2015-01-12 General Committee Agenda Attachment 1 to Item 7 Pest Management Plan 2015-2019

3. Pest impacts in Noosa

Pests of our waterways

Aquarium and pond weeds have been introduced into waterways in a number of ways
(including from human activities). For example aquatic weeds can be introduced to a new
water body via vessels, trailers and fishing equipment. Introduced weeds continue to spread
as a result of flooding, movement of water fowl and water based activities.

Of particular concern in Noosa waterways are salvinia (Salvinia spp.), cabomba (Cabomba
caroliniana), dense waterweed (Egeria densa), yellow waterlily (Nymphaea mexicana) and
hygrophila (Hygrophila costata). These weeds grow aggressively and can dramatically alter
environmental and physicochemical conditions and interfere with ecological processes. This
can have devastating effects on native flora and fauna such as the Australian lungfish,
platypus and freshwater turtles.

Aquatic weeds can detrimentally affect recreational and aesthetic values of water bodies.
Heavy infestations make boating and swimming difficult and can also be dangerous to
children and animals if the weeds look like solid ground. In addition submerged aquatic
weeds such as cabomba (Cabomba caroliniana) can cause swimmers to become entangled
in the stems of the weed. Management of infestations in constructed water bodies requires a
regular maintenance program including the use of bulk aquatic weed harvesters at
considerable cost to asset managers. In many instances, once infestation occurs eradication
is almost impossible.

Aquatic pest animals, such as the red-eared slider turtle (Trachemys scripta elegans), can
aggressively out-compete native species for food, basking and nesting sites. They prey on
native species such as aquatic reptiles, frogs, fish, crustaceans and insects and have the
potential to carry diseases and parasites that can infect native fauna.




                                Salvinia (Salvinia molesta)

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