Forests around the world are shrinking and birds are among the few animals benefiting from the dramatic death of trees, a decade-long study reveals.

The study of how 631 animals are reacting to the decline of trees from Murdoch University reveals that some animals are threatened to the point of extinction, while common bird species actually grew in number.

Murdoch University wildlife biologist Trish Fleming said although the impacts of climate change and habitat clearing are known to damage the forest trees, there was a lack of knowledge about the impact on animals within the forest.

“We’d assume that everything would fail from a lack of trees, but some species are doing really well,” Ms Fleming said.

More than 186 bird species are thriving and some birds, such as bats or woodpeckers have a higher survival rate because the reduction in trees creates more open canopies for them, she adds.

The Department of Biodiversity Conservations and Attractions describes Australia as a ‘mega-diversity’ centre of plants and animals, being among the list of only 17 on the globe.

Ms Fleming says the new research found a “concerning trend” linking the death of trees to the death of certain animals that rely on nectar or pollen to survive.

#Returnto1616 is bringing hope for many native species now threatened or extinct from the Australian mainland. Learn more about our ecological restoration of Dirk Hartog Island on ABC's @RadioNational. https://t.co/wpoJYxiCuR

— Parks and Wildlife Service, Western Australia (@WAParksWildlife) March 31, 2021

“When you lose all pollen eaters,” she says.

“The trees then don’t produce enough seeds or even another generation of trees at all.”

Land clearing for agricultural or urban purposes can cause disruptions to tree growth and wipe out plant species, Ms Fleming warns.

“This if fine if you want to live in a concrete jungle,” She said.

“But eventually there will be no animals or plants in sight.”

The study also observed 33 mammals and found the loss of trees had negative effects on those that use trees as refuges.

“This is a real wakeup call if we want to maintain those unique animals that make our forest ecosystems so special,” Ms Fleming said.

The study was published in the journal of Biological Reviews.