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As reported in the Bega District News, this week the Forestry corporation and the OE&H released their long awaited final draft working plan, for the Murrah flora reserves.
According to the plan ” . . . The aim is that with the cessation of forestry and some specific management actions, koala recovery in the Murrah Flora Reserves and adjacent forest can be realised over time. This will be tested in the long term by monitoring and evaluation within an adaptive management framework.”

Regrettably, the OE&H’s adaptive management framework has some significant limitations. In particular the need to maintain the illusion, when prescriptions are followed, it regulates a sustainable logging industry. Hence the only referenced sentence on soils is ” . . . The steeper slopes are susceptible to erosion if disturbed (Tulau 1997).”

On forest condition the plan indicates ” . . . Mid storey structure and composition varies across the reserves, with a key management issue being the extent of black she-oak regrowth and other disturbance-generated tree and shrub species. These contribute to increased vertical fuel loads and prevent germination and regeneration of preferred koala species, particularly woollybutt.”

Another issue that could prevent the germination and regeneration of preferred koala species is soil loss and the associated reduction in soil fertility. For example, the harvesting plan for compartments 2080 and 2081, in Mumbulla SF and dated 11-8-1994, estimated an average of about 9.5 c/m of sawlogs and 85 tonnes of pulplogs per hectare would be removed in the operation. However, the estimated soil loss from the operation, only provided for cpt 2180, was 132.8 tonnes per hectare.


I recently revisited the vast area burned in the Cuttagee catchment, to get some shots of brown and dry vertical fuel loads, now some months after the fire. Coincidentally, I came across two of the recently established research plots. As indicated in the photo above, this one is on relatively flat ground. Some silvertop-ash and all the black she-oak have been cut down and placed into piles. Retained trees are mostly silertop-ash, a couple of spindly stringy-barks and a hickory wattle.Walking around the plot it was clear that all of the silver-top ash have coppiced, with multiple stems growing from the stumps. In addition there are dozens of hickory wattle seedlings in the plot. Both of these outcomes will increase vertical fuel loads, although unlike forest around the plot, these fuel loads won’t be brown and dry.

In the second plot below, on a steep slope, three large woollybuts have been retained  during logging and it appears all of the regrowth trees were black-oak. These have been cut down and placed as one would make a bonfire. It appears attempts were made to burn the bonfire, although the timber was clearly too wet to burn. Hickory wattle seedling were also evident in this plot, although there were fewer than the first plot, perhaps due to erosion of the exposed soils. 

Forestry and the OE&H are accepting comments on the plan until January 31, 2018.

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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.

Now some months after the National Koala Conference, I happened to come across the OE&H’s power point presentation titled “Koalas, Fire Management & Habitat Rehabilitation in SE NSW”.  Not surprisingly for coastal koalas the two issues referred to are fire and getting preferred feed trees to germinate and grow.

The issue with fire was the Strategic Fire Advantage Zones (SFAZ) because they overlapped with areas occupied by koalas. The solution is to burn around known koalas and greatly increase the areas to be burned. Despite this approach the OE&H suggest there is room for the population to expand.

On the feed tree issue, some 28 locations have been chosen to trial regeneration techniques, as indicated in the table below.The treatment referred to as pruning appears to involve cutting down all the forest oaks and laying them across the slope. The approach would seem to confirm the OE&H is repeating the mistakes made trying to grow primary feed trees. In particular, a belief that the reduction of soil pH and associated decline in soil fertility, plays no part in tree germination, growth or koala survival.

The story is quite different in the northern hemisphere, where forest managers are concerned acid rain, in addition to logging has had similar negative impacts on forests. The USDA Forest Service for example, supports the Hubbard Brook Ecosystem Study in New Hampshire. One of the experiments involved a helicopter dropping 40 tons of wollastonite, a naturally occurring calcium silicate, onto a small ‘watershed’.

The outcomes have been very positive and arguably well worth a try in Australia, when forest managers are required to consider and act on science.

 

The NSW Department of Primary Industries has recently released a report titled  ‘North Coast Residues -A project undertaken as part of the 2023 North Coast Forestry Project ‘. The executive summary indicates ” The main purpose of this project was to determine the potential availability of forestry residues for bioenergy generation and other applications on the North Coast of NSW . . ”

With regard to residues from public native forests the authors suggest ” . . .The values assume that a substantial proportion of the biomass (typically at least 20% of the total biomass) is left in the forest after harvest. ” The DPI then provide estimated volumes of residue that are, in all cases, greater than 200% of the biomass removed during harvest.

There is also a section titled ‘Extraction of biomass for bioenergy from NSW North Coast regrowth native forests: impacts on nutrient availability’. Regrettably the authors indicate ” . . . However, this study does not constitute a full nutrient budget that would also take into account temporal and below-ground conversion dynamics, and natural nutrient inputs (e.g. via rainfall). ”

Such a short fall essentially renders the generally repetitious information useless. This is particularly the case given the proportions of nutrients found in leaves, bark, branches and wood are not considered in terms of the actual volumes exported from forests during logging. In addition four of the references are not to be found and the only reference to calcium (Marschner, H. 1986. Mineral nutrition in higher plants. Academic Press London), is unlikely to apply to the north coast or Australian forests generally. On a positive note the authors suggest a move away from post logging burns, so some of the nutrients can be retained.

Also on a positive note is the news that Friends of Leadbeaters possums have stopped logging 34 forests in the Victorian central highlands. The Federal court’s decision, on whether the EPBC act should apply to logging nationally endangered species habitat, may have implications for all Regional Forest Agreement areas.

As reported in the Bega District News this week, a koala was sighted early in the morning and captured on video, as it ran down the Tathra-Bermagui road. The observer, Michael Clarke, stopped his truck and took the video as the critter scrambled up an embankment and climbed the nearest small tree, a black forest oak. While Mr Clarke’s sighting made his day, describing the experience as ‘awesome’, he also expressed concern about the threat posed by foxes and suggested corridors to ‘allow safe travel across roads’.

ABC radio interviewed the NPWS’s Chris Allen who thought the animal could be a male, but appeared to be young and healthy. Lucky for it, because the last koala found on this road was a bit groggy, taken to a vet and subsequently released kilometers from where it was found.

What Allen didn’t mention was the potential that this young koala has been kicked out of its mothers home-range and is looking for somewhere suitable to live. The issue being, unless an older animal has died, finding somewhere suitable may be difficult. Mr Allen did mention the koala surveys have been ongoing for ten years, but nothing about publicly releasing any results. This lack of accountability seems to contrast with his frequently repeated talk about how important these koalas are.

However, one of the reasons for the lack of information could relate to the proposed roll-over of the Regional Forest Agreements. One outcome from the flora reserve decision being the increased uncertainty about timber supplies and the data required to reduce this uncertainty.

The map below provides the locations of timber inventory plots (red dots) undertaken on a regularised  grid for the Southern RFA  and locations of the first koala plots (light green dots), in the Eden RFA region. Those of greatest interest are on the Murrah Soil landscape (orange). Clearly re-measuring the plots in the Southern region would provide more certainty about timber supplies. Similarly, the release of data from the second round of federally funded koala surveys in the Eden region, would be desirable.


While the chances of either the state or federal governments releasing these data may be low. It would seem sensible for the conservation movement to demand both the release of the second koala survey data and data from the re-measurement of the Southern timber inventory plots.

While the major issue is what grows back after logging and the RFAs are supposed to be based on the National Forest Policy Statement. Among several interesting research articles, recently published in Functional Ecology, is one titled ‘Rewilded mammal assemblages reveal the missing ecological functions of granivores’. Previous arid land research, undertaken where most of the mammals were functionally extinct, had concluded ants were the major predator of plant seeds.

However, this recent research was undertaken in fenced areas, at Scotia wildlife sanctuary and the Arid recovery reserve, where native animals have been re-introduced. In brief the researchers found animals are the major seed predators and “. . . hypothesize that the loss of omnivorous mammals may be a factor that has facilitated shrub encroachment in arid Australia.”

Coastal forests are facing a similar situation and the increasing proportion of non-eucalyptus trees, like black forest oak, may reflect the loss of species critical for forest health. While these matters may not rate highly in the NSW government, it would be unfair to accuse organisations like the NPWS of doing nothing. Regrettably, the new road signs in the photo below suggest an odd set of priorities and doing nothing would have been cheaper.

 

 

Spring has definitely sprung, although 30 degrees with a strong north-westerly wind does seem more consistent with an early summer. Perhaps more important is that this month, the eleventh day to be precise, is supposed to end to the six year regional federal and state funded koala projects.

Regrettably, there are still no reports for the ‘Foundations for River Recovery and Return of Koalas to the Bega Valley‘ project. Similarly there is still only one ,arguably irrelevant report for ‘Corridors and core habitat for koalas on the NSW Far South Coast’ project.

Of course time moves on and now, with the conservation movement calling for adaptive management, a reasonable question could ask about the degree to which our understanding of koalas and their habitat, has improved during this time. In addition, whether a similar sum ($13 million)could provide for more positive outcomes, given what has been learned.

 

The map above comes from the original for ‘Corridors and core habitat for koalas on the NSW Far South Coast’ project application.  It shows the areas defined as ‘core koala habitat’, aka logging exclusion areas. Areas proposed for revegetation with primary koala feed trees and theoretical corridors. Added to the map is the orange ellipse, indicating core habitat, recently burned.

One of the NSW government’s concerns was that a previously federally funded koala project, in an area it proposed for revegetation, had planted the trees incorrectly. Hence it had to be done again.
This suggestion forms the basis for the the NSW government’s general understanding of the environment. In essence that soil fertility never reduces, irrespective of how the land is managed. Of course this position may have changed since 2011, but to date, there is no evidence to prove it.

Hearing news of the alleged illegal interstate waste dumping, aired on Four Corners last Monday, was a bit of a blast from the past. As it transpired the EPA’s director of waste management, Steve Beaman, was one of the first EPA employees I encountered back in the early 1990’s.

At the time the issue was logging in the Murrah catchment and concerns about the adequacy of what was then Forestry’s Environment Pollution Licence. One of the concerns was soil erosion and how the volume (tonnes) of soil lost after logging was being calculated.

Forestry relied on the broad map of geology, reproduced below, but a bit blurry. However the geology in the ellipse, where four compartments were being logged, wasn’t consistent with the map. After visiting the site and taking samples, Steve Beaman agreed the geology was not consistent with the leucogranite and sandstone indicated on the map.

However, Mr Beaman couldn’t say what sort of rocks they were because he had never seen them before. In one of these compartments, after the first large rainfall event, the majority of soil disappeared, leaving behind a course grained white quartz.

It was a couple of years after this that the EPA dropped the geology thing and allowed forestry to determine if soils were dispersible, rather than use the published soils data.
While one trusts the Independent Commission Against Corruption puts an end to the waste rort, the land degradation and pollution from logging is arguably just as corrupt. Two of the compartments, including the white one, were later put into Biamanga National Park.

Arguably the greatest advance in feral animal control over recent times has been the feral cat grooming trap or ‘felixer’. According the the information brochure “. . . Feral cats are the greatest threat to native wildlife in Australia. They have been implicated in at least 27 mammal extinctions across Australia and currently threaten more than 100 native species, including mammals, lizards and ground nesting birds. ”

To address this situation ” . . . The Ecological Horizons grooming trap uses sensors to detect the presence of a feral cat and sprays a lethal dose of toxic gel onto its fur from up to 4 metres away as it is walking past. The feral cat instinctively grooms the gel and in doing so ingests the lethal dose of the poison and dies.”

While looking forward to the deployment of these units at a bio-regional scale, the technology may have other useful applications. In particular closing a gate when a cat or fox is detected.
Such a device would enable one or more entrances in a fence to be kept open, for much of the time. Hence other species like kangaroos and wallabies could get into and out of fenced areas. The same applies to reintroduced species, should they breed up.

Early next month the Port Macquarie Koala Hospital will be hosting the second national koala conference. Among the 30 or so speakers at the conference is OE&H employee Chris Allen, giving a talk titled ‘Fire & habitat rehabilitation in the SE forests of NSW’.

While I expect the talk will focus on the OE&H’s claims it is protecting koalas from fire and planting trees on cleared land will help them. I also expect there will be no disagreement with these claims. On the fire issue, it is now a few weeks since the first burn was ignited in the Cuttagee catchment. During that time the scorched leaves on eucalyptus have turned brown as indicated below.


Also during this time the scorched needles on forest oaks have fully cured and also turned brown. Apart from some remaining large trees with black trunks, the whole area is now brown.

Prior to the fire, 30 years of litter, mostly from the oaks, provided soil cover that formed a thick mat, partially welded together through the actions of various fungi. Post the fire, the greatly reduced litter layer will be dry and loose. Coupled with the dead oaks, the outcome, come next summer, would seem to be ideal conditions for a rapidly moving wildfire.

Added to all this, yesterday and last night we received 100mm of rain, a large proportion of which was high intensity rainfall. While this issue could be taken up with local government, getting the OE&H to be a bit more accountable would help.

Sometime in the not too distant past, OE&H supporter the South East Region Conservation Alliance announced that its website will not be updated. No reasons are provided, but it’s safe to say that SERCA has not been an effective agent for change.

So it was interesting to receive the message below, recently posted on a local mailing list.

———————————————————————–
In 2019 the Regional Forest Agreement (RFA), which underpins the native forest industry in our region, expires. We understand that government preference is for an automatic rollover with no public consultation. We consider this to be unacceptable.
On Sunday June 11 at the Tathra hall, we will be holding a forest forum which is an initial step in promoting the message that there are better uses for our native forests than woodchipping. Local environmentalists have been developing alternative forest strategies and the time has come for wider community involvement.
You will receive a more detailed notice of June 11 proceedings closer to the day. In the meantime, we ask that you flag the date and mention it to friends.
David Gallan
Tim Taysom
President Vice-President
National Parks Association (Far South Coast Branch)

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