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Monitoring biodiversity in jarrah forests

  • Forests and woodlands are important habitats that support much of the biodiversity of south-west Western Australia.
  • They are also widely used for recreation, and create social well-being.
  • Some areas are an important source of forest products such as timber and minerals.

Managing our forests and woodlands—whether for nature conservation, recreation, timber production or mineral extraction—has an impact on the ecology, influencing the plants and animals living there.

Monitoring these impacts provides us with valuable information about their effects on forest biodiversity. This information allows us to make decisions that ensure our forests survive and thrive into the future.

jarrah forest
Jarrah forest - Photo © Parks and Wildlife

What we do

  • FORESTCHECK is an integrated monitoring project, designed to provide information to forest managers about changes and trends in biodiversity associated with forest activities.
  • FORESTCHECK samples a wide range of organisms at multiple sites across the jarrah forest.
  • FORESTCHECK was developed with input from scientists and managers within the Department of Parks and Wildlife, and from universities and other government agencies. Monitoring began in 2002.
  • The project stems from state, national and international obligations to ensure that our forests and woodlands are managed in an ecologically sustainable manner.
    FORESTCHECK data has been used:

FORESTCHECK:

  • makes a significant contribution to forest science
  • informs forest managers on changes and trends in key elements of forest biodiversity
  • provides a framework for meaningful public participation in forest management
  • provides relevant information to allow the department to comply with reporting requirements associated with sustainable forest management
  • contributes to global-scale studies on impacts on biodiversity.
  • FORESTCHECK currently focuses on timber harvesting and silvicultural treatments in jarrah forests in south-west Western Australia.
    In the future, FORESTCHECK may be extended to monitor the impact of other forest activities including:
    • fire (prescribed and bushfire)
    • climate change
    • mining
    • utility corridors (roads, power transmission lines)
    • recreational use.
    Coral vine - Photo © Parks and Wildlife

    Why is FORESTCHECK special?

    • FORESTCHECK collects data from all groups of organisms from the same point in time and space using standardised collection methods.
    • This integrated approach allows for more accurate studies on the interactions between organisms and the effects of management activities on biodiversity as a whole.
    • FORESTCHECK monitors total species richness, abundance and composition of all monitored organisms. This differs from other monitoring projects that tend to focus on individual species and community groups.

    In addition, FORESTCHECK:

    • is a synchronised monitoring project that enables valid comparisons from year to year between organisms and the attributes measured.
    • can operate without having to make assumptions about the varying environmental and climatic conditions recorded in separate studies with smaller criteria.
    • allows for a large proportion of biodiversity to be monitored (including the 'forgotten elements' such as fungi and lichens).
    • uses a single database to record forest attributes, climatic factors, management history (timber harvesting, prescribed fire) and fire history. This allows for a more integrated approach to monitoring.

    Life in the jarrah forest - Photo © Parks and Wildlife

    What does FORESTCHECK monitor?

    Since 2002, FORESTCHECK researchers have gathered data on approximately 3900 species that live in the jarrah forests of south-west Western Australia.
    Information has been collected on both native and non-native species (such as weeds and feral animals), and includes:

    • fungi
    • lichens, mosses and liverworts
    • flowering plants
    • invertebrates, including insects, over one centimetre in length
    • birds (nocturnal and diurnal)
    • terrestrial mammals (nocturnal and diurnal)
    • reptiles and frogs
    • physical attributes of the forest including stand structure and regeneration stocking
    • leaf and soil nutrients
    • litter loads and the amount and condition of coarse woody debris
    • degree of soil disturbance/soil compaction due to timber harvesting.

    What areas are being monitored?

    FORESTCHECK researchers have set up 67 permanent monitoring grids in 7 locations throughout the jarrah forest.

    • Southern jarrah (Donnelly, 10 grids)
    • Central jarrah (Wellington, 9 grids)
    • Northern jarrah (Perth Hills, 8 grids)
    • Eastern jarrah (Wellington East, 10 grids)
    • Sunklands (Blackwood Plateau, 11 grids)
    • Southern jarrah (Donnelly, 9 grids)
    • Sandy basins (Blackwood, 7 grids)
    • 'time since fire' grids (Perth Hills, 3 grids)
  • FORESTCHECK grid locations small
    FORESTCHECK grid locations
    Larger Graph

     These sites include grids in:

    Unlogged forest
    Reference sites that have never been logged, or were logged more than 40 years ago, and will not be harvested in the future. These include grids in national parks, conservation reserves, fauna habitat zones and coupe buffer zones.


     

     

    Unlogged jarrah forest
    Unlogged jarrah forest

    Shelterwood harvested forest
    Shelterwood harvesting is the partial removal of trees to encourage seedlings to establish and develop within the forest stand. Sufficient overstorey is retained to provide a seed source and maintain forest values while seedlings develop. This practice is used when trees are ready to be felled but there are an inadequate number of saplings to take their place.

     


     

    Shelterwood treatment in a jarrah forest
    Shelterwood treatment in a jarrah forest
    Gap release harvested forest
    Gap release harvesting is the near-complete removal of the overstorey to allow saplings to develop without obstruction, and to eventually become a new forest. It is used when there is an adequate supply of saplings.


    Gap release treatment in a jarrah forest
    Gap release treatment in a jarrah forest

     

     

     

     

     

     

     
















    One location is monitored each year.

    • There are eight to 11 monitoring grids at each location.
    • Each grid covers two hectares.

    At each location, sets of grids are closely matched in terms of:

    • forest vegetation complex
    • site characteristics such as
      • climate
      • geomorphology
      • soils
      • topography
      • altitude
      • aspect
    • treatment history including:
      • time since logging
      • time since fire.

    This ensures that differences between grids reflect the effects of harvesting rather than inherent site differences.

    All data is entered into a database and managed centrally.


    How we monitor biodiversity in jarrah forest managed for sustainable forestry

    For each grid site:

    • record species richness and abundance
    • determine the species composition within each treatment
    • analyse trends in species richness, abundance and composition between treatments, as well as other characteristics specific to each group.

    FORESTCHECK researchers use a variety of methods to monitor biodiversity.

    Fungi
    Lichens, mosses and liverworts

     Method: Transects

    • Researchers walk along a fixed path, one metre wide and 200 metres long. The number and type of all species (known and unknown), and the habitat and host material preferred by each species, are recorded along three transects on each grid.
    • Fungi are plentiful, but only those that produce visible fruiting bodies late in autumn, following the winter rains, are recorded.

    Many lichens, mosses and liverworts blend well into their surroundings, and seeing them requires a keen eye.

    Image
    Transect line

    Flowering plants

     Method: Plots

    • Researchers document plant species and their abundance within six 1,000- square- metre plots on each monitoring grid.
    • The amount of cover the plants provide and the physical structure of the understorey vegetation is also measured.

     

    plots
    Plots

    Invertebrates (including insects)

    Methods: Light traps, pitfall traps, foliage beating
    Insects, alone, are so numerous that it would take a disproportionate amount of time to identify them. FORESTCHECK researchers record only those larger than a centimetre unless they are a distinctive or targeted species.

    • Many insects are well hidden or only emerge at night, so recording species like the Dryandra moth (Carthaea saturnioides) requires capturing them using light traps. A large number of insect species are attracted to light. Most light traps use fluorescent bulbs to keep insects 'glued' to a surface until they can be collected.
    • Ground-dwelling insects such as crickets, and other invertebrates such as scorpions, are caught in small pitfall traps (containers buried in the ground).
      Insects fall into the traps and are unable to escape.
    • Branches are beaten and shaken to dislodge insects onto a large sheet or tarpaulin to collect species, such as weevils, that live in the foliage of understorey trees and shrubs.

    We also record the presence of Gondwanan relics—species that have survived in the south-west from the time of the ancient Gondwanan forests over 100 million years ago.

    Pest species, such as the pdfgum leaf skeletoniser which defoliates eucalypts, are also monitored.

    Pitfall trap
    Pitfall trap


    lighttrap

    A light trap captures Helena gum moths (Opodiphthera helena)

    Birds (nocturnal and diurnal)

    Methods: sight and sound, spotlight transects

    Birds are identified during the day and at night.

    Researchers look and listen for birds along a transect.

    Boobook (Ninox boobook) and masked owls (Tyto novaehollandiae) have been recorded during night spotlight studies.

    • Birds are identified during the day and at night.
    • Researchers look and listen for birds along a transect.
    • Boobook (Ninox boobook) and masked owls (Tyto novaehollandiae) have been recorded during night spotlight studies.

    Southern boobook (Ninox boobook)

    Mammals (terrestrial mammals, nocturnal and diurnal)
    Reptiles and frogs 

     Methods: wire traps and pit traps

    • Pitfall trapping is used for small mammals and reptiles.

      A smooth-sided bucket is dug into the ground and a low fence installed that leads to the pit trap. Reptiles and small animals run along this fence and fall into the pit trap. Others simply jump into it.

    • Specially designed wire cages are baited with a peanut butter and oat mixture to lure larger mammals into them. The cages have a treadle mechanism that releases the door and trap the unsuspecting mammals,such as echidnas, pygmy possums and dunnarts.  The numbers of mammals are very low in areas that have not been baited for foxes.

    All captured mammals, reptiles and frogs are weighed, tagged (or temporarily marked) and then released.

    All animal trapping is conducted under strict Australian Government animal ethics guidelines and regulated by Parks and Wildlife's animal ethics committee.

     

    Pit Traps
    Pit Traps

    Wire traps
    Wire traps

    Forest attributes

    Methods: Various

    Physical attributes of the forest, such as leaf and soil nutrients, are assesed by chemical analysis.

    The amount of coarse woody debris and litter in the forest is measured by plots and transects.

    • Litter is material less than six millimetres in diameter. This is measured with a defined circle using a metal cylinder
    • Small twigs are between seven and 25 millimetres in diameter, and is sampled within a small, defined plot
    • Coarse woody debris debris (snags, fallen logs, wind-blown trees and large branches greater than 2.5 centimetres in diameter) is measured along a defined transect. Decomposition of this material returns nutrients and carbon to the soil. Coarse woody debris provides nesting sites for forest animals and habitat for other organisms that are decomposers or form components of forest food webs.

    Log extraction tracks and landings around the grids are mapped using GPS. The degree of soil disturbance and compaction due to forestry practices is then measured by soil core sampling.

    Equipment for sampling litter and small twigs
    Equipment for sampling litter and small twigs

    Soil disturbance from harvesting machinery
    Soil disturbance from harvesting machinery


  • four images of the same forest area showing recovery after fire
    Fire is not excluded from FORESTCHECK sites, but recovery is monitored over time. Unlogged forest unburnt for 27 years (top left), burnt by wildfire Jan 2005 (top right), regrowth Sep 2005 (bottom left) and regrowth 2010 (bottom right)
    - Photo © Parks and Wildlife

    FORESTCHECK and fire

    FORESTCHECK is a monitoring program, not a scientific experiment, so FORESTCHECK sites are not excluded from prescribed burning programs.

    • Prescribed burning usually occurs within two years of timber harvesting, and then recurs five to 10 years later, depending on fuel accumulation rates, available burning days and human resources.
    • In the case of bushfire or unplanned fire, FORESTCHECK grids are not specifically protected.
    • Machine and equipment associated with fire suppression is, however, excluded from grids to ensure that monitoring of soil compaction and disturbance from timber harvesting activity is not compromised.
    • Records of all prescribed and unplanned fires are kept. This enables forest recovery after a fire to be tracked and, over time, the impact of fire can be separated from the impact of logging.
    • FORESTCHECK fire strategies are being used in other Parks and Wildlife projects that involve a more systematic examination of the effects of various fire regimes on biodiversity.

    Results and research

    The information gained from FORESTCHECK highlights the extraordinary diversity of life that thrives in the jarrah forest.

    • Compared with flowering plants and vertebrates, studies on the classification of invertebrates, fungi and lichens are limited, yet these three groups accounted for 84 per cent of the total biodiversity recorded by FORESTCHECK in the first 10 years.
    • An abundance of relatively unknown species of invertebrates, fungi and lichens have been documented, many of which were collected and recorded for the first time, and are yet to be named.
    • Timber harvesting in the jarrah forest does not appear to have had a major impact on the number of species present.
      • Analysis shows that harvested forest has a different composition of species to non-harvested forest.
      • The change in species composition is necessary for ecological processes to continue and is one reason why the jarrah forest is so diverse.
    • The importance of species successions will be the focus of future analysis.
    • Data from the first five years of monitoring have been published in Australian Forestry, and data from 10 years of monitoring are currently being analysed.

    forestcheck graph small
    FORESTCHECK has gathered data on about 3900 species
    Larger Graph

     Related resources

    Progress reports

    Information sheets

    pdfThe FORESTCHECK project: Integrated biodiversity monitoring in jarrah forest274.42 KB
    pdfFORESTCHECK: The effects of silviculture on the structure of jarrah forest stands327.82 KB
    pdfFORESTCHECK: Monitoring soil disturbance caused by timbers harvesting in jarrah forest 283.02 KB
    pdfFORESTCHECK: The response of vascular flora to silviculture in jarrah forest 319.22 KB
    pdfFORESTCHECK: The response of macrofungi to silviculture in jarrah forest333.43 KB
    pdfFORESTCHECK: The response of lichens and bryophytes to silviculture in jarrah forest 387.52 KB
    pdfFORESTCHECK: The response of macro-invertebrates to silviculture in jarrah forest381.56 KB
    pdfFORESTCHECK: The response of birds to silviculture in jarrah forest280.95 KB
    pdfFORESTCHECK: Terrestrial vertebrate associations with fox control and silviculture in jarrah forest 413.15 KB
    pdfHydrological impacts of timber harvesting?99.44 KB
    pdfReducing soil disturbance during timber harvesting242.69 KB
    pdfFire regimes and forest tree health137.25 KB

    Plans
    Related Databases
    • BugBase 
      A database of Parks and Wildlife's Forest Insect Reference Collection, composed mainly of specimens of beetles, butterflies and moths.
    • Florabase
      Provides botanical information on all Western Australian flowering plant families, genera and species. Includes identification tools, photos, maps, a database of botanical literature and (for registered users) collecting details of more than 700,000 vouchered herbarium specimens from across the State.
    • Walpole Wilderness Invertebrate Fire Research Project
      Local volunteers from the Walpole Community and Walpole Nornalup National Parks Association have been trapping and inventorying the litter arthropod species of burnt and long unburnt forest sites in the Nuyts Wilderness. This website records their findings.
    Posters

    Contact

    Dr Lachie McCaw