Biodiversity Strategy - Gosford City Council - NSW Government

Grazing and trampling by goats, deer and other domesticated animals may degrade the value of
native bushland. In some instances grazing animals appear to have been deliberately used to
degrade the value of bushland areas, sometimes in preparation for land sale or development.
Overgrazing leads to land degradation as too many hard hoofed animals in one area will
denude areas of all groundcover, leading to soil disturbance and make land less arable. Action
is needed to halt unauthorised and inappropriate clearing and other uses that degrade native
vegetation and to strengthen planning controls to protect key corridors and habitats. Wildlife
corridor linkages need to be identified and protected through strong planning controls. Also
greater enforcement concerning unauthorised activities is required to protect conservation value
lands.
A - 7.3
Weeds
Weeds are plants that are not native to a particular area and that out-compete native species for
their habitat. This results in the displacement of native species that would be naturally found
there. Over time this can result in modified simplistic ecosystems dominated by a handful of
weed species such as Lantana. Weeds can include native species that have become
acclimatised to local conditions. Examples include the Queensland Silver Wattle and Common
Fishbone Fern (native to northern NSW).
Noxious weeds are those listed under the Noxious Weeds Act and attract state
funding for their control. Noxious weeds are generally a threat to the agricultural
industry. Environmental weeds threaten bushland area but are not generally listed
under the Act. Funding for their control may be available through environmental
grants.
Previously weeds have not often been recognised as a serious threat to biodiversity although
this situation may be changing. The Parliamentary Secretary to the Minister for the Environment
and Heritage, Dr Sharman Stone (29/03/04
http://www.deh.gov.au/minister/ps/2004/psmr29mar04.html) identified weeds as being second
only to wholesale land clearing as a cause of biodiversity loss and stated that weeds were
slowly killing the Australian environment.
Potential weeds include winter fruiting plants that produce berries that are easily dispersed by
birds such as currawongs such as Privet and Camphor Laurel. This may result in further
ecological imbalances as certain species are favoured by the food resources available. Weeds
may be ‘sleepers’, that is they take time to become established but have the potential to be a
significant weed problem over the longer term through evolutionary adaptations such as
tolerance to drought, or by being prolific seeders. Plants that are currently popular garden plants
such as Murraya may in time become serious environmental weeds as Privet that was originally
grown as a hedge plant has done.
Transport corridors and waterways may be a source of weeds as well as means of spreading
weed seed and weed propagules. Railway easements and road verges can harbour significant
weed infestations. Creeks, waterways and drainage lines also spread weeds and nutrients,
contributing to weed problems downstream (eg. Crofton Weed, Alligator Weed, Privet, Balloon
Vine and Madiera Vine). Urban runoff adds nutrients to natural areas with resulting changes to
soil pH. Increased nutrients and altered soil pH favour introduced species and lead to increased
weed invasion. These factors result in many watercourses becoming heavily weed infested
(such as with Privet and Camphor Laurel).
There are also a number of aquatic plants that are of concern in Gosford City. One that is
potentially impacting on the biodiversity of Gosford's saltmarshes is the proliferation of Juncus
acutus. This South African rush is very similar to the native Juncus krausii that it displaces.
Biodiversity - Technical Report Page 155