Humane euthanasia of Cane Toads

You’re keen to make a positive difference to the environment and control Cane Toads (Rhinella marina), but what do you do with them after? There are many ways to kill a Cane Toad, and Watergum recommends using the most humane method available to you. After all, it’s important to remember Cane Toads were introduced to Australia by humans and the individual toad does not deserve to be treated inhumanely. Scientific understanding of humane euthanasia of toads has changed over the years and our behaviour must reflect that.

 At Watergum we recommend using the stepped hypothermia (or fridge/freezer) method to humanely euthanise Cane Toads of all life stages. This is in line with the current best practice for humane euthanasia of Cane Toads, as per RSCPA Guidelines.

Stepped hypothermia involves cooling the toads in the fridge for 24-48 hours. This puts the Cane Toads in torpor, a natural amphibian state similar to hibernation, which switches off their pain receptors. The toads can then be transferred to the freezer for a further 24-48 hours to euthanise them through freezing. 

Read on for detailed instructions for stepped hypothermia, tips and tricks, and how to responsibly dispose of your toads after they have been euthanised.


Stepped hypothermia instructions

Transfer your toads from your toad busting bucket into a container that will fit into your fridge. Make sure it is leak proof and has a lid to prevent Cane Toad escapees. 

Tip: If you toad bust regularly, we recommend considering purchasing a cheap fridge/freezer second hand and place in your garage. You can also have dedicated Cane Toad containers, with air holes drilled into the lid. 

Place your container of toads into the fridge and leave them for 24-48 hours. The exact length of time depends on the volume of toads you have collected and the efficiency of your fridge. For one or two toads, less time may suffice.

During this period of cooling, the toads will slip peacefully into torpor, which is a semi-comatose state, similar to hibernation. When in torpor, Cane Toads are still alive but are unable to feel pain. This means that when they are frozen, they do not feel any pain and simply slip away.

Studies show that when Cane Toads are frozen straight away they experience the pain caused by ice crystals forming in their veins, which can be significant.

Remove your Cane Toads from the fridge, checking quickly that they are in a comatose state. Transfer the toads to the freezer for a further 24-48 hours to euthanise the toads.

Tip: it’s easiest to dispose of frozen toads in the container they are frozen in, so it can be helpful to transfer your comatose toads into a different container or bad. Keep this in mind how you will be disposing of the toads as well. If you are composting the toads, consider a cardboard box or compostable bag. 

Disposing of Cane Toads responsibly

Studies show that Cane Toads remain toxic for some time after death, as the bufotoxin in their paratoid glands does not break down easily in some environments. This means it’s important to responsibly dispose of euthanised Cane Toads and not leave them in the environment, where they can still pose a threat to wildlife and pets.

Here are a few ways you can safely and responsibly dispose of euthanised Cane Toads:

  • Compost: why not put your toads to good use in compost production! In a hot compost system, the toxin will break down quickly in, making Cane Toads similar to other meat scraps. Cane Toad toxin is not dangerous for worms and other insects which reside in your compost system. However, it is important to protect other animals from your decomposing toads.
  • Household bin: Cane Toads can be put in your regular curbside bin for council collection. Different councils have different rules around what can be put in the bins, so check with your area whether it can go in your red or green bin. 
  • Burial: Cane Toad toxin will also break down when buried. If this is an option for you, bury the toads at least 50cm deep to prevent animals from digging them up. 


Why Does Watergum Recommend the Cooling and Freezing Method?

The research to support the declaration of this method being humane is available here and was conducted in 2015. This research monitored body temperatures and the brain activity of cane toads throughout cooling and freezing which shows that they slip into a coma-like state (called torpor) during the cooling period which inhibits brain activity and prevents their brain from recognising the pain experienced from ice crystals forming in their veins which occurs during freezing. This confirms that cooling and then freezing is a humane method of euthanasia.

Controversially, many organisations follow these research guidelines which are out of date. In this document, the most recent research cited for the cooling and freezing method was conducted in 1999 and it was deemed inconclusive (and therefore not recommended) due to the inability to understand the effects of cooling and whether or not they were inhumane. Instead, this paper recommends chemical treatment (despite it being confirmed as inhumane during the study), decapitation and CO2 exposure.

The following points iterate why Watergum does not recommend these methods.

Chemical Treatment

  • This method is proven to be inhumane,

In the UOW trials, after being sprayed according to the manufacturers instructions, toads exhibited a range of behaviours consistent with distress. These included limbflicking, urination and blepharospasm and avoidance of the spray which included crawling and hopping movements and attempted burrowing in the corner of the container. After a few minutes some toads developed ataxia, and most stopped moving and lay with their chins down until death. The ventral skin also turned red and the average time to death was 19 minutes (range from 5 to 36 minutes).’


  • If cane toads are not contained before they are treated, they will hop away and later die in the environment. This means their toxic bodies, in addition to the applied chemicals, will remain exposed in the environment.
  • The application of chemicals means that the toads will be unsuitable for lure production. Toads killed with chemicals can not be used for tadpole lure production as the lures are placed in water and we can not add chemicals to the waterway.

Stunning and Decapitation

  • Large margin for error and improper execution leading to inhuman torture of cane toads and possible injury of general public.
  • Unsuitable for children; risk of improper delivery and injury. There is also a risk of this method being poorly communicated to children and them learning that it is okay to torture animals as a result.
  • Method leaves toad toxin in the environment. Bashing and decapitating toads can rupture the parotoid glands resulting in the toxin being splattered into the environment where it still presents a danger to pets and wildlife. If a dog comes along and licks toxin from the floor its life will be in danger.
  • Method makes toads unsuitable for lure production. The method can rupture and destroy the parotoid gland which is the part we use to make tadpole lures.

Carbon Dioxide for 4+ hours

  • Not suitable for the general public. While more humane than most methods, this method is not practical or safe for use by the general public.