Identification, Assessment and Protection of National Estate Part a natural Values


Flora and fauna with disjunct populations



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4.2 Flora and fauna with disjunct populations


Disjunct populations are those that have become physically separated, resulting in minimal or no gene flow between them. This separation could be caused by a break in a formerly continuous distribution or by long-distance dispersal (jump dispersal) over a barrier. Heatwole (1987) summarised features that could act as barriers including climate, topography, vegetation type and intra or inter-species competition. In North-Eastern NSW, the deeply incised topography, diversity of species, geology, altitudinal range and topography and the movement of tall forests across the Pleistocene landscape in response to climate change are all conducive to the development of disjunct populations (Covacevich 1991, Osborne 1991). Often, a disjunction takes the form of a larger parent or core population and a smaller outlier, or outliers, but in some instances, the disjunct populations are of about the same size. Species with disjunct populations can be regarded as being important elements in the evolution of Australian flora and fauna (Sub-criterion A1).
Disjunct species in Upper North-Eastern NSW were taken to be species with highly specific habitat preferences and low powers of dispersal such as frogs and reptiles, species with documented isolated populations within the region, and associated with fragmented habitat, primarily rainforest.

4.2.1 Method

For fauna, workshops were used to identify fauna species with disjunct distributions to provide a species list. Data was derived from surveys conducted for the comprehensive regional assessment and from the NSW NPWS wildlife atlas. 92 fauna species were identified as having disjunct distributions. Literature reviews were also carried out to supplement the workshop responses. For flora, the literature review conducted as part of the flora workshop was used to provide a species list. Data was derived from the validated flora data-set used for comprehensive regional assessments. 227 flora species were identified as having disjunct distributions.


Point location information for all identified species was plotted respectively for flora and fauna on a one kilometre square grid. An analysis was done which then searched for records of disjunct species within a two kilometre radius around each grid cell. The resultant analysis showed concentrations of disjunct species, for flora and fauna respectively, across the landscape.

4.2.2 Establishing the threshold

The above information was displayed as standard deviations above the mean number of species in the landscape. Two standard deviations above the mean number of species for both flora and fauna was taken to be above threshold.



4.2.3 Results

The areas identified as having indicative national estate significance for species with disjunct populations are delineated on Map 7 for fauna and Map 8 for flora. Areas shown represent concentrations of species with disjunct ranges using relevant best available information to the lower north east comprehensive regional assessment. All areas identified are significant concerning Australia’s evolutionary history and are above the threshold warranted for national estate listing.


Some of the major areas delineated for species with disjunct populations were the rim of the Dorrigo plateau, running around the Macleay valley river gorges to Werrikimbee National Park for both flora and fauna. Additional concentrations were identified in Doyles River and Bulga State Forests (for fauna), Barrington Tops (for fauna and flora), and the area around Olney and Ourimbah State Forests (for fauna). On the coast, sites were found around Port Stephens for flora and fauna, Craven State Forest (for fauna), Booti Booti National Park (for fauna), Crowdy Bay National Park (for flora and fauna), Lake Innes Nature Reserve (for flora and fauna) and Limeburners Creek Nature Reserve (for flora and fauna).
323,900 ha were identified as above threshold for fauna with disjunct ranges. Nearly 21% of this was on existing reserves and 43% in state forest. 178,700 ha were identified above threshold for flora with disjunct ranges. Nearly 49% of this was on existing reserves and 28% in State Forest (Table 9). Places already listed on the Register of the National Estate were strongly associated with the areas delineated as having values associated with species that have disjunct distribution. The south-west extension of Oxley Wild Rivers National Park is the only major listed site that did not having values contained within it.
TABLE 9: Land Tenure of indicative national estate species with disjunct ranges


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

For Fauna

For Flora


68,700


87,100

21%


49%

State Forest

For Fauna

For Flora

139,400


50,100

43%


28%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


4.3 Flora and Fauna at the end of their distribution range


Flora and fauna species at the end of their range are those species whose known distribution range terminates within or near the RFA region. The value can reflect broad biogeographic boundaries or past species population movements. Within the context of north-eastern NSW, species at the limit of their range tend to be those species from tropical or sub-tropical Australia whose southern distribution limit occurs in the region, or those species from temperate Australia who reach their northern distribution range limit in the region. There are also some inland species whose distribution extends down onto the coastal plain through the Hunter Valley. Distributions and range limits can yield important information relating to past population movements and evolutionary history and species at the end of their range are importance in the evolution of Australian fauna and flora (Sub-criterion A1).

4.3.1 Method

For fauna, workshops were used to identify fauna and flora species that reach the limit of their range within the region. Literature reviews were also carried out to supplement the workshop responses. Data was derived from surveys conducted for the comprehensive regional assessment, from literature reviews and from the NSW NPWS wildlife atlas. 180 fauna species and 998 flora species were identified as reaching their distribution limit within or in close proximity to the RFA region.


Point location information for all identified species was plotted respectively for flora and fauna on a one kilometre square grid. An analysis was done which then searched for all records within a two kilometre radius around each grid cell. The resultant analysis showed concentrations of species at the limit of their range for fauna and flora respectively, across the landscape.

4.3.2 Establishing the threshold

The above information was displayed as standard deviations above the mean number of species in the landscape. Two standard deviations above the mean number of species for both flora and fauna was taken to be above threshold.



4.3.3 Results

The areas identified as having indicative national estate significance for species at the limit of their range are delineated on Map 9 for fauna and Map 10 for flora. Areas shown represent concentrations of species at the end of their range using best information available to the lower north-east comprehensive regional assessment. All areas identified are significant concerning Australia’s evolutionary history and are above the threshold warranted for national estate listing.


Some of the major areas delineated for species with disjunct populations were the rim of the Dorrigo plateau, running around the Macleay valley river gorges to Werrikimbee National Park for both flora and fauna. Additional concentrations were identified in Doyles River and Bulga State Forests (for fauna), Barrington Tops (for fauna and flora), and the area around Olney and Ourimbah State Forests (for fauna). On the coast, sites were found around Port Stephens for flora and fauna, Craven State Forest (for fauna), Booti Booti National Park (for fauna), Crowdy Bay National Park (for flora and fauna), Lake Innes Nature Reserve (for flora and fauna) and Limeburners Creek Nature Reserve (for flora and fauna).
286,000 ha were identified as above threshold for fauna at the limit of their range. 21% of this was on existing reserves and 48% in state forest. 295,000 ha were identified above threshold for flora at the end of their range. 33% of this was on existing reserves and 41% in State Forest (Table 10). Places already listed on the Register of the National Estate were strongly associated with the areas delineated as having values associated with species reaching the limit of their range. The south-west extension of Oxley Wild Rivers National Park is the only major listed site that did not having values contained within it.
TABLE 10: Land Tenure of indicative national estate species at the limit of their range


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

For Fauna

For Flora


60,021


97,627

21%


33%

State Forest

For Fauna

For Flora

137,713


120,044

48%


41%

Private Land


Not Available

Not Available

Leasehold Crown Land


Not Available

Not Available

Other Crown Land


Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


4.4 Flora and fauna refuges


The sharply incised landscape and variable environments of Upper North-Eastern NSW provide a diverse array of potential refugia. Heatwole (1987) noted the cyclic nature of climate in Australian geological history causing a series of long term wetter and drier periods that result in mesic and xeric species respectively radiating and contracting in the landscape. At the extremes of these cycles, species are restricted to small, favourable microhabitats in the landscape (refugia). Refugia are areas where physical and biological attributes combine to provide an environment that is more resilient to climatic variation, severe fire events and drought, than surrounding areas, and are important centres for the conservation of environmentally sensitive species. Consequently, refugia also constitute important sources of genetic variation and are regarded as important centres for species radiation when conditions become more favourable. For example, Horton (1984) regarded far northern NSW as refugia of long term significance to speciation in birds.
Refugia can be identified both as short term refuges from current perturbations such as fire, and long term evolutionary refuges. In the later case, the size of the refugia becomes significant. For example, it has been suggested that landscapes in which rainforests are extensive enough for a core areas to have remained comparatively stable during adverse climatic periods are highly likely to have primitive species or concentrations of narrow range endemic species that have disappeared from smaller rainforest areas in the landscape that shrink or disappear all together (Covacevich 1991).
Nix (1982) identified a number of areas down the east coast with high growth indices for species with thermal optimums in the range of 10-12oC and threshold temperatures around 0oC, including the edge of the Dorrigo plateau and the high parts of Barrington Tops. These disjunct areas support cool temperate rainforests, are similar to South-West Tasmania and high altitudes in New Guinea, and can be regarded as potential refugia (Nix1982, Commonwealth 1992). A range of other environments has already been discussed under endemic species and will be discussed under primitive and relictual species.
In summary, refugia are important for maintaining flexibility and adaptability in times of climatic change, as well as providing an insight into the vegetation of a past period, and the biogeographic and evolutionary processes, which have shaped the present biota. These areas are generally also important for many species now uncommon elsewhere (Sub-criterion B1, A1, A2 and D1).

4.4.1 Method

The national estate refugia coverage was derived using data from the lower north east RFA forest ecosystem coverage, a digital elevation model and the Broad Old Growth Mapping project (BOGM). Experts were asked to nominate environments important as refugia. These were then validated against the areas identified as important for primitive and relictual species and known locations that experts identified as being important for refugia.


Environments delineated included the following:


  • riparian, alpine, mallee, rock outcrops, native grasslands, subalpine, heath, banksia, wetlands, swamps, banksia, paperbark, casuarina, sedgelands, and coastal complex.

  • all rainforest polygons.

  • coastal occurrences of scribbly gum, swamp mahogany or cypress pine.

  • all ecosystems described as alpine or subalpine including ecosystems with black

sallee or snow gum present.

  • Roundleaf Gum with wet heath understorey.

  • a richness map of forest ecosystems showing the number of forest ecosystems within

two kilometres of each 100m grid cell was used to identify areas of steep

environmental gradient.


Geology was not available for LNE.

4.4.2 Establishing the threshold

Based on expert opinion, all refugia at any scale were important. No threshold was applied.



4.4.3 Results

Areas delineated as refugia are shown on map 11. Areas shown represent habitats nominated by experts as refugia, validated by comparison with the distribution of primitive and relictual species using best information available to the lower north east comprehensive regional assessment. All areas identified are significant concerning Australia’s evolutionary history, rare, endangered or uncommon flora and fauna and existing natural systems. The areas shown demonstrate principle characteristics of the range of Australia’s environments including wetlands, rainforests and coastal environments and are above the threshold warranted for national estate listing.


Refugia were found across the landscape of North-Eastern NSW. There were, however, concentrations of refugia along the rim of the Dorrigo Plateau and through the Macleay gorges to Werrikimbee National Park. Additional major concentrations occurred in Barrington Tops, Wollemi National Park and Brisbane Waters National Park. On the coastal plain foci for refugia occurred in Myall Lakes and Crowdy Bay National Parks, Lake Innes Nature Reserve, Limeburners Creek Nature Reserve and Hat Head National Park.
528,902 ha were identified as having potential indicative significance as refugia. Approximately 42% of the total area identified as refugia occurs in national park, flora reserve or nature reserve and 27% occurs on state forest (see table 11). Places already listed on the Register of the National Estate were strongly associated with the areas delineated as having values associated with species reaching the limit of their range.
TABLE 11: Land Tenure of indicative national estate refugia


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

221,736

42%

State Forest

142,615

27%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


4.5 Primitive, relictual, and phylogenetically distinct species


Relictual, phylogenetically distinct and/or Gondwanic flora and fauna species are generally regarded as those that meet one or more of the following criteria:


  • species that appear to possess primitive features;

  • species that exhibit features that appear to be different or remote from related species; and

  • species that appear to be populations left isolated in the landscape by later climatic or environmental changes.

The Rufous Scrub-bird (Atrichornis rufescens) is an example of a species generally agreed to have primitive taxonomic features and ancient origins within Australia. (Heatwole 1987). Phylogenetically distinct species were taken to be those species whose taxonomic affinities were unknown or unclear such as the Swamp Wallaby (Wallabia bicolor) which does not appear to be closely related to any of the other extant groups in the Macropodidae (Merchant 1995). The sphagnum frogs (Genus Kyarranus) are an example of a primitive group with ancient origins which, based on finds from Riversleigh fossil deposits, were once much more widespread but are now restricted to moist environments along the ranges (Barker et al 1995). Fletcher’s Frog (Lechriodus fletcheri) and the Southern Angle-headed Dragon (Hypsilurus spinipes) are examples of species with possible New Guinean or south-east Asian origins with relictual populations on the east coast, though recent genetic work suggests that Hypsilurus may actually have much older African origins (Hutchinson and Donnellan 1993, Tyler 1994).


North-Eastern NSW provides a variety of habitats suited to the persistence of primitive, relictual and phylogenetically distinct species. The diverse range of habitats, large altitudinal gradient and the presence of long-term stable landscapes such as mangroves, heath and rainforests all contribute to the likelihood of persistence of primitive, phylogenetically distinct and relictual species. The wide array of protected microhabitats such as sheltered gullies and rock outcrops provide contemporary refugia. Floyd (1985) noted that Australian rainforests possessed the greatest concentration of primitive families in the world. Of the 98 primitive angiosperm and gymnosperm genera in Australia, 42 genera are in North-Eastern NSW. Greenslade (1994) noted that Gondwanian relict species and taxa occupying geographically discrete sites such as mountain-tops were a high priority for national estate listing. Covacevich (1991) discussed the common Gondwanic origins of heaths and rainforest and related this to the modern similarities between the herpetofauna of heaths and rainforests in north-eastern NSW.
Primitive, relictual or phylogenetically distinct species are important as indicators of evolutionary history, past or current population movements, evidence of past or current speciation and for evidence of past or current decline (sub-criterion A1, A2).

4.5.1 Method

For fauna, workshops were used to identify fauna species with primitive, relictual or phylogenetically distinct characteristics to provide a species list. Literature reviews were also carried out to supplement the workshop responses. Data from the NSW NPWS wildlife atlas and data collected from CRA surveys were used. 19 primitive species and 25 relictual fauna species were identified. This was only done for fauna as experts did not nominate primitive or relictual flora species.


For flora and invertebrates, environments and known sites were identified through expert workshops and literature review. A coverage was derived using data from the UNE RFA forest ecosystem coverage, the geology sheet covering northern NSW (1:250,000 scale), and the results of the UNE CRAFTI API project. The environments identified were common to those nominated as refugia (see the sub-section on Refugia).
Point location information for all identified species was plotted for fauna on a one kilometre square grid. An analysis was done which then searched for all records within a two kilometre radius around each grid cell. The resultant analysis showed concentrations of primitive, relictual and phylogenetically distinct species across the landscape. This was combined with the landscape analysis conducted for flora and invertebrates to produce the final layer.

4.5.2 Establishing the threshold

The point location data was displayed as standard deviations above the mean number of species in the landscape. Two standard deviations above the mean number of species for fauna was taken to be above threshold.


Based on expert opinion, the primitive and relictual species habitat was thresholded to only show areas greater than 100 ha in area in the landscape. It was felt that the refugia layer was adequate to show the distribution of smaller units in the landscape.

4.5.3 Results

The areas identified as having indicative national estate significance for primitive, relictual and phylogenetically distinct species are delineated on Map 12. Areas shown represent an amalgamation of sites known to be rich in species with primitive, relictual or phylogenetically distinct fauna. These have been cross-referenced with habitats nominated by experts as important for fauna, flora or invertebrates, using the best information available to the lower north east comprehensive regional assessment. All areas identified are significant with regard to Australia’s evolutionary history and existing natural systems and are above the threshold warranted for national estate listing.


The areas delineated for this value were generally associated with protected wet environments such as the escarpment and Macleay gorges south of Dorrigo, Werrikimbee National Park, Wingham, Barrington Tops and Mount Royal and the deep gullies of the Watagans. Areas on the coastal plain tended to be associated with well-protected or particular environments. Examples include the tall wet flooded gum (Eucalyptus grandis) forests with Cabbage Tree Palm (Livistona australis) understoreys in Wallingat State Forest or the wet environs of Marsh State Forest.
348,500 ha were identified as above threshold for primitive, relictual and phylogenetically distinct species. 24% of this was on existing reserves and 41% in state forest. (Table 12). Areas already listed on the Register of the National Estate that were identified in this study as having values for primitive and relictual species tended to be those occurring along the great escarpment.
TABLE 12: Land Tenure of indicative national estate primitive, relictual and phylogenetically distinct species


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

83,400

24%

State Forest

143,900

41%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


Sub-Criterion A.2: Importance in maintaining existing processes or natural systems at the regional or national scale

The identification of areas of indicative national estate significance under this sub-criterion involves assessment of places important for the maintenance of natural ecosystem processes. These include abiotic processes (eg: those related to hydrological and nutrient cycles) and biotic processes (those related to the life cycles and interdependence of plant and animal species in the forests, woodlands, heathlands, sedgelands, swamps and wetlands of the region). Values that may be considered include:




  • habitat for migratory species

  • important wildlife habitat;

  • refuges for fauna (see refugia under Sub-criterion A1 above);

  • remnant vegetation; and

  • places important for vegetation succession.

Places important for undisturbed catchments and old-growth forest are addressed in extensive natural values.




4.6 Migratory species


Migratory species were regarded as those species which undertake a regular migration for breeding or feeding purposes at a regional, interregional, continental or intercontinental scale. In the context of northern NSW, this included bird species listed as JAMBA or CAMBA species as well as inter-regional migrants such as the dollarbird and forest migrants such as the grey-headed flying fox. Such species are important in maintaining existing processes and natural systems and help to delineate significant wetlands (Sub-criterion A2 and D1).

4.6.1 Method

Workshops were used to identify fauna species that were known to be migratory and which occurred within the region. Literature reviews were also carried out to supplement the workshop responses, including the inclusion of all species listed under JAMBA and CAMBA. The NSW NPWS wildlife atlas and data from the CRA surveys were used as the primary data source. 146 species were identified as migrants occurring within or visiting the RFA region.


Point location information for all identified species was plotted respectively for flora and fauna on a one kilometre square grid across the region. An analysis was done which then searched for all records within a two kilometre radius around each grid cell. The resultant analysis showed concentrations of migratory species across the landscape.
The site location for the only RAMSAR wetland in the region, Kooragang Island Nature Reserve was also included.

4.6.2 Establishing the threshold

The above information was displayed as standard deviations above the mean number of species in the landscape. Two standard deviations above the mean number of species was taken to be above threshold. The boundary of Kooragang Island Nature Reserve was added to the layer.



4.6.3 Results

The areas identified as having indicative national estate significance for migratory species is delineated on Map 13. Areas shown represent sites known to be rich in migratory species, using the best information available to the lower north-east comprehensive regional assessment. All areas identified are significant with regard to existing natural systems and are above the threshold warranted for national estate listing.


Areas delineated for migratory species were strongly associated with the coastal plain, noticeably, in coastal areas between Urunga and Port Macquarie, around Forster and between Newcastle and Gosford.
226,000 ha were identified as above threshold for migratory species. 21% of this was on existing reserves and 20% in state forest. (Table 13). The coastal parks and nature reserves including Crowdy Bay and Booti Booti National Parks, and Lake Innes and Kooragang Island Nature Reserves are indicative of the places identified in the current work that are places already listed in the Register of the National Estate.
TABLE 13: Land Tenure of indicative national estate migratory species


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

46,791

21%

State Forest

45,782

20%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


4.7 Important habitat


    Important fauna habitat is generally regarded as values such as important feeding, breeding or nursery sites or known breeding sites for rare or uncommon fauna. In Lower North-East, important habitat was used to define a number of environments that experts felt were of national estate significance or else that were identified for a wide range of species values. The Macleay River gorges, the forested parts of the Hunter valley, the bat foraging habitat around the major maternity roosts at Willi Willi and the Carrai plateau and the escarpment of the great dividing range were regarded as potentially significant. The Macleay river gorges, the Hunter valley and the great escarpment are major, long term corridors in the landscape, a view supported by Heatwole’s (1987) discussion on significant corridors and barriers in the landscape. Heatwole (1987) listed the evidence to suggested that the great dividing range has, over geological history, acted as a corridor for mesic-adapted species along the east coast, and as a significant barrier to the radiation of xeric-adapted species during drier periods from inland Australia. Worboys 91996) also identified the great escarpment as a major, continental-scale conservation feature. The Macleay and the Hunter valleys, however, represent some of the few corridors for xeric inland species to radiate onto the east coast during favourable climatic periods. Horton (1984) also identified south-eastern Queensland and northern NSW as a significant focus for bird speciation in Australia by acting as a major refuge.

The value is important for rare, vulnerable or endangered species, Australia’s evolutionary history, demonstrating the principle characteristics of forested landscapes and ecosystems and is related to maintaining existing processes (Sub-criterion A1, A2, B1 and D1).



4.7.1 Method

Expert opinion was used to identify environmental features that constituted important habitat, and to nominate areas known to be important. A map of the nominated environmental features meeting the expert opinion was generated and validated against areas identified as important habitat. The layer consists of the following:




  • all rainforest under 300 m above sea level.

  • forested areas of the great escarpment and around Carrai and Willi Willi (between 300 and 900 m ASL, using biophysical naturalness 2, 3, 4 and 5 to delineate approximate areas of woody vegetation).

  • areas with concentrations of winter flowering eucalypts (taken to be eucalypts with more than 50% of their flowering between June and September on average) based on a forest ecosystem analysis and area/richness across a 100m grid.



4.7.2 Establishing the threshold

The layer was cut to remove areas that have been cleared or substantially modified using biophysical naturalness values 0 and 1. A 100 ha minimum size was applied to all identified areas with the exception of rainforest, for which there was no minimum size threshold applied because of the importance of lowland remnants.



4.7.3 Results

The areas identified as having indicative national estate significance for important habitat is delineated on Map 14. The areas delineated in this layer are those environments nominated by experts for an array of values relating to important habitat including migratory species, evolutionary processes in the landscape and the diversity of small mammals. Areas shown were delineated using the best information available to the lower north east comprehensive regional assessment. All areas identified are significant with regard to Australia’s evolutionary history, existing natural systems, principle characteristics of forested landscapes and rare or uncommon species and are above the threshold warranted for national estate listing.


The areas delineated for important habitat describe a broad band of forested landscapes from the Dorrigo Plateau southwards around the catchment of the Macleay, Hastings and Manning Rivers to Barrington Tops. The layer is broken by the intrusion of the cleared landscape of the Hunter Valley and commences again in Wollemi and Yengo National Parks. Coastal areas delineated include the Watagans, the Wallaroo group of State Forests, Myall River State Forest, Myall Lakes National Park, the Kendall group of State Forests, Yesabah State Forest and Ingalba State Forest. These coastal areas were generally above threshold for concentrations of winter flowering species, maternity roost foraging habitat for bats or significance as habitat for small mammals. The areas identified as above threshold generally reflect the significance of the coastal plain as a whole for migratory or nomadic nectivorous species.
1,626,000 ha were identified as above threshold for important habitat. 34% of this was on existing reserves and 30% in state forest. (Table 14). Areas already listed on the Register of the National Estate that were identified in this study as having values for important habitat species tended to be those occurring along the great escarpment.
TABLE 14: Land Tenure of indicative national estate important habitat


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

556874

34%

State Forest

481,753

30%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


4.8 Remnant vegetation and rare old-growth forest


Remnant vegetation provides important refuge and recruitment areas for both flora and fauna, and is important in maintaining existing natural systems within disturbed landscapes. Large-scale clearing for agriculture on the coastal plain and west of the Great Dividing Range has removed native vegetation from extensive areas of the region. Much of the remaining forest is fragmented and significant proportions have a long history of commercial forestry operations.
Rare old-growth forest was assessed together with remnant vegetation as many of the conservation issues are closely related. Rare old-growth forest are those old-growth forest communities that are rare or uncommon nationally or within the lower north east region. They also include common forest communities where the levels of disturbance are such that all remaining old-growth forest areas are potentially of national estate significance. Rare, endangered or uncommon old-growth forest communities were identified in lower north east as being vegetation communities where old-growth forest as a proportion of the forest community is generally less than 20 per cent (derived from the JANIS criteria and expert advice).
Remnant vegetation is important for demonstrating the principle characteristics of forested landscapes and ecosystems, rare or uncommon species and is related to maintaining existing processes (Sub-criterion A2, B1 and D1).

4.8.1 Method

Remnant vegetation and rare old-growth forest was derived using the following:




  • Forest ecosystems whose extant coverage was 10% or less of the estimated pre-1750 area based on data presented by NSW NPWS to the environment heritage and technical committee (EHTC); and




  • Forest ecosystems intersected with biophysical naturalness 4 and 5. Forest ecosystems that had less than 20% of their area covered by undisturbed forest compared with their pre-1750 area were regarded as rare old-growth forest. The forest ecosystems used were those listed in the forest ecosystem table presented as the final data-set at EHTC.



4.8.2 Establishing the threshold

Areas that met the above criteria were identified as above threshold.



4.8.3 Results

The areas identified as having indicative national estate significance for remnant vegetation and rare old-growth forest are delineated on Map 15. The areas delineated in this layer are those identified as significant with regard to existing natural systems, principle characteristics of forested landscapes and rare or uncommon species and are above the threshold warranted for national estate listing.


Remnant vegetation occurs as scattered small units across most of the region, with the greatest concentrations in undisturbed areas along the escarpment and in the coastal national parks and nature reserves. Particularly significant areas included Barrington Tops, Bulga and Doyles River State Forests, Werrikimbee National Park and the edge of the Dorrigo plateau.
296,426 ha were identified as above threshold for remnant vegetation and rare old-growth forest. 45% of this was on existing reserves and 40% in state forest. (Table 15). The major landscapes in the layer included all of the significant sites already nominated on the Register of the National Estate north of the Hunter River.
TABLE 15: Land Tenure of indicative national estate remnant vegetation and rare old-growth forest


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

133,665

45%

State Forest

117,704

40%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


4.9 Vegetation succession


Places that are important for vegetation succession are forest communities that have dynamic examples of succession occurring within them, areas affected by fire (halting primary succession processes), and forest communities recovering from major wildfires. Although it was recognised that specific examples may exist in the region, time and data constraints precluded any specific analysis of vegetation succession for lower north east.


Sub-Criterion A.3: Importance in exhibiting unusual richness or diversity of flora

The identification of areas of indicative national estate significance under this sub-criterion involves assessment of places important for diversity and or richness of natural values. The national estate assessment of this value sought to identify areas of particular richness and diversity in the region for:




  • species richness (alpha diversity);

  • flora community (beta) diversity;

  • habitat richness.


4.10 Flora and fauna species richness


Flora and fauna species richness, also known as alpha diversity, is measured as the number of species occurring within an area of a given size. Upper North-Eastern NSW comprises an area of diverse habitats from sub-alpine environments to coastal complexes and sub-tropical rainforest and the region has been widely recognised as an area important for biodiversity. Areas of high species richness can be indicative of sites where repeated species radiation and contraction has occurred, identifying centres for refugia and major long-term evolutionary centres for speciation (Heatwole 1987, Pianka (1981), Kitching 1981, Cogger and Heatwole, 1981, 1984). Species richness is considered under sub-criterion A3 for exhibiting unusual richness or diversity of fauna or flora.

4.10.1 Method

The fauna layer was derived using fauna point data provided by the NPWS wildlife atlas and CRA survey work. 655 species were included in the analysis, excluding introduced species only. The flora layer was derived using flora point data provided by the NPWS derived from atlas, literature review and CRA survey. 1713 species were used in analysis.


Point location information for all identified species was plotted respectively for flora and fauna on a one kilometre square grid. An analysis was done which then searched for all records within a two kilometre radius around each grid cell. The resultant analysis showed concentrations of species richness for fauna and flora respectively, across the landscape.
This layer was validated by comparing the areas depicted in the layer with areas that experts identified as being important for species richness.

4.10.2 Establishing the threshold

The above information was displayed as standard deviations above the mean number of species in the landscape. Two standard deviations above the mean number of species for both flora and fauna was taken to be above threshold.



4.10.3 Results

The areas identified as having indicative national estate significance for species richness are delineated on Map 16 for fauna and Map 17 for flora. The areas delineated in this layer are areas with high concentrations of species in the landscape, delineated using the best information available to the lower north east comprehensive regional assessment. All areas identified are significant with regard to exhibiting unusual richness or diversity of fauna or flora and are above the threshold warranted for national estate listing.


Areas that were delineated for species richness were broadly similar for fauna and flora. The delineated areas identified a number of core hot-spots in the landscape. These were: the rim of the Dorrigo plateau, the Carrai plateau, Werrikimbee National Park and Mount Boss State Forest, Doyles River, Bulga and Dingo Tops State Forests, Barrington Tops, Lake Innes Nature Reserve, Crowdy Bay and Booti Booti National Parks, Tomaree National Park and the Watagans - Ourimbah forest area including Brisbane Waters National Park.
381,100 ha were identified as above threshold for fauna species richness. 23% of this was on existing reserves and 38% in state forest. 360,000 ha were identified above threshold for flora species richness. 30% of this was on existing reserves and 43% in State Forest (Table 16). Places already listed on the Register of the National Estate were strongly associated with the areas delineated as having values associated with species richness.
TABLE 16: Land Tenure of indicative national estate species richness


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

For Fauna

For Flora


85,900


107,00

23%


30%

State Forest

For Fauna

For Flora

144,200


154,100

38%


43%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)

4.11 Vegetation community richness


Significant plant community richness, or high beta diversity, is often seen in places where, because of sharp environmental gradients or marked changes in soils, drainage or other variables, there are unusually diverse conjunctions or rapid transitions of forest community types. In North-Eastern NSW these environments are typified by the elevation gradient of the great escarpment and associated river gorges, where vegetation communities vary over a comparatively small distance. This value is important for sub-criterion A3, exhibiting unusual richness or diversity of flora.

4.11.1 Method

The CRA forest ecosystem map was used to assess and identify areas above threshold. A 100m grid was laid across the whole of lower north-eastern NSW and then the number of forest ecosystems within a radius of two kilometres of each grid cell was calculated. This produced a map of the richness of forest ecosystems across the landscape.



4.11.2 Establishing the threshold

Areas were regarded as being above threshold for vegetation community richness where the number of forest ecosystems in a 100m cell were more than 2 standard deviations above the mean number of forest ecosystems in any cell.



4.11.3 Results

The areas identified as having indicative national estate significance for vegetation community richness are delineated on Map 18. The areas delineated in this layer are areas with high concentrations of vegetation communities in the landscape, delineated using the best information available to the lower north east comprehensive regional assessment. All areas identified are significant with regard to exhibiting unusual richness or diversity of flora and are above the threshold warranted for national estate listing.


The areas delineated as above threshold for vegetation community richness are strongly associated with the escarpment of the northern part of the Great Dividing Range from the Manning valley north and associated river gorges where the greatest altitudinal range exists.
277,868 ha were identified as above threshold for vegetation community richness. 32% of this was on existing reserves and 12% in state forest. (Table 17). Dorrigo National Park, Oxley Wild Rivers National Park, and Woko National Park are indicative of the places identified in the current work that are places already listed in the Register of the National Estate.
TABLE 17: Land Tenure of indicative national estate vegetation community richness


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

89,751

12%

State Forest

32,219

32%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


4.12 Habitat richness


Habitat richness has been defined as areas where, because of environmental gradients, there is an unusual increase in the variety of habitats available. This was taken to involve an interaction between vegetation community richness, fauna species richness and flora species richness and is important as an indicator for areas of potential high biodiversity (Sub-criterion A3).

4.12.1 Method


Habitat richness is a grid coverage derived by adding the areas identified as above threshold for flora and fauna species richness together into a single layer. This combined layer was then combined with the vegetation community richness layer. The areas identified as possessing either a combination of flora and fauna richness or vegetation community richness were regarded as having habitat richness.

4.12.2 Establishing the threshold

Areas that met the above criteria were regarded as being above threshold.



4.12.3 Results

The areas identified as having indicative national estate significance for habitat richness are delineated on Map 19. The areas delineated in this layer are areas with high concentrations of potential habitat richness in the landscape, delineated using the best information available to the lower north east comprehensive regional assessment. All areas identified are significant with regard to exhibiting unusual richness or diversity of fauna, flora or vegetation community richness and are above the threshold warranted for national estate listing.


Areas delineated as above threshold were concentrated on along the escarpment and adjacent ranges in a series of units from the Macleay gorges to Barrington Tops. Coastal pockets included Crowdy Bay National Park, Booti Booti National Park and Tomaree National Park
426,300 ha were identified as above threshold for habitat richness. 32% of this was on existing reserves and 20% in state forest. (Table 17). The area delineated included areas of existing National Estate, the major areas being Oxley Wild Rivers National Park, Werrikimbee National Park, Crowdy Bay National Park and Woko National Park.
TABLE 17: Land Tenure of indicative national estate habitat richness


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

135,138

32%

State Forest

85,451

20%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


Sub-Criterion B1: Importance for rare, endangered or uncommon flora, fauna, communities, ecosystems, natural landscapes or phenomena, or as a wilderness

This sub-criterion recognises the importance of biotic elements which are rare or uncommon, or have become so through the effects of disturbances or threatening processes. The following values relate to this sub-criterion:




  • rare old-growth forest;

  • rare and threatened flora and fauna species, and

  • rare, threatened or uncommon plant communities.


4.13 Rare old-growth forest


Rare old-growth forest has been dealt with as part of the remnant vegetation layer (see section on sub-criterion A2.


4.14 Rare, threatened or uncommon flora and fauna species and their habitats


For the purposes of this layer, rare species were regarded as species listed on state or commonwealth legislation as rare, vulnerable or endangered. This layer identifies areas of importance to rare, endangered or uncommon species and which are of significance in maintaining existing processes. (Sub-criterion B1, A2)

4.14.1 Method

The rare species layers for fauna and flora respectively was produced from two separate analysis:




  • All Commonwealth and state listed species were used in a neighbourhood analysis. This produces a grid coverage where each 1 kilometre grid cell is given a value equating to the total number of species recorded within a 2 kilometre radius of the cell. The resulting 1 kilometre grid provides a map of the concentration of rare species across the landscape.




  • The point localities of Commonwealth and state listed endangered species were intersected with forest ecosystem polygons within 500m of their point location.

The two layers were merged and the final data set was intersected with biophysical naturalness value 0 and 1 to remove values in cleared and extensively modified landscapes. The final layer was validated against areas suggested by experts, a selection of species locality points and the results of modelling conducted by NSW NPWS.



4.14.2 Establishing the threshold

One kilometre grid cells with a total number of species greater than or equal to 2 standard deviation above the mean number of species were regarded as above threshold. All point localities of endangered species in a forested or uncleared natural locality were regarded as above threshold.



4.14.3 Results

The areas identified as having indicative national estate significance for rare species are delineated on Map 20 for fauna and Map 21 for flora. This layer delineates areas that are important for endangered species and areas with concentrations of rare and uncommon species. The layer uses the best information available to the lower north east comprehensive regional assessment. All areas identified are significant with regard to importance for rare, endangered or uncommon species and maintaining existing natural processes.


The layers for fauna and flora delineated similar (but not identical) areas in the landscape as being above threshold. Flora and fauna values were identified along the edge of the Dorrigo plateau and fauna values were identified in the Macleay catchment , Carrai Plateau and Werrikimbee National Park. Rare fauna values were concentrated in Doyles River, Dingo Tops, and Bulga State Forests and flora and fauna values were concentrated in the Barrington Tops. Rare fauna were found to be concentrated in a number of locations on the coastal plains including Ingalba State Forest, Limeburners Creek Nature Reserve, Coopernook State Forest, Craven, Myall River and Wang Wauk State Forests and Putty State Forests.
421,000 ha were identified as above threshold for rare fauna. 29% of this was on existing reserves and 49% in state forest. 37,400 ha were identified above threshold for rare flora. 59% of this was on existing reserves and 19% in State Forest. (Table 18). The analysis identified most significant existing places on the Register of the National Estate as having values associated with this criterion.
TABLE 18: Land Tenure of indicative national estate rare species


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

For Fauna

For Flora


123,798


22,002

29%


59%

State Forest

For Fauna

For Flora

204,760


7,037

49%


19%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


4.15 Rare, threatened or uncommon vegetation communities


In the lower north east comprehensive regional assessment ‘forest ecosystems’, ‘plant communities’ and ‘forest vegetation types’ are all considered to refer to the same vegetation units and are used interchangeably. Rare vegetation communities are important for demonstrating the principle characteristics of forested landscapes and ecosystems, and endangered, rare or uncommon species and is related to maintaining existing processes (Sub-criterion A2, B1 and D1).

4.15.1 Method

The expert workshop that considered the results of the forest ecosystem project identified that all vegetation communities that required a 100% target under JANIS were above threshold for national estate. The distribution of these communities was mapped from the forest ecosystem layer. All occurrences of these ecosystems were regarded as above threshold.



4.16.2 Establishing the threshold

Thresholds were established as discussed above.



4.16.3 Results

The areas identified as having indicative national estate significance for rare vegetation communities are delineated on Map 22. The areas delineated in this layer are rare vegetation communities, identified using the best information available to the lower north east comprehensive regional assessment. All areas identified are significant with regard to endangered, rare or uncommon species, demonstrating the principle characteristics of some extremely uncommon vegetation communities and maintaining existing processes. These areas are above the threshold warranted for national estate listing.


The areas above threshold for rare vegetation communities are broadly distributed across the landscape of lower north-eastern NSW, with the strongest concentration along the escarpment and adjacent coastal ranges. Major focal points include the edge of the Dorrigo plateau and Macleay gorges, Carrai Plateau, Werrikimbee National Park, Doyles River and Bulga State Forests, Woko National Park and Barrington Tops.
281,916 ha were identified as above threshold for rare vegetation communities. 43% of this was on existing reserves and 42% in state forest. (Table 19). The areas identified as above threshold correlated strongly with places registered on the Register of the National Estate along the escarpment to Barrington Tops.
TABLE 19: Land Tenure of indicative national estate rare vegetation communities


Tenure

Approximate Area (ha)

Proportion of Total (%)

National Park, PMP 1.3 or Nature Reserve

120,063

43%

State Forest

119,237

42%

Private Land

Not Available

Not Available

Leasehold Crown Land

Not Available

Not Available

Other Crown Land

Not Available

Not Available

*PMP 1.3 is the State Forests of NSW Preferred Management Priority Classification for areas reserved as Flora Reserves and Forest Preserves (Forestry Commission of NSW 1993)


Sub-Criterion D.1: Importance in demonstrating the principal characteristics of the range of landscapes, environments or ecosystems, the attributes of which identify them as being characteristic of their class.

This sub-criterion recognises the significance of identifying and conserving ‘representative examples’ of the range of features of the Australian environment. The following value was assessed under this sub-criterion.




  • flora communities characteristic of their class.



4.16 Principal characteristics of class


Principle characteristics of class recognises the significance of identifying and conserving “representative examples” of the range of landscapes, environments or ecosystems. Although some vegetation communities were considered and it was recognised that representative examples may exist in the region, time and data constraints precluded any comprehensive analysis of principle characteristic of class for environments or ecosystems. It should be noted that the work conducted for refugia, migratory species, remnant vegetation, rare vegetation communities, and important habitat identified particular landscape features such as wetlands or rainforest and broader features such as forested landscapes along the great escarpment that should be regarded as some of the best examples in temperate Australia and that the sub-sections dealing with these values have been noted as dealing with D1.



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