The group of scientists signed a letter to the prime minister, urging him to increase spending and support laws that would prevent the natural world from further devastation.

The federal government is due to announce a 10-yearly legislated review of the Environmental Protection and Biodiversity Conservation Act this week.

Three native Australian species have become extinct in the past decade and another 17 could follow in the next 20 years, according to the letter. More than 1,800 Australian plants and animals are formally listed as "threatened with extinction", but the scientists say the real figure is much higher than that.

"Our current laws are failing because they are too weak, have inadequate review and approval processes, and are not overseen by an effective compliance regime," the scientists said in an open letter published on Monday.

"Since the laws were established (in 1999), 7.7 million hectares of threatened species habitat have been destroyed. That's an area larger than Tasmania. Meanwhile, the number of extinctions continues to climb, while new threats emerge and spread unchecked."

Environmental law was a point of difference at this year's election, with Morrison pledging to limit "green tape" that he said cost jobs while the opposition Labor Party promised a new environment act and a federal environment protection authority.

Lesley Hughes, a distinguished professor of biology at Macquarie University and a signatory to the letter, said on Monday environmental protections in Australia had been consistently wound back over the past decade, usually by conservative governments.

She said such moves were having a significant impact on native species, pointing to the 2016 state of the environment report that found Australia was facing multiple environment changes and lacked a clear national policy that protected the country's national heritage.

A World Wildlife Fund assessment ranked eastern Australia as one of the world's top 11 deforestation hotspots. Australia was the only developed country on the list.

"It's a very grim picture," Hughes said. "This letter is a pre-emptive strike to say this is an opportunity to do better, this is not an opportunity to weaken and dilute the existing weak laws."