Official recognition that the spectacled flying fox is now an endangered species was bittersweet for those who lobbied for its change in status.

This week Environment Minister Melissa Price amended the list of threatened species — among the changes was an up-listing of the tropical fruit bat from 'vulnerable' to 'endangered' — four years after the CSIRO recommended a change.

Tropical and northern species in amended EPBC Act lists: Bramble Cay melomys (Mammal) — transferred from endangered to extinct category

Bramble Cay melomys (Mammal) — transferred from endangered to extinct category Spectacled flying fox (Mammal) — transferred from vulnerable to endangered category

Spectacled flying fox (Mammal) — transferred from vulnerable to endangered category Carpentarian rock rat (Mammal) — retained in endangered category

Carpentarian rock rat (Mammal) — retained in endangered category Mossman fairy orchid (Plant) — retained as critically endangered category

Mossman fairy orchid (Plant) — retained as critically endangered category Haines's orange mangrove (Plant) — included in critically endangered category

The species is in rapid decline.

CSIRO monitoring showed a 50 per cent loss between 2004 and 2017 and heatwaves this summer have further decimated the remaining population by an estimated 30 per cent.

"After the heat event, the species is probably closer to 'critically endangered'," CSIRO ecologist David Westcott said.

"[But] changing the listing doesn't change anything for the species, we actually have to engage in a process of recovery planning and implement actions before anything changes for the species.

"It's really just a permission to take the next step — and it's taking the next step that's fundamental for the species' recovery."

A recovery plan was adopted in 2010 but Dr Westcott said climate change has been detrimental to its effectiveness.

"We have impacts now at scales that even a few decades ago we would've struggled to imagine," Dr Westcott said.

"We're only just beginning to realise now just how much impact our lifestyles, our activities have right across the region and in places we couldn't imagine having any influence on it."

And it is not just the spectacled flying fox under threat, with several tropical species represented in the recent amendments to the Environment Protection and Biodiversity Conservation (EPBC) Act — most notably the extinction of the Bramble Cay melomys due to climate change.

The Bramble Cay melomys, which was endemic to a tiny island in the Torres Strait, has been declared extinct. ( Supplied )

"Certainly there are range of species that have come up on the listing recently here in the Tropics and that's a real flag for us that things are not as good as they could be in our part of the world," Dr Westcott said.

Decline in tropical species is 'the canary in the coalmine'

Professor Stephen Williams has studied wildlife biology in the Wet Tropics area for 25 years and is alarmed by the steady and ongoing decline of species in the hotter, lower elevation parts of the far northern mountain ranges.

Professor Stephen Williams has spent his career studying the wildlife of the Wet Tropics World Heritage Area in Far North Queensland. ( ABC News: Ben Deacon )

"Over the last 10 years many species of mammals, [in particular] marsupial possums and birds have systematically disappeared from the lower edge of their range and contracted to higher, cooler areas," Dr Williams said.

Dr Williams believed the current threatened species list does not represent the current reality.

"I think now we would have the evidence to start listing a whole lot of things that have been declining due to climate change," he said.

"The recent heat waves were intense even at the tops of the mountains so I'm dreading the potential impacts that may have already occurred.

"I suspect the next wave of extinctions is going to be mostly due to extreme events — extreme climate events like heatwaves."

And the Tropics are especially vulnerable to rising temperatures.

The ringtail possum is among numerous endemic tropical species in decline due to climate change. ( Flickr: peterhut )

"About 80 per cent of all the world's species occurs in the Tropics, so we've got a lot more to lose there," Dr Williams said.

"The animals and plants in the Tropics have evolved to a higher mean temperature but a low variability so they don't like extreme temperature in either the cold or hot direction.

"A lot of tropical species are much closer to the edge of the tolerances, so they very much are the 'canary in the coalmine' for the world in what's going to start happening with climate change.

"The fact that we're now seeing things endangered occur in places that you would've thought to be pretty secure, that's the scary bit."

Lowland rainforest in the Wet Tropics area. ( Supplied: Mike Trenerry )

Rainforests ignored due to reef exposure

Professor Williams believed the perilous state of tropical rainforests was being overlooked in the wake of attention directed towards the Great Barrier Reef.

"Our mountainous, tropical ecosystems are every bit as endangered as the reef, but it's less obvious to the public because you don't have something as obvious as coral bleaching," Dr Williams said.

"The species are slowly disappearing and no-one is noticing.

Coral bleaching was discovered on the Great Barrier Reef during a survey in 2017. ( Supplied: Reef and Rainforest Research Centre )

"If you look at a reef, it's turned white and it's dying, it's really visually obvious there's been a big impact but if I took someone into a patch of rainforest, the ecosystem is still there — you can still see birds, or butterflies.

"So, to someone who hasn't spent a lot of time there, it's not immediately obvious that the system is in trouble.

"The fact is, there might be animals there, but there are bird calls that you just never hear anymore but unless you know them, you don't pick it up."