Lichen covered Rock - SAVE MT Canobolas SCA

A Natural Laboratory

Mt Canobolas SCA is a natural laboratory providing many fertile avenues for research and education. It functions as both a refugium for declining species and an evolutionary nursery for new species. At least ten scientific institutions or organisations use the SCA and much remains to be understood – limited formal studies of biota have been undertaken.

Ecological processes or ecological integrity

The vegetation communities on Mt Canobolas are the result of ecological and evolutionary processes operating over millions of years. They have evolved in relative isolation to become recognisably distinct from similar communities elsewhere. Accordingly, the vegetation communities of Mt Canobolas provide examples of the ecological responses of vegetation assemblages to isolation, longitudinal displacement and climatic gradients.

One indicator of continuing ecological integrity is the number of terrestrial orchids found in the SCA. Upwards of 35 species have been recorded. Orchids are particularly sensitive to disturbance from overgrazing and nutrient influxes, hence the diversity is indicative of high resilience within the SCA ecosystems.

Outstanding ecological value for education or scientific research

The importance of Mt Canobolas as a centre of endemism is becoming increasingly evident to the scientific community. Research on various cryptogams, vascular plant taxa and invertebrates in the SCA is being, or has been, undertaken by the Department of Biological Sciences, Macquarie University (bryophytes, Velvet worms), Royal Botanic Gardens and Domain Trust, Sydney (Prostanthera gilesii), Botany School at the University of New England, Armidale (various flowering plants), Research School of Chemistry, Australian National University (lichens), David Jones (Associate of the Centre for Australian National Biodiversity Research, Canberra) (orchids), National Museum of Victoria (insects), Australian National Insect Collection, Canberra (beetles), The Australian Museum Sydney (insects) and the Biosecurity Collections Unit of NSW DPI in Orange (leafhoppers, moths). The SCA provides abundant opportunities for further taxonomic research.

The less vagile plant and animal communities on Mt Canobolas have evolved over millions of years in relative isolation. This has resulted in recognisably distinct assemblages that differ from communities in similar environments elsewhere. Accordingly, the biodiversity of Mt Canobolas provides examples of the ecological and evolutionary responses of an entire landlocked island biota to isolation, longitudinal displacement and climatic gradients, providing many fertile avenues for research and education.

Evolutionary processes – vicariance versus refugium

The presence of multiple endemic species in diverse groups of flora and fauna in the SCA reflects the geographic isolation of Mt Canobolas as a landlocked island of high altitude habitats that provides an ideal environment for species evolution. After the Late Miocene when the Mt Canobolas volcanic complex had ceased activity the land surface of the eastern highlands would have been much higher with alpine and sub-alpine vegetation considerably more widespread and interconnected than it is today. A long period of erosional activity has lowered the land surfaces resulting in the contraction and fragmentation of sub-alpine habitats which ultimately led to the stranding of remnant communities and populations on Mt Canobolas. The isolation of Mt Canobolas has been in place for long enough to the allow the evolution of multiple new life forms, a process known as evolution by vicariance, essentially by the splitting of populations into isolated fragments that subsequently evolve independently. Consequently, it is likely that many of the endemic species with close relatives elsewhere have evolved into new species on Mt Canobolas by vicariance.

As well as functioning as an evolutionary nursery for new species, Mt Canobolas also appears to function as a refugium for declining species, that have become extinct elsewhere. Consequently, low connectivity has likely been a principal driver influencing the diversity of the less vagile elements of the biota. It is the reason why the unique creatures like the yellow planarian worm, the Mt Canobolas Velvet Worm and other endemics, such as some of the lichens, are restricted to the mountain. For these species Mt Canobolas is likely to be their last refuge on the planet.

In either event, the presence of these endemic species in the SCA is scientifically important and provides fascinating opportunities for research.

Climate change refugium

Connectivity at a landscape level assumes importance for the recorded migratory birds and mammals such as bats and gliders utilising the food and nesting resources provided by the SCA.  Natural remnants form a south-west corridor through Edenboro Reserve [Crown Land] and parts of Canobolas State Forest around Lees Mountain and Lapstone Hill. These link with a long tongue of remnant woodlands through Black Rock Ridge [Cadia Valley Operations Bio-offset] and nearby Colombine Mountain [Private Land]. To the west there are native remnants on Black Mountain, Paling Yards Reserve [Crown Land] and these link with Barton Nature Reserve. Further along the western slopes are Conimbla National Park (NP), Nangar NP and the extensive Goobang NP extending from Bumberry to the northern Harvey Range. These lower altitude remnants are tentacles leading to Mt Canobolas which clearly hosts migratory species of mammals such as micro bats and birds such as the threatened robin species. Within a 50 km radius to the north and east are the Mullion Range SCA, Girralang Nature Reserve (NR), Freemantle NR, Hill End Historic Site (HS) and Winburndale NR whilst Copperhannia NR lies to the south. A small remnant known as The Pinnacle lies nearby to the east of the SCA.

Because of the large altitudinal range (900 to 1400 m) within the SCA and the connecting vegetated ridges to the surrounding lower lands, Mt Canobolas has high importance as a potential climate refuge. As temperatures warm, native vegetation communities characteristic of the lower altitudes surrounding the mountain, and their biota, may follow their favoured climatic conditions upwards within the volcanic complex. Given there is no other similar high altitude land system within the western Central Tablelands, Mt Canobolas assumes critical importance for the survival of the distinctive biodiversity of the volcanic complex in a warming world, offering further opportunities for study.

Photo credit: Endemic rock lichens Photo by Helmut Berndt

Unique and Irreplaceable Biodiversity    |    Threatened Species