A new weapon in the war on invasive toads

[Music]

cane toads

are relentless invaders

native to central america cane toads

were transported

to sugar cane growing regions of the

world early last century

in the hope they would eat and eradicate

beetles that were devastating sugarcane

crops

this cane toad experiment held the

promise

of a cheap permanent and

everlasting solution to a commercial

problem

the experiment failed spectacularly

cane toads showed no interest in the

beatles

whatsoever instead

they launched a global invasion of

epic proportion cane toads reproduce

at an astonishing rate they eat

just about everything and they are

highly poisonous

across all life stages eggs

tadpoles adults poisoning and killing

virtually every potential predator

the release of just 100 adult cane toads

in australia

a mere 80 years ago led to the current

situation

where hundreds of millions

of poisonous toads now occupy

millions of square kilometres of

australia devastating

native species as they advance across

the nation

cane toads poison and kill lizards

even large goannas they even kill

crocodiles

cane toads poison and kill snakes

including some of the most venomous in

the animal kingdom

even top tier predators are not immune

to cane toads

cane toads poison and kill furry native

species

such as the northern australian qual and

other furry friends

like dogs and cats

for many years the only option

for controlling cane toad numbers was to

hand capture

of adult toads known as toad busting

despite dispatching many tens of

thousands of adult toads

toad busting alone is not the answer

each new generation of toad replenishes

and builds on the last and the invasion

continues

unabated in 2010

time magazine placed the cane toad in

the top

three invasive species in the world

cane toads truly are the borg of the

animal kingdom

and unfortunately at times it seems as

if

resistance is futile we set out

to develop a new cane toad control

solution

inspired by nature and capable of

operating

in parallel with toad busting

we targeted a cane toad life stage

that had previously been deemed

untouchable

the tadpole cane toad tadpoles are

highly distinctive

and easy to spot emerging as black

swarms of many thousands in the shallows

creeks dams and backyard ponds when the

weather

is wet and warm when it comes to finding

cane toad tadpoles we know

exactly when and where to look

and what to look for that toad tadpoles

had not been targeted previously

due to the fact that they are almost

impossible to catch by hand

they’re far too many and they are far

too agile

any attempt at hand netting risks

disturbing

fragile aquatic ecosystems and harming

native species some 2500 years ago

a chinese general wrote the supreme

art of war is to subdue the enemy

without fighting

sound advice if

only we could subbu

subdue towed tadpoles without fighting

and without turning fragile aquatic

ecosystems into battlefields

but how ecologists had observed

that cane-toed tadpoles can

hunt and eat the eggs of other female

toads

there’s a number of possible reasons for

this

tadpoles may be hungry and the eggs are

a nutritious snack

the tadpoles may be staking a

territorial claim

by eliminating genetic competition

or the tadpoles could be repurposing

the poison of the eggs to their own

benefit

more importantly it was also observed

that toad tadpoles successfully hunt

even in murky water with zero visibility

regardless of why tadpoles eat eggs

the more important question was how do

tadpoles find eggs they can’t even see

we discovered that toad padpoles

are drawn to a chemical attractant that

is released

by toad eggs we isolated

and identified this attractant this was

a eureka moment

but before we could use the attractant

to control tadpole behavior

to our advantage we first had to

dramatically increase our supplies

we knew we could extract the attractant

from dead adult toads but we would need

a whole lot of dead toads the call went

out

our bring out your dead appeal

worked and we received

hundreds then thousands of dead

toad busted toads these were processed

in our lab

using an approach that was part csi part

survivor

and part myth busters

put simply we used a giant stainless

steel

blender

to make toad smoothies

from which we extracted large amounts of

tadpole attractant

next we needed a way to deliver the

attractant

the local pet store provided the answer

in the form of air stones

small porous stones about the size of a

dice

once painted with attractant these

stones became

tadpole baits or what we like to call

bufo tabs

finally we went to the local hardware

store

to buy the materials to build a basic

funnel trap

these consist of a simple plastic box

with two plastic funnels inserted and

glued

into opposite ends funnel traps are

cheap

and easy to make we were ready our

theory was

if we placed a bufo tab in a funnel trap

near a swarm of tadpoles the tadpoles

would detect

and follow the attractants sent into the

trap

the theory worked when placed in the

shallows

where tadpoles congregate a single bufo

tab

in a funnel trap attracted and trapped

several thousand poisonous towed

tadpoles

in a couple of hours

as a bonus the attractant is highly

specific

to towed tadpoles and doesn’t attract

frog tadpoles

once trapped the toad tadpoles could be

harvested

humanely euthanized and disposed of

safely

to take the battle to the toad we

created

the cane toad challenge a not-for-profit

community engagement and citizen science

initiative

we provide free baits

and teach the public how to make and use

their own traps

it’s early days but our tadpole trappers

have already removed over a million

poisonous towed tadpoles from local

waterways

we may have started locally but our plan

is to go national

and then global so

join us trap tadpoles

and turn back the toad invasion thank

you

you