Water weeds have been deliberately introduced through the nursery and aquarium plant industry for display in backyard ponds and aquariums. Species such as water hyacinth and cabomba have primarily been spread by humans into our natural waterways.
Boating or fishing in weed infested waterways has also contributed to the spread of water weeds from one site to another. Propellers and anchors can cut plants into fragments and spread them within and between waterbodies. Fragments can spread from an infested waterbody to a weed free waterbody by attaching to watercraft, trailers and fishing equipment. Some weeds can survive considerable time out of water and a single plant fragment can start a new infestation.
View a list of water weeds in NSW.
Aquarium and pond weeds cause major problems if allowed to spread. The following species are declared under the NSW Noxious Weeds Act 1993.
Water weeds can:
The NSW government funds a state weed program targeted specifically at water weeds. This program focuses strongly on the 23 water weed species that are declared under the NSW Noxious Weeds Act 1993. This program assists in delivering community education, awareness and extension programs; provides technical support to key stakeholders; and coordinates state strategies for high priority aquatic weeds.
Water weeds are predominantly spread throughout the river systems flowing along the east coast of NSW. Many western flowing river systems are currently free of major weed infestations. It is therefore the key priority of DPI to ensure that these regional river systems remain free of aquatic weeds. In 2010 we have seen 5 new water weed infestations within the Murrumbidgee, Murray and Warrego river networks. It is vital that people report any suspicious water weed infestation to protect the states water resources from weed invasion.
Members of the public, including fishers, divers and members of local environmental groups, are often the first to discover a new exotic weed or the fact that an existing weed has spread into a new area. This information can be very valuable in helping to manage weed problems.
You can protect our waterways and native fish by helping to stop the introduction and spread of water weeds into new areas by: