UPDATED 08/18/11 9:32 a.m.

CHICAGO (CBS) — Nearly two dozen dead geese have been found at two Chicago parks this week and officials were trying to figure out what killed them.

Warnings have been posted at McKinley Park at 2210 W. Pershing Rd. and nearby McGuane Park at 2910 S. Poplar Av. after the dead geese were found at the two parks this week.

LISTEN: WBBM Newsradio’s Regine Schlesinger reports

As CBS 2’s Derrick Blakley reports, it’s a mystery that’s baffled park visitors and park supervisors alike.

Three dead geese were found in a pond at McGuane Park on Monday.

On Tuesday, 10 dead geese were found in the lagoon at McKinley Park and on Wednesday, as many as 10 more dead birds were found there.

The Chicago Park District dispatched cleanup crews to collect the dead birds on Wednesday.

Lagoon maintenance worker Lorenzo Torres said he’s never seen so many dead geese at the park at one time.

“We find once in a while, like once a month and that’s it,” he said. “Maybe a total, maybe five geeses a year.”

Animal Care and Control officials planned to test the birds to pinpoint the cause of the death and to rule out poisoning. But a specialist told the Chicago Sun-Times it was likely a disease such as avian botulism.

Geese create a lot of solid waste and, to some, that makes them more nuisance than asset.

“A lot of people in the neighborhood think there’s so many geese sometimes it’s a pain.” McKinley Park neighborhood resident Daniel Tierney said. “My mom actually said it would be nice if they could do something, like get some of the geese out of here, because it wasn’t always this many geese.”

But even if the geese are a victim of what you might call “fowl play,” other water birds don’t seem to be affected, such as ducks and herons that were at McKinley Park on Wednesday.

Still, the Park District wasn’t taking any chances, posting warning notices to keep dogs off the grass while they’re investigating the geese deaths.

For the young people who hang out here, it was tough to understand why anyone would want to harm a harmless bird.

“To the people here, the geese don’t really bother them. They seem to make up the park,” Jose Carrasco said.

It might be a few days before tests come back on the dead birds. In the meantime, the Park District planned to keep a close watch on the parks to see if the number of dead geese continues to mount.

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