Swans are worse than chickens, though.
I dunno about worse.
I remember when I was a kid, we lived out in the bush and had a bunch of hens, as well as a couple of roosters. Anyway, most of our chickens were bantams, which are much smaller (and prettier!) than your average chicken, but one day when we were at a market (my parents used to go to markets to buy, restore and sell antique furniture back in the day) someone gave us this gigantic hen, since they couldn't keep her as she'd been digging up their garden or something.
So, Goldy (she came with the name, okay) quickly settled in with the others and our chief rooster, Boss, who had been rescued from a cockfighting ring before we bought him, saw an opportunity. In pretty much the most amazing chicken-related moment ever, this majestic, rather violent rooster with a beautiful crest of gold and green feathers, the leader of the tribe, recruited the newcomer- a big, ugly-looking brown laying hen- and began an absolute reign of terror over the local wildlife.
They worked as a team, Goldy would knock creatures down and pin them to the ground while Boss pecked out their eyes/underbellies and killed them. It was pretty horrifying. People say cats are bad for killing native wildlife, well they never saw these fucking chickens. I was too young to remember all the gory details now, but they slaughtered various marsupials, kookaburras, lizards... all sorts of stuff. Especially interesting is the fact that Boss had another hen which was actually his mate, he just joined up with Goldy to kill things.
We eventually lost all our chickens (there were a freaking lot of them, as well as some ducks) when we moved out of there and rented the property out, unfortunately to people who didn't take much care of the animals. They apparently got out and just wandered off with no-one feeding them. That or they starved and turned on each other.
Personally, I like to imagine that their descendants still roam the land, a terrifying breed of ultra-chickens that slaughter all in their path with their size, ferocity and strangely clever tactics. Those chickens were badass.