No koala crisis – forester claims

Following up on his book ‘Firestick Ecology’, former forester Vic Jurskis has written a paper, accepted for publication in Wildlife Research, titled ‘Ecological history of the koala and implications for management.’

According to Mr Jurskis, the decline in koala populations is not a crisis, rather koala numbers are returning to a pre-European state. The ‘eruptions’ in koala numbers, here 120 years ago and those of translocated island koalas in Victoria, is put down to poor management, particularly a lack of frequent burning.

In one press report he describes the creation of the Murrah Flora reserve as a perverse outcome for a species that was not recorded in the area at the time of European settlement. Exactly how he knows this and how this theory fits with his previous estimate of 800 to 1600 koalas in the Eden region isn’t clear.

I do recall the first time I met Vic, back in the 1990’s, not long after the 8 radio collared koalas had died. I informed him of koala pellets I located in Nullica State Forest, where two of the aforementioned koalas were tracked. His response was to say the two koalas, Robert and Roberta, were the only koalas in Nullica SF.

Vic’s simple theories have many holes, not least of these is the knowledge that the primary feed trees behind the ‘koala eruption’ in the Eden region are now endangered, because they don’t grow back. The evidence indicates secondary koala feed species are in the same boat.

So while I do agree with Vic, that forests need better management, that’s where the agreement ends. It is simply not possible to undertake low intensity burns in these forests, due to the previous and ongoing poor management.


However, I believe management aimed at reducing fuel loads would create employment, while providing some protection from wildfires and aid in funding real attempts to restore biodiversity. The photo shows the first of nine 10×10 metre plots, logged and burned in 1982, where the majority of forest oak have been removed. Apart from two retained trees, a Yellow stringy-bark and a Rough barked apple at the rear of the plot, only one very small and sick apple has regenerated in the plot.

The small dead trees in the plots, oak and silver-top ash, have mostly been converted to biochar, producing just over 500 litres or enough to spread half a litre per square metre. When the green wood dries, I’ll add another 50 litres to each plot.  In the bare areas I’ve begun planting Woollybutt seedlings and Yellow stringy- bark seed.

Unlike the OE&H’s approach, in the square metre around these plantings, I’m incorporating 350 grams of either dolomite or crushed sea-shells, with another litre of char and in some instances 250 grams of gypsum, into the first couple of inches of soil.

While there is uncertainty about whether they will grow, if they do it will be interesting to compare outcomes with the OE&H’s soils haven’t changed approach.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: