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Opinion: Vic Jurskis – Koalas are feasting in our new growth forests

There was nothing new or unexpected about the recently announced NSW Natural Resources Commission research on timber harvesting and koalas. What shocked me was the response from Timber NSW.

Timber NSW said: “The industry rarely agrees with the NRC and its reports but on this occasion, we gave it a tick”. Source: Australian Rural & Regional News

This puts me in mind of the proverbial bloody chook, gratefully following Uncle Joe Stalin to get a few grains of wheat after he’d brutally plucked its feathers.

There’s nothing in the NRC report that actually deserves a tick. It’s a well-established historical and scientific fact that koalas are an irruptive species which responds positively to soft new growth.

Nearly a century ago, childrens’ author Dorothy Wall seemed to have a better grasp of their basic ecology than our modern experts. She wrote that Blinky Bill’s mother “climbed down the tree, with Blinky following close behind, and went to another tree where they had a good meal of young leaves and tender shoots”.

Thirty years ago, research on NSW’s North Coast established that there were three times as many koalas in young logging regrowth and plantations as in unlogged forest. Research at Eden found that koalas which had a choice between unlogged and heavily logged forest preferred the latter. Seed trees and edge trees in buffers and filter strips immediately flush with soft new shoots after logging, in response to increased light and moisture.

Since then, mild burning in forests has been reduced and trees are consequently declining. Eucalypt forests need gentle fire to recycle nutrients and maintain healthy soils and roots. Declining trees continuously resprout soft young growth until they eventually run out of resources. Koalas breed up in declining forests. When the trees die, koala experts call it “over-browsing”.

Three years ago, a study on the North Coast found that there are a lot more koalas than previously thought. They are now common right through the forests, irrespective of tenure or logging history: “Neither occupancy nor bellow rate are influenced by timber harvesting intensity, time since harvesting or local landscape extent of harvesting or old growth”.

Strangely, the authors of this study, Dr Brad Law et al, seem to have contradicted their own findings with the following statement: “Retention forestry has a significant role to play in mitigating harvesting impacts … but localised studies are needed to optimise prescriptions for koalas”.

NRC seemingly missed the apparent contradiction and gave the experts more money to research the phantom impacts on koalas of logging. This was the new research reported by NRC and welcomed by Timber NSW.

Typically, the Executive Summary doesn’t point to a final answer or solution. That would indeed be an unexpected research outcome. Instead, we’re informed that “more research is needed to improve our understanding of the immediate and direct impacts of intensive harvesting on koalas in north coast state forests”.

When I worked in forest research, our goals were to find solutions. These days, researchers look for problems and governments respond by throwing money at them. The NRC research has been a great waste of time and money. It is very disturbing that they haven’t recognised the clear scientific evidence of koalas irrupting in declining forests. It is even more troubling that their koala experts are apparently unable to see that the forests are sick.

Some “eminent scientific researchers” “selected” by NRC are supposedly studying the nutritional value of eucalypt leaves according to species and environmental variables. They don’t seem to comprehend that koalas are feasting on soft new growth in sick eucalypts from a multitude of species across a broad environmental spectrum. At the same time, the NRC is overseeing another million-dollar research program on what they call ‘eucalypt dieback’.

The eminent dieback experts apparently don’t understand that so-called: koala over-browsing; Bell Miner Associated Dieback; Snow Gum Dieback; Condamine Dieback; Monaro Dieback; New England Dieback; High Altitude Dieback; Regrowth Dieback and all the other varieties of chronic eucalypt decline with their weirdly inappropriate names, arise from lack of ecological maintenance by mild fire.

Some of the declines are exacerbated by pasture improvement, but that’s another story.

Dieback is a natural defence against acute environmental stress in healthy trees. Healthy forests maintained by mild burning quickly recover from natural stress when droughts break or floods recede.

On the other hand, koalas, possums, insects, mistletoes, root parasites and fungi irrupt in chronically declining trees within mismanaged forests, until trees and arbivores inevitably crash in droughts. But NRC uses our taxes to pay for advice from forest pathologists who have the story exactly back to front. They think the symptoms are the causes.

So, we have a great irony where one group of scientists puzzles about ‘over-browsing’ by a supposedly threatened species whilst another group looks for ways to control the other native species irrupting in the same forests for exactly the same reasons. To top it off, Commonwealth bureaucrats are proposing to list koalas as an endangered species because of the Black Summer megafires.

Koalas are currently increasing faster than ever, because virtually all joeys are surviving where they would normally die of malnutrition. The carrying capacity of forests for koalas is vastly increased by all the soft young growth after high intensity fires.

Truly endangered species are those which live on the ground, where their naturally diverse, grassy habitat is being choked out by explosive homogenous scrub growth in landscapes suffering from want of mild fire and repeated incineration by entirely preventable megafires. Our infamous extinctions of small mammals occurred mainly in arid zones where there were no forests, no logging and no clearing.

Here’s the alternative view from a registered charity subsidised by taxpayers: https://www.facebook.com/Bob.Brown.Foundation/posts/10159453709710928

NRC could do their job a lot better by working to restore mild burning instead of supporting self-serving research founded on green ideology.

Vic Jurkis is a former senior NSW Forestry Commission professional forester. In 2004 he was awarded a Fellowship by the Joseph William Gottstein Memorial Trust, to investigate eucalypt decline across Australia. He has published two books, Firestick Ecology, and The Great Koala Scam, both available from Connor Court.