Containing cane toads takes community help
From the November 2008 edition of Agriculture Today.
Retard the spread
Cane toads are great hitchhikers and everyone in affected areas can help limit their capacity to advance:
- Inspect and wash trucks on and off site, including tyre wells, before loading and after delivery
- Inspect and clean the underside of shipping containers while they are on container trucks
- Inspect and clean pallets, timber and other building supplies before loading and after movements
- Inspect pot plants, mulch and other nursery materials before loading and after movements, eg ti-tree and sugar cane mulch, soil and rock materials
- Locate unloading bays in drier elevated areas away from drains or surface water
- Regularly inspect culverts and drains adjoining unloading facilities, particularly during the October to March breeding season
- Bund unloading areas with a 300 to 500 millimetre low wall of smooth plastic PVC liner, buried about 50-100 mm in the soil and firmly attached to pegs driven into the ground
- Regularly inspect the unloading site and bunding for cane toads
- Remove rubbish or waste in yards and storage areas where cane toads will shelter during the day
- Statutory declaration of freedom from cane toads of products or packaging
- Report incidences of cane toad movements to Department of Environment and Climate Change (Parks and Wildlife)
- Dispose of cane toads humanely
It is possible that cane toad populations occur further down the NSW coast and further west than the current known distribution.
In future, changes in climatic conditions and weather patterns may see toads establish in areas previously considered unsuitable.
Recent events like natural disasters, including floods such as the one on the Far North Coast in January 2008, have provided opportunities for toads to be transported in flood waters and debris to new areas.
Previously, disjunct populations of the pest had been confirmed in NSW as far south as Port Macquarie, although recent surveys and reports from the locals indicate that these have now disappeared.
Research has indicated that cane toads are continuing to spread southwards and westwards in NSW, albeit slowly.
One challenge facing all pest managers is detection of animals when their numbers are low.
That said, NSW has a couple of things in its favour that might slow the spread of cane toads.
The climate is drier than the subtropics of Queensland and the Northern Territory, with unseasonal dry spells, particularly on the Mid North Coast and much colder minimum temperatures.
Unseasonal frosts were also reported to have killed many cane toads on the North Coast over the last two years, though not in numbers significant enough to prevent their spread.
Attempts at containment in the present known areas of population in the subtropical parts of the NSW can only be managed with extensive community support and participation.
Populations occur in the shires of Tweed, Byron, Ballina and Lismore, with separate disjunct populations around Yamba and Brooms Head.
The need for water to breed and survive could slow their spread to some degree - they dehydrate at about the same rate as a wet sponge and must rehydrate every two days.
They tend to avoid heavily vegetated areas and steep banks around water holes.
Providing off stream water to domestic stock, fencing off water supplies and revegetating around farm dams can limit access for breeding.
Horse manure provides an insect feed source at night for cane toads, and is best bagged and removed or sold.
To aid identification, monitoring, control and education, the NSW Department of Environment and Climate Change has released a number of leaflets, including Check your load, Life as a Cane Toad and Frog or Toad?
Contact Philip Gardner, Armidale, (02) 6738 8526, philip.gardner@dpi.nsw.gov.au
