WHAT would you do if you'd killed and decapitated a protected species?

After one Ipswich man killed a saltwater crocodile near Townsville, he decided to keep the evidence, its head, in his freezer.

Trent Alan Theuerkauf, who lives at Gatton and Esk, pleaded guilty at the Ipswich Magistrates Court to decapitating and skinning a two-and-a-half metre saltwater crocodile north of Townsville.

The court heard late last year the body of a headless and skinned crocodile was found at Bushland Beach, a northern suburb of Townsville.

It had been left in an area popular with tourists and locals.

A genetic sample was taken from the dead crocodile and analysed at the UQ veterinary clinic.

Following a joint investigation between the police and the State Government, the court heard police raided the property of Ipswich man Theuerkauf, 24, who was in Townsville at the time.

Inside the house they found a severed crocodile head stored in a freezer and a crocodile skin in the house.

Police also found six kangaroo skins and the shell of an endangered green turtle. The court heard Theuerkauf had no licence for the items.

They also discovered a number of illegal fireworks at the house.

Police viewed Theuerkauf's phone where they found photos of him with a crocodile carcass.

Genetic samples were taken from the skin and head which matched the body left at Bushland Beach. It was the first time genetic analysis was used in a similar case.

Theuerkauf pleaded guilty at the Ipswich Magistrates to illegally possessing explosives, and possessing a restricted animal carcass.

Magistrate Donna McCallum fined him $7000 and ordered the forfeiture of the crocodile skin and head, the kangaroo skins, the turtle shell and the fireworks which were in the possession of the police.