The knowledge that platypus can inhabit waterways close
to human settlement should be a source of great pleasure for all Australians.
Unfortunately, planning or management decisions are sometimes taken which
can affect the species adversely in urban areas.
Positioning recreational tracks along
waterways
The construction of walking paths and cycling tracks
along creeks and rivers has been a very positive force in encouraging the
community to appreciate the beauty and value of local waterways.
However, if such paths and tracks are built too close
to the edge of water courses they facilitate access by predators such as
foxes and dogs, and can also contribute to bank erosion. To encourage the
development of an adequate vegetation corridor, paths and tracks should ideally
be located at least 30 metres from the bank. To minimise predator access
and discourage the development of informal trails
down to the water, bridges and viewing platforms are best placed at points
where the water is reliably deep and the banks are relatively steep.
Retaining buffer zones
Urban development should never be allowed to encroach
unreasonably close to the margins of creeks or rivers. To help control
associated environmental problems, it is essential that a buffer strip of
healthy vegetation be maintained between the edge of a waterway and new
developments such as housing or industrial estates, carparks, shops, and
recreational facilities. The reserved strip of land should be wide enough
to support a self-sustaining plant community, including native shrubs and
low-growing vegetation as well as mature specimens of the tree species originally
found in the habitat. Thought should be put into designing (and, over the
longer term, maintaining) a corridor which screens out increased noise and
light levels, restricts access by feral predators and pets, stabilises the
bank and protects it from trampling, traps loose soil and surplus nutrients
arising in adjoining developed areas, provides resting and nesting sites
and protective cover for platypus and other wildlife, and contributes to
a more stable and productive freshwater ecosystem.
Especially if time is required to re-establish a substantial
corridor of native vegetation along the waterway and/or eradicate weeds,
we recommend that the buffer zone be protected by fencing the edge of the
new development. To be most effective, the fence must be built of a durable
material, be tall enough to discourage passage over the top by children and
pets (i.e. in the order of at least 2 metres), and have its lower margin
buried deeply enough to reduce the likelihood that holes are dug below by
rabbits or wombats. Secure fencing will discourage litter being dumped and
unofficial paths being created to the creek or river. In the case of new
housing estates, it will also counter the tendency of suburban landowners
to increase their garden area at the expense of adjoining natural habitats.
Looking at lighting
Bright artificial lights may affect the behaviour or
mortality rate of many wildlife species, including platypus - especially
given that the nocturnal activity pattern shared by most Australian mammals
has probably developed first and foremost as a strategy to avoid detection
by predators. Bright lights that are located near a waterway may also be
a problem for many aquatic insects (the mainstay of the platypus diet) which
emerge from the water at dusk as winged adults to breed and lay eggs.
We therefore recommend that street lights or bright
security lights located within 100 metres of a waterway be designed to minimise
the amount of illumination directed towards the water. Preference should
also be given in such areas to using light globes that produce relatively
small amounts of insect-attracting blue and ultraviolet light (i.e. sodium
vapour or yellow incandescent globes) while avoiding the use of mercury
vapour globes.
Responsible pet ownership
Domestic dogs and cats are both potentially predators
on platypus, with inexperienced juveniles and animals living in shallow
streams especially at risk. Don't let your dogs and cats wander unsupervised
at night - this will help safeguard the welfare of your pets as well as wildlife!
Obey local laws which prohibit the presence of unleashed
pets near lakes, rivers and streams. Even during the day, uncontrolled
dogs and cats can disrupt the natural behaviour of platypus and other native
species occupying such habitats.
Make sure that unwanted pets, including kittens and
puppies, are taken to an animal shelter rather than being dumped in bushland
and left to fend for themselves - this practice is both cruel and environmentally
disastrous.
Reducing water consumption
The natural flow of many streams and rivers has declined
as a result of increasing water consumption by humans, reducing the capacity
of the waterways to support platypus and other animals. Changing a few
of our habits can make an enormous difference to the amount of water we
use, while significantly improving our standard of living at the same time.
For instance, suburban grass lawns demand a great deal of water (and other
resources) for their upkeep - one study has estimated that the average Australian
lawn costs over $2,000 per year to maintain, including the large amount
of time spent mowing, trimming and fertilising the grass. Replacing some
or all of a lawn with indigenous shrubs or ground cover plants that require
less water in summer (when natural flows are most restricted) makes good
economic as well as environmental sense.
What else you can do
It is important that people realise that their individual
actions have a genuine impact, for better or worse, on the long-term survival
of platypus populations.
* Learn more about how you can conserve water in your
home or business, and adopt at least one or two new water-saving practices
each year.
* Help to build awareness of the fact that platypus
are (or should be) living in local lakes, streams and rivers.
* Ensure that local planners and councillors consider
the needs of platypus whenever a new development is proposed near a waterway.
Platypus conservation is not necessarily incompatible with a reasonable
level of development - provided that sensible precautions are taken to protect
(and ideally strengthen) freshwater habitats.
* Support local "Friends" groups and other community
conservation organisations in their efforts to control weeds, plant trees,
pick up litter, and otherwise improve the environmental quality of urban waterways.