Biodiversity Strategy - Gosford City Council - NSW Government

Other studies have considered the diet of domestic and feral cats. Results indicate that diet will
be impacted by the habitat in which the animal is predating. Coman and Brunner (1972) as
quoted by Robertson reported that 44% of the diet of feral cats in forest in Victoria was of native
mammals. However, a study in Canberra found that 63% of all prey was the introduced house
mouse and black rat whilst native species comprised only 0.7% of the diet (Barratt 1997 as
quoted by Robertson). For areas adjoining native bushland predation may therefore be
significant where native species are already in decline and many species are considered to be
at risk of extinction.
The impact of domestic dogs in bushland areas is also a consideration for biodiversity. Dog
faeces cause pollution of waterways and add nutrients to the soil that may favour weed species.
Dog barking and scent can also scare away native species. Dogs also attack and kill native
species such as wallabies and can cause them to spontaneously abort young. Dog barking and
scent can also deter native animals and have been known to cause spontaneous abortions in
wallabies. Dogs may also frighten native species and result in them leaving their young
unprotected. A press release for NPWS (14/10/05) states that domestic dogs let off leashes
outside of designated tracks at reserves in
Hornsby have killed wallabies, bandicoots, possums, reptiles and possibly lyrebirds. "Wallaby
deaths have been reported at Mt. Colah, Westleigh, Berowra and Hornsby Heights and other
fauna are getting mauled regularly across the park ," she said. "These incidences have been
reported by rangers as well as by bushwalkers and concerned park neighbours.
http://www3.environment.nsw.gov.au/npws.nsf/Content/dec_media_051014_01
Dogs are considered a significant threat to koalas, it is estimated that between1,000 to 2,000
koalas are killed across Australia each year by dogs. (Australian Koala Foundation webpage
http://www.savethekoala.com/index.html). Koalas may be killed by even a quick bite or from
trauma or infection. As Koalas come down to the ground and move around at night-time
keeping dogs indoors and not allowing them to roam would protect Koalas where they are
known to occur such as at Pearl Beach and Umina Beach near reserve areas.
A - 7.7
Human Interactions with Native Species
Many people reported via the wildlife survey that they liked to feed the birds and possums that
visit their gardens. Whilst this practice encourages the wildlife to be "friendlier" it can make them
too dependent on a regular food source from humans. This can lead to an inadequate diet, and
the added sugar to the bird’s diet may cause beaks to rot. Feeding birds can also cause overbreeding,
resulting in nests becoming disease carriers. Over-breeding also has implications
when a particular species dominates an area, for example in urban areas Currawong numbers
have rapidly increased, severely impacting upon smaller native bird species such as wrens
which are disappearing.
Some native species (such as Currawongs, Magpies and Noisy Miners) are becoming more
common in urban areas at the expense of other native species as a result of adapting more
readily to the urban environment. Some birds such as Corellas may not have previously existed
in urban areas (notes from pest conference).
Other aggressive or nuisance native species (such as Magpies, Currawongs and Plovers in the
nesting season) can cause issues for people, especially when the birds are nesting and can
become a nuisance by swooping passerbys. It is thought that feeding may encourage some
birds such as magpies to become more aggressive during nesting time. Council receives many
complaints from residents during the nesting season and is requested to destroy nuisance birds.
Cruelty to animals was also considered by many respondents to the wildlife survey to be an
important issue for Council. Issues included destruction of bird eggs, deliberate hunting of
native species, disturbance of nesting birds and ducklings, and it was noted that this was often
done by children.
Biodiversity - Technical Report Page 159