Proposals for massive five-figure fines and up to two years behind bars for people caught with illegal plants and animals have been slammed as excessive.

One user wrote on Government forums: “Whilst a fine is plausible, the amount is unjust. Also imprisonment is not the answer.

“Maybe a lifetime ban, name and picture be added to a database that is accessible by the necessary entities.”

The legislation would allow for fines of up to $50,000 as well as prison time.

But Peter Sanderson, a lawyer, highlighted that the legislation would criminalise people who were unaware they were in possession of prohibited species.

He said: “The problem is that, as they are invasive – and not recognisable in many cases.

“Somebody could be in possession of them without even knowing they are on their land.”

Mr Sanderson asked: “Do we really want to be criminalising people for ignorance of what is invasive?”

He said special defences should be added to the legislation.

Mr Sanderson added: “I believe a defence of ignorance needs to be added to the offences or, even better, that it only becomes an offence once somebody continues to possess after having been given a reasonable opportunity to dispose of it.”

Mr Sanderson said the legislation did not define “grow” and “cultivate” - which raised concerns that people could be charged for the growth of invasive species on their property.

He was speaking after the draft Invasive Alien Species Act was posted online for public debate earlier this month.

The legislation, designed to curb the spread of invasive species, proposed heavy penalties for anyone who imported or released a prohibited or restricted species.

Similar penalties were included for people who possess, breed, grow, buy or sell prohibited species – a list that included snakes and scorpions.

Members of the public would be allowed to possess restricted species – those already found on the island, but considered invasive or potentially problematic, such as lionfish or Brazilian pepper.

But people who bought, sold or traded them without a licence could face a $50,000 fine and a jail term under the proposed changes and only some restricted species could legally be bred or cultivated without a licence.

Several users suggested better public education about invasive species and one said that cash raised from fines should be used to support horticultural education.

One woman wrote: “We need more horticulturists, skilled landscapers - not slash-and-trash clear cutters - arborists, and botanists.

“Moreover, these are jobs that often appeal to students who have a lot to offer in terms of being hard-working problem-solvers, but aren't well suited to desk jobs.”

Users also discussed the species proposed for the lists and suggested species that should be added or removed.

Introduced bird species singled out for addition to the banned list included kiskadees, starlings and the yellow crowned night heron.

Other posters suggested cats and rabbits should face stricter regulation.

One poster said: “Domestic cats are excellent predators and will hunt small animals indiscriminately, including bluebird fledgelings.

“A specific law for domestic cats should be introduced prohibiting them from being allowed to roam outside unless on a lead. This may be unpopular, but it is necessary.”

One user argued that food-bearing species should not be considered invasive and highlighted that the rules would allow the Government to remove invasive species from private property.

The draft legislation also included a clause to allow the relevant Government minister to strike a deal with a landowner to help control an invasive species.

But a provision would allow the minister to apply to the Supreme Court “in extraordinary circumstances” when agreement could not be reached.