Department of Parks adn Wildlife

Monitoring biodiversity in jarrah forests

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 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:
    Coral vine - Photo © Parks and Wildlife

    Why is FORESTCHECK special?

    In addition, FORESTCHECK:

    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:

    What areas are being monitored?

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

  • 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.

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

    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:

    FORESTCHECK researchers use a variety of methods to monitor biodiversity.

    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.

    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.



    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


    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.

    Results and research

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

    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

    Related Databases


    Dr Lachie McCaw