Invertebrates

Invertebrates in KGR occupy the soil and freshwater, live in and around plants, and are most obvious in the inter-tidal zone such as at Long Reef where some species are directly linked to the geology, For example, common sea-urchins (Heliocidaris erythrogramma) drill short burrows in softer rocks, but not in sandstone.

Soil is host to ants, termites, cicada and beetle larvae, spiders, and earthworms. All of which play important roles in soil mixing and aeration and contribute to litter breakdown and nutrient cycling. Smaller species such as nematodes, mites, and springtails are abundant in the litter but are harder to locate and identify.

Australia has about 2,000 species of spiders but numbers in the KGR are unknown. Hunting spiders are the most abundant followed by ambush spiders and then the weavers (web makers), which are divided into the apprentices and the masters.  Spiders can be found in the soil and litter, between rocks, with inconspicuous webs in the vegetation, on and under freshwater pools. In Autumn, a bushwalker in the woodland can be brought to a sudden stop on meeting the large web of the golden orb-weaving spider (Nephila sp.) stretched across the path. Despite its size this spider is harmless but there are about 20 other spiders with fangs and venom strong to harm humans. Only two are potentially lethal; the Sydney funnel-web (Atrax robustus) and the red-back (Latrodextus hasselti). Both can be found in the KGR and it is wise to treat all large spiders with caution.

At least 15 species of butterfly are noted in the Lane Cove catchment with a wonderful range of colours and patterns. The most common species vary from year to year and most have erratic flight and short rest times that are frustrating to photographers. Feeding trails of the scribbly gum moth (Ogmograptis sp.) are highly visible on the bark of the scribbly gum (Eucalyptus haemastoma). Made by the tiny moth larvae chewing through new cambium these trails increase in width every time the larvae moults.

Australia has a surprising 2,500 species of terrestrial gastropods (slugs and snails). The easiest one to find a trace of in the KGR is the red triangle slugs (Triboniophorus graeffei) which leaves a characteristic meandering scalloped trail on smooth-barked eucalypts and sandstone surfaces where they have been grazing on algae.

Finally, there are invertebrates that seek out visitors; ticks (Ixodes holocyclus) are common in dry scrub wherever native animals are present and they can feed on people and dogs. People may become host to leeches (Chtonodbella limbata) in places with moist understory and of course, there are inevitably flies and mosquitoes!