old Ayla Hutchinson of Inglewood High School, who designed a kindling cracker after her mum nearly chopped off a finger while cutting wood. The apparatus is a splitter head welded onto a metal plate. A piece of wood is placed on the splitter before being hit with a mallet to produce kindling.
Ayla has more than 80 orders for her invention. At $80 each that's $6400. "Not bad for a day's work," she said.