Cane toads

In 1935, the cane toad (Rhinella marina) was introduced into Queensland to control cane beetles. Unfortunately, cane toads had a much more diverse diet than expected, and these animals soon left the cane farms and have dispersed across the country - to New South Wales, the Northern Territory and Western Australia. They are present in coastal dunes, woodlands, rainforest and freshwater wetlands, and can also adapt to urban areas.

Although non-native, the cane toad is not listed as a species that must be managed in the Biosecurity Act 2014. This is because they have become so well established that eradication is no longer feasible, and consequently, they are considered to be naturalised.

However, Mulgumpin (Moreton Island) remains cane toad free, and is one of only a few locations in coastal Queensland where cane toads are not found. A Commonwealth Threat abatement plan supports the protection of offshore islands to prevent cane toad impacts upon native species, and it specifically identifies Mulgumpin as being a location of importance for preservation.

To keep Mulgumpin cane toad free, Brisbane City Council delivers an educational program for visitors, undertakes eDNA surveys to identify microscopic evidence of cane toads, trials and deploys technologies, and employs cane toad detection dogs to sniff out cane toads that may have hidden in vehicles and camping equipment to make their way to the island.

Appearance

Adults

Cane toads can vary in size, shape, and colour, however there are two key features that can identify a cane toad:

Poison gland on the shoulder
Bony eye ridge meeting in an M shape over the nose

Several other features can be used in addition to the above to confirm that you have the correct identification. This includes:

coloured brown, olive-brown or reddish
thick, leathery skin with warts
small feet, with claw-like un-webbed digits to dig
Visible eardrum between the eye and poison gland.

Don’t mistake a frog for a cane toad

Brisbane is home to several species of frogs that have similar characteristics to a cane toad. It’s important to have the correct identification before you dispose of a cane toad.

When confirming if it’s a cane toad, ensure you can identify the two distinctive characteristics above, along with at least one of the secondary characteristics.

See the Keep cane toads off Moreton Island face sheet for picture references.

Visit the Water Gum website for more information on can toad identification.

Tadpoles

Cane toad tadpoles can be identified by their dark features. They are jet black, not translucent, and their tail is generally the same length as their body. They also tend to swim together in large schools.

Frog tadpoles are generally brown, translucent, and their tails are longer than their body length. They tend to swim individually from each other.

Eggs

Mature female cane toads lay thousands of eggs per season in long, clear gelatinous strands with black eggs. Developing tadpoles appear as a black bead strand.

Problems caused by cane toads

Cane toads are toxic at all stages of life. They cause environmental damage including:

poisoning and killing anything that consumes them (dangerous to birds and reptiles who mistake them for frogs as well as some domestic animals)
eating small reptiles, insects and other amphibians
displacing and out-competing native species for food and resources.

Cane toads also transmit diseases including salmonella. They can cause toxic illness or death to humans if venom is ingested or if their venom enters the eye.

Prevention and control

Being an invasive species, all landowners have a General Biosecurity Obligation (in the Biosecurity Act 2014) to manage cane toads on their land. Even where established, there are tools that can be deployed to reduce the impact and density of cane toads.

Egg removal

To remove eggs, use disposable gloves and:

lift each strand of eggs out of water
lay the eggs in the sun to dry
dispose of them in general waste bins.

Tadpole lures

One of the unique features of cane toads is their response to cane toad toxins.

When placed in water, the poisonous toxin acts as a lure to cane toads and their tadpoles.

Using this natural response, Bufo Tabs are produced using cane toad toxin in a safe to handle block that can be placed in a bucket with a funnel and inserted into a waterbody. These tadpole traps will lure all cane toad tadpoles safely into the bucket where they can be disposed using the same method as for cane toad eggs.

These traps are effective and not harmful to other marine life (including frogs).

Visit the Water Gum website for more information on how to build a tadpole trap, or to order lures.

Adult traps

There are several options of adult cane toad traps that are able to be purchased. These cage traps have water placed inside them, and have a light that lures insects, with the insects luring greedy toads. Where deployed near water, they can be effective in capturing adult toads. New technologies include the incorporation of mating calls, which can increase captures significantly.

Traps will need daily monitoring, and if used in areas where cane toads are established, will need to be deployed with consideration given to disposal, as the method for euthanasia will need to be capable of being delivered for large numbers of animals.

Humane euthanasia

The fridge-freezer method is the most humane method of euthanasia that is currently available for metamorphosized (juvenile or adult) cane toads.

This involves capturing the animal, being careful not to touch it without gloves, andplacing the cane toad in a container before putting it in the fridge. The container should be kept refrigerated for a minimum of 24 hours, which will send the animal into hybination (sleep).

After 24 hours, move the container into your freezer for an additional 24 hours, after which time, they can be disposed of in general waste.

Ensure you wear gloves and exercise caution when handling cane toads.

Cane toads don't climb well or jump high. As a result, cane toads can be prevented from entering areas with as little as garden edge fencing. To be effective, cane toad barriers should be:

around 50 centimetres high
made of moulded plastic or metal – as without webbed toes, cane toads cannot climb smooth surfaces in the same way as a frog.

Note: fencing may also exclude some native wildlife species from the water body.

Keeping Moreton Island cane toad free

Moreton Island is one of Brisbane’s major natural areas. It is one of a few locations in coastal Queensland where cane toads are not established.

To keep Moreton Island cane toad free, check your camping and fishing gear before travelling to reduce the risk that you may accidentally transport cane toads to the island.

When unpacking, vigilance is essential, as every year cane toads try to sneak across with visitors. As camper trailers, utes and vehicles are unpacked, be on the look-out for stow aways, and if you find one, contact the Park Ranger who will ensure it is humanely euthanised.

You can also find and report sightings of cane toads on Moreton Island using Council’s Report it portal.

View a demonstration of the cane toad detection dogs in the video below.

Fact sheet

You can download Council's fact sheet and brochure about cane toads on Moreton Island.

Download the:

More information

To find out more about cane toads, visit the Queensland Government website.

Last updated: 10 September 2024