A decade after Halifax scrapped a controversial cat bylaw, the idea may be clawing its way back onto the agenda at Regional Council.

A collection of prominent groups is pushing for the re-introduction of the bylaw in Halifax, in part to protect scores of birds who fall victim to stray and roaming cats in the city every year.

David Currie is the president of the Nova Scotia Bird Society and is temporarily switching from being a hobbyist to a lobbyist to help protect the feathered creatures he's studied for so long.

“We have these global issues with birds,” Currie said. “They're declining everywhere. We're seeing 90 per cent in some species.”

Along with climate change, poisons, and pollution, experts say scores of birds fall victim every year to cats, both domestic and feral.

“We need to kind of find ways to reduce the number of deaths from birds because they're part of our environment -- and they're a very important part of our environment,” Currie said.

It’s enough of an issue for the Ecology Action Centre (EAC) to climb on board, urging the city to look at the bigger picture.

In a presentation they’ve been making to community councils, the EAC said some estimates suggest between 1.7 million and 4.1 million birds die that way in Halifax every year. This number is calculated from national averages gathered in a 2013 study.

Veronica Sherwood is a volunteer with the EAC and says their involvement shouldn’t be construed as an attack on cats.

“I think there's a perception that any conservation groups that are interested in this issue are vilifying cats,” Sherwood said. “That's not at all what we're trying to do.”

Many of the city's stray and feral cats wind up at the SPCA's trap-neuter-return recovery centre, especially since the municipality started funding the program a couple of years ago.

After much debate, council passed a cat bylaw back in 2007, but changed its mind and pulled it about six-months later.

The proposed law is drawing some skepticism from some surprising places.

Because the SPCA’s spay-and-neuter program has been so successful, the agency isn't particularly supportive of a renewed effort to register and restrict the movement of cats in Halifax because there are far fewer of them around.

“We've done over 17,000 surgeries since our clinic opened,” says Heather Woodin of the SPCA. “So every cat coming from the SPCA is spayed or neutered.”

Currie says a study eight years ago said there were 60,000 feral cats in Halifax.

“We still have that similar number,” Currie said. “That doesn't seem to be going down. Even with all that work."

Woodin disputes that number and says it has dropped sharply in the last two years, thanks to the funding from the city.

"We've seen a drastic decline in the numbers of stray and feral cats,” Woodin says.

Sherwood says 17 of 20 large municipalities across the country have similar legislation.

Throughout its history, the EAC has often led the way on conservation issues.

“Honestly, this is another example where the Ecology Action Centre is in a situation, looking at a conservation-issue, that is an uncomfortable and challenging issue,” says Sherwood.

With files from CTV Atlantic’s Bruce Frisko.