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Catchments

As the Forestry Corporation now takes second place with regard to koala management. My comments on the OE&H’s koala strategy focused mostly on its ideas about koalas. In particular the paper titled “Extinction in Eden, identifying the role of climate change in the decline of the koala in south-eastern NSW” (Lunney et al, 2014).

While not doubting climate change has recently had a major negative impact on koala habitat. I do doubt the notion that climate change has played the major role in koala decline, particularly in this bio-region.

The research Lunney et al quote in support of the climate change theory, Lawler et al ( 1996), found either increased CO2 levels or reduced nutrient availability led to ” . . . lower leaf nitrogen concentrations, higher leaf specific weights and higher levels of both total phenolics and condensed tannins” in Forest red gum leaves

Hence, changes to soils that lead to a permanent decrease in nutrient and/or water availability, will have a negative impact on koalas. The problem within the OE&H is a belief that soils have not changed and are fairly consistent throughout NSW. So Lunney et al infer, because trees grow well in paddocks around Gunnadah, there’s no reason why they won’t do the same in the Bega Valley.

So it was interesting to read, in the Bega District news, that koalas around Gunnadah, where the population has dropped 50% since 2008, have taken to ” . . . drinking extensively from custom-made watering stations, even in autumn and winter.” According to Valentina Mella, from Sydney University’s school of life and environmental sciences. “My thought is that the leaves they’re eating are not providing enough moisture … because with climate change the chemical composition of the leaf changes. The leaves become tougher, they become drier, they have less nutrients and they even have more toxins. In the past decade there have been a lot of heatwaves and prolonged droughts, which have killed a lot of koalas. They literally drop out of trees.”

What Lunney et al neglect to mention is that fact that all the koalas on former primary habitat in this bio-region dropped dead over 110 years ago. Linking this decline with climate change seems to be drawing a long bow.

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Bega Shire Council has released the final Rapid Catchment Assessment reports for the Cuttagee, Middle and Nelson lake catchments. They are comprehensive documents that make many sensible and practical recommendations to address degraded areas, mostly on private land.

On public land, as indicated in the map a Cuttagee catchment above, many locations, in this case around 200, where found to be potential sources of water pollution. In addition, significant areas of ‘head-cut’ and gully erosion were identified. The sediment yield from ‘head-cut’ erosion areas alone is estimated to be more than 1000 cubic metres in all three catchments. Many of these locations have never been subject to integrated logging, but were trashed before woodchipping began.

The consultants Elgin Associates Pty Ltd, provide the following description and recommended action for the Nelson catchment :

” Multiple examples of active head-cut that have formed deep incised gullies. Natural erosion process that shows examples of undercutting, lateral bank erosion and slumping due to highly erodible, sodic soils. These may have been exacerbated by historical logging operations and past fire events in the forest. Difficult to treat due to scale of problem and site access. Majority of the sediment fractions eroded from the head-cut and gullies have been re-deposited downstream and may not reach the estuary. However, a proportion of dispersible fraction of sediment fines has and will continue to be delivered to the estuary back lagoon under high flow events. Recommend a collaborative research project with a university to further investigate the significance of the process – spatially and temporally, and identify factors that may be exacerbating the process, and what potential actions could be undertaken to halt or slow down process.”

While I did some include some management suggestions with my comments on the koala strategy. The starting point requires the NPWS/OE&H to firstly acknowledge the issues and learn more about the land they manage, so they can do something positive, for a change.

As reported in the Bega District News, a group of south coast oyster farmers recently met at Wapengo Lake. Clearly working to improve their Environmental Management System (EMS), the article referred to research, initiated by the farmers, into oyster growth rates in seven south coast catchments. The results found oysters in Wapengo Lake had the highest growth rates.

In addition, the research found different parts of the lake provided the best conditions for oyster growth, at different times of the year.

The EMS coordinator pointed out that oyster farms could be influenced by other land management practises, including cows in streams and unsealed roads and tracks. Graham Major, one of the Wapengo farmers said “ . . . We owe what we have here to the local landholders –  what happens on the land ends up working into the lake and that affects us greatly.”

I can attest to the work of the local land-care group, having joined them, now many years ago, to help plant trees and shrubs along Wapengo Creek. However, as indicated in the map below, much of Wapengo catchment was, until recently, State Forest. About 45% of the Wapengo is private land and most of the rest is now part of the Murrah Flora reserve.

Also indicated on the map is the most recent logging event in the catchment during 1994. Other larger areas in the south were logged in 1992 and 1993. Since that time and to the best of my knowledge, there has been no logging or deliberate burning in the forest. Although the last time the roads were graded was at least a decade ago.

 

wapengo-tenure1

 

 

The BDN also reported on recommendations from the Independent Prices and Regulatory Tribunal (IPART). Among other things the IPART draft report suggests rating oyster growers, for using land (?) below the high water mark.

Naturally, oyster growers are less than enthusiastic about the proposal.

It would appear, that in Wapengo at least, growers face significant changes to forest management practices, given proposals to introduce broad acre burning, allegedly to protect koalas.

So it’s interesting that Bega Valley Shire Council, the ultimate recipient of any rates extorted from the oyster growers, is also represented on the cabal, for want of a better word, proposing the broad acre burning and posing a threat to water quality.

It may be one of those ‘catch 22’ situations, growers who can afford to pay rates to council, do so with the knowledge that council is working to reduce water quality and oyster growth rates.

As reported on the Let Tanja Forest live facebook page, the OE&H survey team recently sighted a koala. This is the first sighting by the team/s since the flora reserve announcement.

Speaking later on ABC radio, observer Rob Summers indicated he’d been involved in tree species preference surveys since 1997. He now works as a contractor for the OE&H and is also one of the community representatives on the flora reserve committee.

While this level of involvement could, at least for some, raise some issues. It may not be as important as the bias that propels the surveys forward. As OE&H koala survey person, Chris Allen reaffirmed, in a recent video for a commercial tourist group, he believes koala numbers are increasing.

However, if that were the case and a lack of logging was the reason, surely koalas in the Southeast NP would not be extinct and there would be more local sightings.

He goes on to suggest management over the next ten years will be really important for koalas, seemingly confirming his general denial about threats that may prevent koalas lasting that long.

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On management issues, one of the works program priorities in the interim working plan for the reserves (Apppendix 4, 2) is ‘Habitat Restoration’. The idea is to “. . . Assess areas dominated by thick allocasuarina regrowth to determine habitat restoration options. Implement habitat restoration trials over a number of the sites. If successful these may be applied more broadly within the affected areas.”

There is no doubt the occurrence of black forest oak (Allocasuarina littoralis) has greatly increased over the past twenty years. The question is what sort of trials are being proposed and whether these will account for long term changes to soils.

Ideally, information from the recently released catchment management reports, would help inform management in that regard. As indicated in the graphic above, highlighting land degradation and probable poor regeneration, within the reserve in Cuttagee catchment.

The only issue would seem to be that while soil landscape mapping can be found in the reference list in both the interim reserve working plan and the catchment report. There appears to be no reference to soil landscape mapping in the main body of either document.

On a positive note, these omissions may confirm the EPA has an ongoing role in the koala issue, if only to keep logging going elsewhere.

Following the recent ‘south coast low’, former Prime Minister Malcolm Turnbull was reported saying ” . . . climate change is bringing about larger and more frequent storms.” However, he added that the ” . . . flooding across eastern Australia can’t be directly attributed to global warming.”

While I have some difficulty trying to separate any weather from climate change, if one were looking for evidence that the storm was larger than usual, the partial destruction of the Eden woodchip mill’s loading wharf is a good regional example. On this issue, the Eden Magnet reported a South East Region Conservation Alliance ‘twitter’ saying “ . . . Act of God wrecks the Eden chip mill jetty and loader. Nature is fighting back.”

Like Malcolm Turnbull, SERCA’s ‘act of God’ would also seem to exclude a direct connection with climate change.  Locally there were two moderate flood peaks in the Murrah river, some 15 hours apart. The photo below shows water receding from the front yard after the second peak. Even though most of the Murrah catchment is forested, the flood water is very dirty.

Indeed Bega Valley Shire Council has a ‘boil water before drinking’ alert for customers on the Brogo-Bermagui water supply. The dirty water in the Brogo dam comes almost exclusively from Wadbilliga National Park.flood

Historically, accepted sources of colloidal materials and suspended sediment have included stream bank erosion, gully incision, roads and logging, particularly when the latter is combined with fire.

What is yet to be considered or accounted for is die-back, in its various forms. Perhaps moving in that direction is a research report titled ‘Bell miner associated dieback: nutrient cycling and herbivore crown damage in Eucalyptus propinqua‘, published early this year.

In essence the research and apart from iron concentrations, couldn’t find a strong correlation between tree crown health and either, leaf nutrients, soils or under-storey, where lantana dominated. Interestingly, very few psyllids were found during the research, undertaken during a dry spell. Rather ” . . . caterpillars of the concealer moth appeared responsible for most defoliation observed during our study the question arises if there is an association between other defoliators and BMAD.”

As usual I have some uncertainties about the soil sampling and analysis. For example, the question of whether the soils are dispersible isn’t answered, although it would have provided a link to current forest management.

However, further research is proposed including ” . . .  BMAD-affected trees growing in a soil with significantly different water-holding capacity would be valuable for future analyses because of the possible association of topographic moisture with BMAD.”

This particular suggestion would seem to fit in with DPI research, using lidar and multi-spectral satellite imagery ‘to apply a modelling system that accurately maps the current, and potential, distribution of BMAD.’

For the south coast including the distribution of forests subject to extensive canopy die-back, associated with dry weather and drought, would be appropriate. Based on the possible association between topographic moisture, dead trees and dirty water.

In response to some of David Shoebridge’s questions, about funding for the new Flora reserves and what the $2.5 million from the Environmental trust will be spent on. The NSW government has provided the following two answers,

1. The total additional funding allocated to the new Flora Reserves is $110,000 per annum ($2015-16).
2. The $2.5 million grant is to be allocated for additional costs associated with providing the timber from alternative locations.

Whether the $110k reflects a portion of the 2015-16 financial year, or total funding per annum isn’t clear. Similarly what it’s to be spent on is yet to be revealed.

Where the $2.5 million goes is also unclear. While the only apparent additional costs would seem to be haulage, it is possible that logs may also need be sourced and bought from private forest owners.

Other questions will be answered in May.

bmadtrial
Back in the flora reserve, non funded on ground works are ready to begin, with a trial aimed at addressing forest decline. Starting with Bell-minor associated die-back, the trial won’t be following
the general recommendation for applying bio-char to agricultural lands, one tonne per hectare.

Rather ,an initial application of one cubic metre of bio-char per hectare will be trialled. This is about one third of a tonne per hectare.
As indicted in graphic (inset) most of the forest around its perimeter, at upper elevations, have the same dry forest ecosystem (brown bits . Lower in the catchment, areas subject to BMAD (red circle) and forests above them are wetter. The plan is to bury half a cubic metre, at points on a 4 metre grid (one litre of char per hole) and at a depth safe from fire. The remainder will spread on the ground over the rest of the area.

A similar approach is proposed for dry forest without BMAD but with a 5 metre grid, putting a little less in the ground.

Even after being inoculated, in this case with ‘aqua-vita’, the bio-char is quite alkaline, having a pH of 8.5. In theory its application may marginally increase the soil pH from the current 5.5 and lower. Should this occur it may help to counter, at least to some degree, the negative environmental impacts associated with soil dispersion, including BMAD.

Last Thursday, I dropped into the Council/OE&H drop in information session about Cuttagee catchment. It was soon apparent that the stated aim, to ‘ target environmental issues within the estuary and catchment’, had yet to progress beyond the estuary stage. On the basis that this progression may occur, I mentioned the extensive canopy die-back maps produced by Forestry for the catchment and region generally. Also Forestry’s observations that ” . . . In Bega Valley Shire, on the south coast of New South Wales, every near-coastal drainage system contains bellbird dieback.” (Jurskis and Turner, 2002)
The chap from Council suggested they could have brought along a map of the catchment. However, based on the information being employed, it would probably be similar to the 2010 Wapengo catchment plan map below. The Environmental Management System associated with the map, doesn’t mention die-back either.
Due to this arguably limited approach, confidence that major issues will be identified in any catchment plans may require an act of faith. Compounding the issue is the long term inability to acknowledge soil dispersion and its association with die-back.

wapengoems

Coincidently, some associated research on the vascular traits of eucalyptus has recently been published in Ecology Letters. Unlike other species, the research found eucalyptus trees ‘cannot quickly adjust the size of their water transport vessels to cope with variability in water supply’. This limitation makes them ‘vulnerable to extreme heatwaves’ and leads to the ‘risk of developing air bubbles in their vessels’.
If this outcome was linked with soil dispersion and the associated reduction in soil Water Holding Capacity, a reasonable person might consider trees turning brown and dropping dead, during quite short dry spells, a realistic outcome.
Of course when the forests are brown, the potential for a hot fire is very likely to increase. So it was interesting to read NSW emergency services minister David Elliott’s comments regarding the Rural Fire Service. In essence ” . . . that the service needed more qualified salaried people and that it wouldn’t be too long before he could do away with the Dad’s Army of the VFA.”
While the politics of the comment are complex, when it comes to quick fire suppression I’d rather place my faith in the Friends of Oolong proposal for night equipped air-cranes. Along with the Hercules fire fighting tankers, currently being trialled in NSW.

 

 

 

 

Early this month the Green’s David Shoebridge and Labour’s Penny Sharpe asked several forestry associated questions in NSW parliament. Included in the issues were koalas, the ‘Murrah Reserves’, their management and the following questions from Ms Sharpe.

(1) What steps is the Environment Protection Authority taking to ensure that the principles of Ecologically Sustainable Forest management are implemented in accordance with the Integrated Forestry Operating Approval, to redress Bell Miner Associated Dieback?,
(2) What actions have been taken to identify and map all affected and susceptible areas? (a) What is the timeframe in which this will happen

Answers to the questions aren’t due until April 13. However, next week Bega Shire Council and the OE&H will be holding ‘community drop-in sessions‘, providing progress on the Rapid Catchment Assessments for Cuttagee Lake, Nelsons and Middle Lagoons.

forests and koalas middle and nelsons

According to Council’s Coastal Management Officer, Kyran Crane “ . . . The aim of these assessments is to target environmental issues within the estuary and catchment and to suggest targeted actions to remediate these issues,”
Exactly what can be expected from the assessments is unclear, although it would be unacceptable if issues like BMAD or extensive canopy die-back across tenures, as in the graphic above, were not considered.
So it was interesting to read a letter from the South East Timber Association, concerned that turning State Forest into reserve may not help koalas. According to association president Stephen Pope ” . . . SETA will be taking great interest in what changes will be made to current reserve management systems to ensure long term survival of koalas on the NSW South Coast. ”
SETA can be assured that others also have an interest in management systems aimed at beginning to address the known threats to koalas.

Of course this proposed management will require funds and according to the latest Australia Institute report on native forest logging, current funding continues to prop up a doomed industry. So it seems reasonable that these funds could be diverted to more appropriate management.

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