Lessons from Lanark
Landholders Institute
For sustainable production, For sustainable conservation,
And defending Landholders rights
Convenor Leon Ashby, 3 Hay Tce, Kongorong SA 5291, ph 0887389313
email barcoorah@mail.com
Web site http://landholders.tripod.com click here for News & views archives
The following article is about the implications of a 40 year study of birds on a victorian property "Lanark" .
From 1967 to 1997 the property was revegetated from 0.3 per cent tree cover to 11 per cent. The birds returned from 39 species to 155 species and it is believed that when trees develope hollows within the next 140 years all bird species will again be present. This study has implications for all vegetation management group across Australia.
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The Real Lessons of Lanark.
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Ian Mott casts a farmer's eye over an analysis of vegetation/wetland cover and bird recolonisation on a 800 hectare property that had been fully cleared for a century in the vegetationally challenged Western District of Victoria. And he comes to a few conclusions that appear to have escaped the land management bureaucrats.
The story of Lanark has a very impressive list of boosters. Graeme O'Neill's, Renaissance on Lanark 1, has the endorsement of Birds Australia, The Natural Heritage Trust, Bushcare, Landcare Victoria, the Victorian Department of Natural Resources and Environment and the Norman Wettenhall Foundation. There is an equally impressive list of acknowledged advisers and contributors to the Lanark experiment.
My copy came from the Parliamentary Office of Dr David Kemp, the Federal Minister for Environment & Heritage. And the message is unambiguously positive, proudly proclaiming the successful "transformation of a once ravaged sheep property", into "an environment in irrepressible good health", on this "grazing property like no other in Victoria" 2.
And there is no doubting the veracity of these descriptions of the Fenton family's achievements for they are based on 45 years of "meticulous monitoring of the property's bird fauna and chronicled perhaps the greatest of Lanark's miracles: the renaissance of almost the entire suite of bird species that inhabited the region's native woodlands and wetlands more than a century ago" 3.
In all, 155 resident or itinerant bird species have been recorded compared to only 39 species in 1956 and about 157 species in 1850. According to Dr Geoff Barrett, Co-ordinator of Birds Australia's nationwide Birds on Farms project, the property is "a model for a more enlightened era of farm management in Australia. And, "Since birds occur close to the top of the food chain, they are good indicators of the health of the environment" 4.
The 1963 late summer aerial photo is of a harsh brown landscape, "Typical of most Western district properties, its empty paddocks rolled to the horizon, unbroken except for a few Radiata Pines and Sugar Gums" 5. It is a stark contrast with the 1992 photo of the new wetlands at high water, shelter belts and forestry plantations, "intrinsically linked to create a more ecologically and agriculturally sustainable system overall" 6.
The charts by Elizabeth Jacka (page xi to xiv) and the back page bird list impressively illustrate the extent of the original abundance, the consequences of a century of denudation and the steady recovery of birds and all their associated ecological values.
And there is no disputing O'Neill's conclusions that, "Today the Fenton's farm and it's production systems seem well insulated against environmental adversity - drought, salinity, water contamination, algal blooms, lethal temperature extremes, insect pests and disease" 7.
It was no doubt for this reason that "Lanark was the first working family farm selected as a release site in a captive breeding program for Victoria's most endangered mammal, the Eastern Barred Bandicoot" 8. An initial release of ten animals in 1994 has grown to at least 50 with the help of the dense shrub cover and fox and cat controls.
But what does all this really prove?
1. Lanark has proven that the orginal clearing and the ecological declines caused by a hundred years of fully cleared agriculture do not constitute irreparable environmental harm. While the Fentons may have taken 30 years from 1967 to 1996 to carry out their restoration of ecological values, some very significant results can be achieved in much less time.
2 Lanark has proven that a fully functioning set of wetland and woodland ecosystems can be restored to a seriously degraded landscape with only about 3% wetland, 11% woodland and the balance as grassland or other agricultural uses. The analysis in Fig 1 reveals that by 1976, ie within a decade of serious effort;
(a) most of the wet grassland species had remained on site in 1956 despite the complete absence of woodland and wetland vegetation.
(b) some 79% of woodland species had returned even though the woodland cover was only 1.9% of the property.
(c) the woodland that achieved this result was almost entirely exotic, Pinus radiata.
(d) some 86.5% of wetland species had returned when wetland cover was only 2.7% and vegetation buffers were either very immature or non-existent.
(e) this level of recovery was achieved by small unconnected vegetation clumps that were separated by pasture gaps as wide as 700 metres.
(f) given the dearth of vegetation in the surrounding district of 3500ha, the recolonising species would have crossed gaps of 1 to 2 kilometres to find their new habitat.
By 1996 the almost complete recovery of all species was achieved by;
(g) fragmented vegetation pockets that are still predominantly exotic but with native shrubs adjacent to them. These pockets do not qualify as native remnant vegetation.
(h) vegetation pockets that are significantly smaller than the widely recommended minimum clump size of 5 hectares.
(i) vegetation pockets that are separated by pastured gaps as wide as 400 metres.
(j) wetland buffers that are only connected by water, with a number of gaps of grazed pasture to the waterline.
(k) a corresponding natural recolonisation by all the insect species on which the birds depend.
3 Lanark clearly demonstrates that there is no such thing as a "Local Extinction". There are only localised periodic absences of species whose return is contingent on the landholder perceiving policy settings as being consistent with his management intent.
4 If these thresholds of non-remnant vegetation are sufficient for the restoration of ecological values to a fully cleared landscape then the same thresholds of existing native remnant vegetation, or non-remnant regrowth, would be more than sufficient to maintain ecological values in a cleared landscape.
5 The common assumption in vegetation management policy that adequate connectivity is synonymous with connected canopy has no valid basis. And one must distinguish between the smaller gaps that species would prefer not to cross when on routine tasks like feeding and watering and the larger gaps that species will clearly cross for mating purposes or in search of a new territory. As with humans, all species will travel considerable distances to get laid but would rather have breakfast in bed.
6 On the basis of the evidence from Lanark, one can reasonably assume that any appropriate vegetation cluster (including a single tree, post or pole) that is capable of providing roost, rest or vantage point, whether native or exotic, whether of timber, orchard or shrub, within 400 metres of another such cluster, is adequately connected for all routine bird activities.
7 On the basis of the evidence from Lanark, one can reasonably assume that any appropriate vegetation cluster, of the type mentioned in 5 above, within a kilometre of another such cluster, is adequately connected for mating and migratory purposes, ie., for maintaining biodiversity.
8 The prevailing departmental/green view, as outlined in the following quote, from Thorburn, Gordon & McIntyre 9, is bunkum.
"The rationale for applying this 30% threshold at the property scale is that the actual distances that mobile organisms (notably birds) can move in non-habitat are in the order of 10's or 100's of metres rather than kilometres. This means that vegetation retention within properties is important unless local extinctions are an acceptable part of a biodiversity plan."
This statement clearly implies that all non-remnant vegetation is non-habitat and that birds have a very limited ability to even fly over, let alone utilise, pasture or other forms of so-called non-habitat. But Lanark confirms the bleeding obvious, that the spaces between the trees are just as important as the trees themselves in defining habitat.
Natural woodlands rarely exhibit uniform spacing between trees and the confirmation of a minimum gap distance of 400 metres suggests that most relevant species are capable of fully utilising grassland resources out to at least half that distance, ie., out to 200 metres.
9 Edge effects, for most woodland species, are mostly beneficial. It can be reasonably assumed that the habitat that is denoted by any tree includes all grassland within a 200 metre radius. Consequently, a single line of remnant woodland species would be capable of delivering most of the bio-diversity values provided by a 400 metre wide corridor of the same remnant woodland.
10 The Lanark data does not indicate how much of the increase in bird numbers after 1976 would have taken place without any additional tree cover. Most of the 1976 tree cover was less than 10 years old with a higher proportion of radiata. Many native species would not have been flowering yet. It may well be the case that the full suite of woodland species could have been achieved with only 5% cover (and larger gaps) but with more natives and older specimens.
11 The broader issue of adequate connectivity for non-bird species is not addressed by the Lanark research. But clearly, in the absence of a paved motorway, most larger terrestrial fauna, from wallabies to goannas, are perfectly capable of crossing similar gaps. For the smaller species, a tree canopy is irrelevant as their primary shelter is provided by understorey grasses and shrubs. So the pasture and a range of crops and orchard activities within the gap itself, can provide adequate connectivity for mating and migratory purposes.
12 Wetlands are far less fragile than we have been led to believe and are far more capable of recovery and restoration than we have been led to believe. They can obviously perform their ecological functions in association with grazing and need not be completely surrounded by vegetated buffers.
13 A number of birds that prefer nesting hollows were still able to use the habitat as a food source despite the absence of suitably deformed local trees. The absence of nest sites has reduced their presence but has not precluded them as an ecological value. O'Neill states that nesting boxes are a poor substitute 10 but has been too intellectually lazy to compare the immediate and continuing results of all artificial nesting options with the glaring non-result produced by passively waiting 140 years for the existing trees to develop suitable hollows.
Implications for vegetation management policy.
Lanark highlights the appalling inconsistencies in the officially sanctioned view on vegetation management. On one hand a who's who of ecology is loudly proclaiming a Victorian farmer as a hero for fully restoring ecological values with 11% coverage by non-remnant vegetation. While on the other, an entire government, from Premier Beattie down, is predicting ecological armageddon if Queensland farmers bring their existing native remnant cover below 30% of their property.
And this hypocrisy is made all the worse by the fact that the majority of the vegetation that is now subject to the clearing controls is not old growth. The aerial photos of the 1940's and 50's prove that, like the Fenton's, their forest has actually been re-established on previously cleared land. For obvious reasons, early tropical farmers better understood the importance of shade trees than their southern counterparts. And this retained mosaic, combined with the summer tropical rains, meant that there was no need to actually plant trees because the native seedlings were able to survive and dominate the paddocks.
The tropical farmer's problem is pasture maintenance in the face of too much regrowth. And if the farmer got a bit behind in this pasture maintenance, or if he decided to bring on a new generation of shade or timber trees, then the regrowth could grow to more than 70% of the original canopy height. It is then automatically reclassified as remnant without any regard for the farmer's management intention.
Through ill-conceived and shoddily drafted clearing controls, the primary instruments for restoring and maintaining the ecological integrity of farmland (trees) have been converted into an instrument for rationing all development. In so doing, governments have betrayed the most fundamental attribute of an effective rationing system. That is, that we all share the burden or shortage equally.
If all the trees are already gone then the full range of future development options are available to the landowner to fully participate in the 21st century. But the farmers who have purposely managed their grazing land to fluctuate between 10% and 60% forest cover, and outperformed the Fenton's by miles, get neither credit nor reward for their achievements.
They are condemned to watch, uncompensated, as everyone else pockets their untaxed capital gains. Over the past 12 months Urban Australia has enjoyed household capital gains of over $300 billion but as most of this is owner occupied, it will not be subject to capital gains tax while farmers are only CGT exempt for the house paddock.
The burden of proof now rests squarely with the proponents of property level 30% vegetation retention targets to provide detailed, verifiable and specific evidence that will support their case. The days when a farmer will accept a bureaucrats word on face value are finished.
It is also clear that adequate connectivity for the maintenance of biodiversity values can be achieved across gaps in native vegetation cover. One can no longer assume that the removal of native trees from a corridor will sever the connective value of that corridor.
It also follows, from point 9 above, that any area of farmland that comprises of remnant associations in alleyways separated by distances less than 400 metres must be classified as fully functioning examples of that ecosystem for regional vegetation management purposes. It also follows, that the basal area within alleyways must be compared with the natural firestick farming basal area for catchment management purposes.
Indeed, for any representation of a habitat to be regarded as a "true and fair" representation, it must indicate the adjacent areas over which, say, 80%, 60%, 40% and 20% of resident species are likely to range over. The listing of small vegetation clumps as habitat for species, like the Black Cockatoo, that has a home range of up to 100,000 hectares, is highly misleading and often fraudulently so.
The research on the capacity of non-remnant vegetation like exotic plantations, orchard trees, crops, shrubs, pasture and even weeds, to contribute to maintaining viable networks has been well summarised and thoroughly referenced by Tim Low 11, and must be assessed by regional and local vegetation planning processes.
This contribution of non-remnant vegetation, and the capacity for biodiversity to be not only maintained but also restored in a fragmented, anthropogenic landscape, are most certainly relevant considerations under Section 23 of the Qld Judicial Review Act 12 and relevant National and other state legislation. They must be taken into account in planning decisions.
References
1 O'Neill, G. "Renaissance on Lanark", Supplement to Wingspan, vol 9, no 1, March 1999, Birds Australia.
2 Op. Cit. p2.
3 Op. Cit. p5
4 Op. Cit. p6
5 Op. Cit. p4
6 Op. Cit. p2
7 Op. Cit. p9
8 Op. Cit. p15
9 Thorburn, P.J, Gordon, I J, & McIntyre, S, "Soil and Water Salinity in Queensland: The prospect of Ecological Sustainability Through the Implementation of Land Clearing Policy", The Rangelands Journal, Vol 24 (1), 2002.
10 O'Neill, G. Op. Cit. p12.
11 Low, Tim. The New Nature, winners and losers in wild Australia, 2002. Penguin.
12 Judicial Review Act 1991 www.qld.gov.au/legislation See also, Commonwealth Administrative Decisions (Judicial Review) Act 1977, Section 5. At www.austlii.edu.au/au/legis/cth/consol_act/
Background.
In the 1920's the Mott family were compelled by government policy to clear and burn 120,000 tonnes of high quality timber from their property in Northern NSW. Today this resource would be worth about $35 million but then it was worthless due to the market glut caused by compulsory clearing. By the 1940's they began planting wind breaks of native timbers, collecting and germinating their own seedlings as native stocks were not available. This, combined with assisted natural regeneration has restored the original wet sclerophyll mosaic to 80% of the property. Ian Mott (3rd Generation) is a Fellow of the Landholders Institute and President of the Regrowth Foresters Association.
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