This is the really important bit of the course so pay attention! If you do everything correctly then you should catch lots of tadpoles. However, there are a couple of small mistakes you can make that will make your trapping activities completely ineffective. So make sure you learn the routine and do everything correctly!
Lures should be stored in a container, at room temperature, out of reach from children and pets. Do not leave them in the sun and do not leave them anywhere where they will overheat. Children should not handle the lures, strictly adults only, and please always wear gloves.
In terms of traps, The Watergum Cane Toads program has evolved significantly over time.
Initially, we instructed people to make their own traps, but this didn’t go so well. We found that poorly constructed traps meant participants had little success with their tadpole trapping and lost faith in the program as a result.
Therefore we decided to take over trap-making ourselves and make it really nice and easy for people to get started straight away. This has worked fairly well for the last few years, however the home-made traps still come with a lot of problems, even when we make them ourselves.
We have now solved this problem with the introduction of our new and improved machine-made trap! The new traps are far more durable than previous models and all the issues experienced with home-made traps have been resolved.
The new traps will be available soon!
When to Trap
First rule of tadpole trapping, only use your trap and lures if you can actually see tadpoles! If you can’t see tadpoles, it’s not worth using one of your precious lures!
The season generally starts around September time so that is when you should start checking for tadpoles. If you can only see one or two tadpoles, they are probably native frogs and not cane toads. Only use your trap when you are sure there is a swarm of cane toad tadpoles to be caught! Wait for ideal conditions to use your trap, using the guide below. Remember, tadpoles will take at least 3 weeks to turn into tiny toads and leave the water, so you have some time to plan your trapping session. Wait until there are lots of tadpoles present to ensure you get the most use out of your lure. The images below show the difference in size between day old tadpoles and 2+ week old tadpoles.
Ideal trap placement is essential for successful trapping. Follow these rules and you can’t go wrong!
Don’t add your lure straight away
Place your trap sideways in the water to allow the inside to fill quicker and then slowly turn upright. Wait for the water to settle before adding your lure. This will allow a nice scent plume to fill your trap and drift slowly out of the funnels, making it really clear to the tadpoles where they need to swim to get to the source of the scent.
Place your trap as close as you can to the tadpoles
Your lure is going to create a scent plume that leads into the trap, through the funnels. Help this process by limiting the distance it needs to cover.
Water depth should be over the top of the funnel spouts but below the lid
DO NOT fully submerge your trap. This will cause the lure scent to leak out of the lid and form a cloud around the trap. This means there is no-longer a clear lure plume leading into the funnels and the tadpoles will have no reason to swim into the trap. If you are using one of our homemade traps, you will need to make sure the water level is below the ventilation holes around the top rim of the trap. If it rains, this may effect the water level so check your trap regularly.
DO NOT place your trap in a moving current
A moving current will carry your lure scent plume away with it and the tadpoles will struggle to find the source. In most dams this won’t be a problem, but if you are placing your trap in a creek or a cascading pool, you need to find a suitable spot where the water is reasonably still. This shouldn’t be difficult as this is where tadpoles like to congregate. In ponds, turn filters and pumps off while trapping, where possible.
Make sure your trap is secure and can’t float away
Each water-body is different and you may opt for a rope, a rock, even a custom built frame to keep your trap in place.
Your Trapping Session
How long does your lure last?
Each lure has 24 hours of water-time and can be used multiple times in this period. You can take it out of the water, let it dry out, and use it again the next day. It will get less effective as the 24 hour period is reached and once it has run out, dispose of it in the bin. Each lure is infused with water-safe green dye which aids the manufacturing process. This will fade after the first use but it doesn’t mean your lure has run out, keep using it until the 24 hour period is up.
How long should you trap for?
This is up to you. Members have reported varying levels of success depending on the nature of their environment. Some report great success over-night, while others prefer short, 2 hour bursts in the heat of the day. You will work out what best suits your situation. Just make sure that you check your trap regularly and keep a tally of those lure-hours.
In cooler temperatures, it is not advisable to use your trap overnight. When conditions are cold, tadpoles loose their appetites, so they are less likely to follow the scent plume into the trap.
DO NOT let tadpoles die in the trap!
Dead tadpoles release a chemical that warns other tadpoles to stay away! Check your trap regularly to avoid this happening. Some members add shade-cloth to keep their trap cool. Some members use a small net to remove tadpoles at regular intervals. If you do have tadpoles die in the trap, end your trapping sessions and thoroughly clean it with hot water and washing-up liquid, rinse and leave to dry in the sun.
DO NOT move your trap
Once you have started your trapping session, refrain from moving your trap as you will disrupt the lure scent plume. The lid enables you to to check and remove the contents of your trap without disturbing it.
Only use one trap at a time
Using two traps can actually work against you as the lure scent plumes can join and confuse the tadpoles. Only those with very large dams should use multiple traps.
Removing Your Trap From the Water
Don’t lose your catch!
When you remove your trap from the water, water will fall out of the funnels and take the tadpoles with it if you’re not careful. (This problem will be resolved with out new machine-made trap!) The best way to avoid this is to have some help. One person cover one of the funnels with a net while the other tips the trap in that direction as they slowly remove the trap from the water. This will ensure that any tadpoles that exit through the funnel will fall into the net. If you are on your own, try using a large tray or bucket, or scoop some of the water out prior to removal so that the water level is below the funnel spouts. Once the water level inside the trap decreases below the funnels, you’re safe! Remove your trap from the water slowly so that the water pressure doesn’t stress the silicone joints and may cause them to fail (This problem will be resolved with our new machine-made trap!). Deposit your catch into a net, sieve or bucket and get ready to record your data!
Be sure to check your trap for bi-catch. Common by-catch includes small fish, which are easy to remove with a net. Uncommon by-catch includes frog tadpoles and eels. Always check and put those ID skills to good use!
Wash your trap after each use
Cane toad tadpoles from one family do not like to mix with cane toad tadpoles from another family. Family groups swarm together and if you see a big group of tadpoles, it is likely they are all siblings from the same clutch. When the family populate the trap they will leave their scent behind. If you fail to wash your trap after each use, the scent of the previous catch will linger on the trap and will deter other tadpoles from entering. Clean your trap with hot water, washing-up liquid and a sponge after each use, particularly the silicone joints, and leave out in the sun to try. If you notice a decline in trap-efficiency, you may find that the scent of past catches has sunk into the silicone joints. This is why its a good idea to re-do your silicone joints every year or so (This problem will be resolved with our new machine-made trap!).
It is really important that you rinse off any soap-suds and leave to dry in the sun, before using your trap again. You don’t want to add any chemicals to the waterways. Native frogs are particularly vulnerable as they absorb substances through their skin, on contact.
Download and Print our Pre-Trapping Checklist and makes sure you give it a once over before each trapping session to make sure you don’t waste your precious lures.
Discussion point: What kind of water body are you planning on using your tadpole trap in?