Feral chicken are known in several places. They can be pretty successful and have been signaled as threats to ecosystems and crops in archipelagos like Hawaii and Bermuda.
But I've thinking about Brasil: Given the sheer amount of chicken being bread there, the presence of the Amazon rainforest, which has a similar climate to whence jungle fowls, the chicken's ancestors come; and its already fragilized ecosystem, isn't there a specific risk there ?
So far, I've seen no South American country listed as famous for feral chicken presence .
But hypothetically, if a few millions of fowls escaped a massive Brasilian farm and swarmed the Amazon; what could happen ?
Would they quickly die off, due to having lost adaptations to wildlife, having an insufficient ratio of roosters and facing many predators ?
Would they outcompete one or two local bird species and steal their niche, but otherwise fit fine in the food chain without further disrupting the ecosystem?
Or would it spell a great ecological catastrophy ?
The jaguar and anaconda population would increase for a few generations, but it would balance it out after a while.
Why do you think feral chickens are a concern? Most chicken farms in Brazil are much farther from the Amazon, the deforestation land is mostly used to grow soy for animal feed.
No particular reason, chicken, ecological disasters and Brasil are just three things that have been popping in and out of my mind lately, it was only a matter of time until they combined.
The jaguar and anaconda population would increase for a few generations, but it would balance it out after a while
But would chicken still have a place in this new balance? I mean, tigers and pythons haven't hunted the jungle fowls to extinction, nor have jaguars and anacondas done so to the unrelated, yet-
similar tinamu...