A wildlife officer who smashed an animal smuggling operation involving more than 90 reptiles which were being mailed to New South Wales has slammed those trying to profit from the illegal trade.

A West Australian man was last week fined $13,000 after pleading guilty to more than 30 charges of taking and transporting native wildlife.

The court heard he and two associates went on a 2,000-kilometre road trip from Perth to the Kimberley to collect rare and sought-after reptiles before mailing them to a buyer in NSW.

The animals were intercepted, however 15 were found dead.

Department of Parks and Wildlife investigating officer Peter Carstairs said the animals were horribly treated.

"It was cruel how they were packaged," he said.

"They were put into small bags and then put into a cardboard box and that was sealed within a postage bag, so there was no air for these reptiles, and a number of animals [were] in each package," he said.

"These people are just trying to make money. They claim to be reptile enthusiasts but you really have to question their integrity when they're doing this kind of thing."

The court heard the 92 animals, including geckos, monitors and a rare Pilbara olive python, were collected from bushland in February last year.

They were then tightly wrapped in plastic and posted from Broome and Derby.

The plot was uncovered after post office staff in Broome noticed a package was moving and contacted police.

Reptiles worth thousands on black market

Most of the packages were intercepted at the post office, but about a dozen were seized in NSW after reaching their destination.

"Some of the animals had died within a few hours of them going into the bags, and some of the others were very dehydrated and needed veterinary care and did not recover well enough to be released," he said.

The man pleaded guilty in the Joondalup Magistrates Court on Friday and could have faced a maximum $120,000 fine for taking protected fauna, but was handed a $10,000 penalty plus additional fines for other charges.

A co-accused, aged 16 at the time of the offences, was given a spent conviction, while the third man charged over the operation was fined $5,000 earlier this year.

Mr Carstairs said the men stood to make a lot of money from the smuggling operation.

"Some of these species can be worth up to $3,000 domestically, but if they do manage to get them overseas then they can be worth up to 60 per cent more," he said.