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Research paper says koalas are happy in harvested north coast forests

The NSW timber industry’s harvesting practices on the north coast have been vindicated in a research paper released yesterday. The Natural Resources Commissioner, Professor Hugh Durrant-Whyte, said koala density was higher than anticipated in the surveyed forests and was not reduced by selective harvesting. Source: Timberbiz

“This research is the most comprehensive conducted of its type in NSW to date,” he said.

The research into the koala response to forestry has found that the nutritional quality of trees is critical for koala survival and that selective harvesting did not have an adverse impact upon koala numbers on surveyed north coast state forests.

This is due to the types of trees left after harvesting as some trees such as tallowwood have higher nutritional quality than others such as blackbutt.

Timber NSW CEO Maree McCaskill said the findings “totally vindicates the skilful ability of the forest managers to care for the land under their responsibility and protect koalas”.

Not only do koalas successfully coexist with selective forest harvesting but the research found no difference in koala density between National Parks and the state forest harvest areas on the North Coast.

“That finding will upset the eco-warriors but will not surprise the forest industry,” Ms McCaskill said.

“Enormous care and expertise is exercised by NSW forest ecologists and they deserve credit for the role they play.

“The public gets tired of environmental organisations who constantly predict catastrophe and extinction, causing panic and alarm. People like to know the truth and this independent scientific research should reassure everyone in NSW that the iconic koala is not in the least bit threatened by forestry.

“The industry rarely agrees with the NRC and its reports but on this occasion, we gave it a tick”.

The research included tracking GPS-collared koalas. Even at old intensively harvested sites (which pre-dated modern selective harvesting practices) koalas were present. Koalas were found to be using the full range of the available habitats five to 10 years post-harvest, including regenerating forest.

“As the NRC pointed out, regulation mandates the retention of priority koala browse trees as well as other habitat protection within working forests,” Ms McCaskill said.

“In fact, native forest tree harvesting, and regeneration occurs under very strict regulation and highly skilled forest ecologists and forest scientists work fulltime to ensure flora and fauna are protected.”

The existing forestry rule set mandates the retention of priority koala browse trees as well as other habitat protections.

The findings have emerged from a three-year research program independently overseen by the NSW Natural Resources Commission.

With support from a panel of experts in koala ecology and forest science, the Commission selected eminent scientific researchers from the Australian National University, Western Sydney University and the Department of Primary Industries Forest Science Unit to undertake the research. The researchers investigated koala movement, occupancy, density, diet and the nutritional quality of koala habitat on state forests.

“This research suggests that it’s not so much about tree size but having a good tree species mix post-harvest to maintain koala numbers,” Professor Durrant-Whyte said.

“However, north coast forests are diverse, so I caution applying these findings to other areas without further research.

“The Commission has also engaged researchers to investigate how koalas are recovering from the 2019/20 wildfires. There remain many critical knowledge gaps about koala populations across NSW, but this piece of research helps to fill in one piece of the puzzle of one of our iconic species,” he said.

“I am concerned however, there are greater threats to the long-term survival of koalas in NSW’s forests. In particular, climate change is a threat to the future integrity of koala habitats due to increased frequency of wildfire and prolonged periods of heat stress.”

The NSW Government tasked the Commission to deliver the independent research program in 2018. The research was funded and undertaken as part of the whole-of-government NSW Koala Strategy 2018-21.

Other key research findings include:

  • the average nutritional quality of NSW north coast hinterland forests for koalas is relatively low compared with forests in other locations across the koala range from Queensland to South Australia, which restricts the landscape’s capacity to support koalas
  • koala density was mostly similar between state forest and national park sites that included similar forest types, and regrowth from historical harvesting.