When I first considered where I would travel for a Watson year, I immediately thought of Australia. This continent “down under” has held such an allure for several scientists based on its unique wildlife including the top ten most deadly animals in the world. Despite these impressive venoms and hostilities, wildlife here is quite fragile. Millions of years of evolution on an isolated continent has made Australian wildlife sensitive to invasions from other animals and plants. Introduced species like the famous Cane Toad have had horrible impacts on wildlife as they have survived essentially predator-free in the wild. This lack of predation paired with their generalist diet has allowed Cane Toads to spread from their originally introduced habitat of sugar cane farms and diet of cane beetles to local forests and a broader diet of native insects. While competing with native species for food, Cane Toads have also killed several varieties of snakes which fall victim to the toad’s toxic secretions. This competition between native and invasive species can drive native species out of a habitat or into extinction!
While the Cane Toads are famous examples of an invasive species, many invasives are much smaller, particularly the insects which can sneakily be transferred via potted plants and green waste. One infamous insect for doing just that is the Electric Ant (Wasmannia auropunctata) in tropical North Queensland.
Named for their shockingly painful sting, Electric Ants are known to invade an area and kill off surrounding insects, particularly other species of ants. Even though these ants are tiny (1-1.5mm long) their sting and social behavior makes them a powerful force that can eradicate an area of its native wildlife. These ants are originally from Central and South America and thought to have arrived in Australia 10 years ago. These ants are most commonly spread by people when they share plants from one neighborhood to the next or by the ants’ hollow wooden nests naturally being moved by flood waters during the rainy season. So they’re here in Australia and they’re causing a ruckus – what do we do?
Thankfully the government cares about these native disturbances and the Biosecurity of Queensland deals with invasive species like these Electric ants. Similar to exterminators, Biosecurity teams manage and try to eradicate many types of invasive animals from insects (Electric Ants, Yellow Crazy Ants, Fire Ants, and the Asian Honey Bee) to mammals (Feral Pigs, Rabbits, and Foxes). For each of these species, there is typically an allocated team used to capture, treat, and study the invasive animal in order to apply targeted eradication. The Electric Ant team that I got to work with can be broken into four different sections: detection, treatment, identification, and coordination.
Tom Lawton is in charge of a unique way of tracking down these tiny ants. He uses the heightened scent tracking of dogs. Ofira, Eden and Quest are three specially trained Labrador retrievers who can detect the pheromone trails that Electric Ants leave behind.
When I first worked with Tom, I had to control my impulses to pet and play with these adorable dogs because they are strictly trained to detect Electric Ants. These dogs have been bred and raised to detect certain scents, in this case the pheromone of Electric Ants. In order to maintain their abilities to detect the ants, I helped Tom upkeep some of this training. First we hid a few hides in different spots Electric Ants might occur on a site. Each hide is made of a piece of fabric coated with the Electric Ant pheromone which is collected in the lab. We then took the dogs through a site and rewarded them with play (fetching and playing tug with a fabric dollie) if they successfully detected each hide or a real instance of Electric Ants.
These dogs are used to first detect Electric Ants, then return to a site after a few chemical treatments in order to verify that the ants have been eradicated. The positive association of finding the ants and play, which I helped Tom maintain, has set the dogs up to want to find the ants at each site that we take them to, making them valuable tools in finding Electric Ants. For the few sites I visited with the dogs we found two positive instances of Electric Ants and the dogs seemed very good at working to find the ants so long as Tom guided them through a site.
While the dogs are a valuable resource, they are a limited one. That’s why the Electric Ant field team: Albert, Georgy, and Nick are a few of the people there to survey and treat properties for Electric Ants. I joined the team on a few occasions to survey for Electric Ants using a simple method to catch ants: meat. Similar to how you might catch a human, the team places a bit of sausage on the end of a stick with a marker flag, leaves it for an hour, then returns to find the chunk of meat crawling with ants.
This simple set-up is very cost effective given the limited resources for programs like the Electric Ant Biosecurity. All ants have foragers which are sometimes able to find our food sources in a few minutes. After an hour, the hundreds of ants covering the sausage allow us to get a glimpse of what’s in the area. These meat flags are set out every 5 meters, then if we find something, we mark the area with GPS coordinates and take a vial sample to further document and identify the ants in the lab.
Once a population of Electric Ants are detected in an area, three rounds of treatment, a food-coated poison, are disbursed within a 50 meter perimeter of the spotting. Each treatment round is separated by a month and followed up with team surveying or the sniffer dogs. The treatment itself cannot be used under wet conditions as it dissociates with water and should be picked up by the ants within a couple of days after being disbursed. Thankfully this poison has proved successful in eradicating Electric Ant populations so far, but further research into different methods of treatment are currently being researched.
Tash spends her time in the lab, “nerding out on ants.” Tash’s scientific expertise is used to identify the ants to species under a microscope, design new inexpensive methodology of detecting ants, documenting aspects of Electric Ant biology and physiology, and creating new forms of poisonous treatment to eradicate the populations.
In all of her free time, Tash taught me how to identify some of the commonly found ant species including Tetramorium, a genus of ant commonly mistaken for Electric Ants (Wasmannia auropunctata), and other invasive ants like the Yellow Crazy Ant (Anoplolepis gracilipes). It was fascinating to see these creatures under the microscope and learn new terminology for their body segments. Spending time in the lab also felt refreshing as I had the resources to see differentiating characteristics of the ants and read about their biology and distributions.
While Tash now works as the main scientist for Electric Ant eradication, she surprisingly got her degree in marine biology. Tash came to a career change once she met the lack of jobs in marine biology and soon started using her scientific experience in field work with Queensland Biosecurity. While she seems to really enjoy the unexpected outcome, she’s lucky to have found a job using her skills in biological research.
With all the downfalls of having invasive species like Electric Ants, their presence provides a plethora of jobs for scientists like Tash, who have studied a certain field of biology, but not managed to find work in that specific area. Albert, of the field team also didn’t expect to work with ants and received a degree in marine biology and aquaculture. Like Tash, Albert had difficulty securing a job in his field, but soon found himself studying Asian Honey Bees, then Electric Ants in the lab. While out in the field, his interest in the ants allowed him to name the species and common name for each ant we saw, showing that he enjoyed where he had ended up.
Finally, what team works without a great coach? Gary Morton makes all of this effort possible and was my original contact for volunteering with Biosecurity Queensland. He manages the whole team to make sure each site is treated repeatedly and surveys are conducted thoroughly. I was happy to meet Gary and have the opportunity to work with BQ on all the complex methodology required for eradicating Electric Ants.
Biosecurity was not originally part of my project design as managing and eradicating invasive insects was a somewhat novel thought to me. As an aspiring entomologist and insect enthusiast, I spend most of my time studying the benefits of insects. Its important for me to get away from my positive bias and consider how large populations of insects can become invasive though. Introduced species can result in the decline of other insect populations and the deterioration of local habitats, leaving no room for things to be appreciated. The eradication of these ants is paired with some guilt though as we kill several animals in the process of restoring native habitats. Small insect lives may be easily taken, but large mammals are killed for Biosecurity programs too which I find equally upsetting. Hopefully programs like Biosecurity Queensland will spare us from having to exterminate so many species in the future as BQ educates communities on the repercussions of bringing in non-native wildlife and carelessly moving green waste.
These ants are terribly small, but can be thought of as red gold. Their vibrant colors and aggressive stings make them easy to identify and the team at Biosecurity Queensland do their job best when people call in.
Report suspect ants in Queensland by calling 13 25 23!