TUCSON (KGUN9-TV) - Feral cats: They roam Tucson neighborhoods; tens of thousands of them.
But this weekend Nine On Your Side went behind the scenes of a major effort to trap, neuter and return them to help control the growing population.
It's the biggest production of trap-neuter-return -- or TNR -- the Humane Society of Southern Arizona has ever done.
They set out with the group, "Tucson CARES," to treat up to 50 cats this weekend, targeting a large colony on the west side.
They ended up trapping 82.
Late Saturday night, Tucson CARES set traps to curb the growing population.
"These two little bars here come together and you just basically are holding up with tension until one of the cats steps on the platform," a volunteer explained while setting up a trap.
Not a minute later, we hear a rustling sound, and a cat is caught.
The feral feline is then taken to the car. A volunteer ties a tag on the trap -- yellow to indicate the area it comes from -- so post-op they can return it to its home.
But not every cat that falls for the bait will be taken away.
"This is a tipped cat so this one is coming back out." A tipped ear means this feral cat has already been neutered. She opens the cage and he bolts away into the darkness.
On Sunday, all 82 cats that have been trapped undergo surgery, paid for through grants and donations.
Spayed or neutered -- and an ear tip -- it's back in the trap for the wild cat before they wake up from anesthesia; then back in the wild after a day of rest.
"We were going to see how today went and it went fabulously so I'm sure that we'll reconvene and trouble shoot what worked good what we need to improve upon," said Brandy Burke of the humane society.
She said they definitely plan on doing more TNR operations of this scope in months to come.
But if you take care of a feral cat colony in your neighborhood, you don't have to wait for others to trap the cats for you.
The Humane Society of Southern Arizona has information on how to trap, transport and return feral cats here
There are several programs that will loan you traps so you can take the cats to get neutered. Find out more about these programs here