17/07/2024
Be vigilant folks. We recently found these at Taigum. Nasty little buggers!!
What happens when native ants meet invasive red fire ants? And do baits for invasive fire ants affect native ants? Two questions I’ve been recently asked.
Reply: This question needs context. Invasive red fire ants pose the greatest risk to Australians and Australian biodiversity either have ever faced, with almost all of Australia at risk from this aggressive, destructive invader.
When fire ants spread, they attack, overwhelm and eat any living thing unfortunate enough to be unable to escape by their method of mass attacks, biting and stinging anything edible, anything that threatens their nests, and anything that gets in their way. Livestock are not safe in their pasture, pets are not safe in their enclosures, and humans are not safe in their gardens.
Now we know the context.
When fire ants move in to new territory, they consume the opposition. They attack and eat native ants, eliminating them and their role in the local ecology.
Let’s be clear about fire ant baits. They attract and kill most ant species. When they are used in infested areas, the native ants will most likely already have been eliminated or greatly reduced by fire ant predation. Harm to them has already been done.
1) The impact of baits on native ants (and the environment) are not as large scale, or as long lasting, as the harm done by fire ants.
2) This impact of baits on local ant populations was first studied at 60 invasion sites around Brisbane between 2001-2006. Native ants recover.
They found that most local ant species either increased in number or recorded no change (McNaught et al. 2014).
This suggests that local ants were not affected by repeated applications of broadcast bait.
The National Fire Ant Eradication Programme states: “In addition to fire ants, ants in the genus Pheidole, which include the introduced coastal brown ant, Pheidole megacephala, also reduced in number. The baits we use are registered to treat this species, so this trend was not surprising.
Native black ants and meat ants (Iridomyrmex species) increased their numbers rapidly after fire ants were killed on these sites, meaning that the presence of fire ants negatively impacts their numbers.
Black ants and meat ants are ecologically important ant species that often dominate native ant communities. Their low numbers in the data were caused by the presence of fire ants rather than the baiting.
If native ants took the bait and became affected to the point of killing their queen and the nest, then rapid re-colonisation would occur from outside the treated area.
The presence of fire ants and their potentially devastating ecological impacts far outweigh the impacts on native ants than those caused by our baiting activities”.
Read more about the ‘Long-Term Monitoring Sites in Brisbane’, see:
https://web.archive.org/web/20190220041524id_/http://pdfs.semanticscholar.org/1f24/bc4038ba7a05e301075752e54509078af42f.pdf
Invasive red fire ants are a costly, destructive game changer as any region on Earth living with fire ants knows. It is not just about ants, it is about the whole environment.
This is black and white - there is no grey.
Image: Filming 'Tiny Terrors' at Bellis, Brisbane.
See:
https://www.abc.net.au/gardening/how-to/tiny-terrors/11260608
Jerry Coleby-Williams
Director, Seed Savers Network
Biosecurity Queensland Ambassador
18th July 2024
www.seedsavers.net
