REDSTONE — If you organize a field trip to hear elk bugle, how sure can you be that they’ll cooperate?

That’s what some participants wanted to know last week when the Roaring Fork Conservancy invited the public to hear the majestic animals sound off in the Filoha Meadows north of Redstone.

Truth be told, organizers admitted, they couldn’t make any guarantees. They were just going from past experience that the critters have been known to make their music around dusk this time of year.

“You just never know with nature, and that’s just how it goes,” said Tim O’Keefe, the conservancy’s education director.

Luckily, Kim Peterson of Aspen had played it safe. When she invited her parents, Bill and Phyllis Peterson, of upstate New York, to join her at the conservancy event, she made no promises except one.

“I promised them dinner afterwards,” she said.

Conservancy executive director Rick Lofaro wasn’t optimistic about an hour into the program, when he pulled a bugling device and tried to call out to any elk hiding in the brush on the hillside across the meadows.

“I hate to say, ‘Boy, you should have been here last year,’” Lofaro said apologetically to the more than 20 people who patiently waited in a semi-circle around him, bundled up against the increasing cold at sunset.

But at that very moment his listeners sprung to life.

“There’s one right over there!” one person cried.

“Yeah, two of them!” said another.

An adult elk followed by a smaller one appeared across the valley, heading north along an old railroad right of way running through the property.

“It looks like a single cow with a calf,” Lofaro said.

Then came a squeaking noise — or kind of a bark, as Lofaro described it. It apparently came from the cow elk.

“She’s a little confused, probably irritated, not sure what’s going on,” Lofaro said.

His bugling may have summoned the elk, but now they appeared to be trying to size up what they were seeing and smelling across the field.

“I think they’ve got us figured out,” someone said.

Lofaro also provided a G-rated elk sex education course, centered around bulls for whom bugling is just part of a fall rutting ritual that also includes facing off with other males for the right to reproduce.

This is the time of year when bulls engage in shoving matches with each other, antler to antler.

“All this is about male posturing,” Lofaro said, directing his comment with a smile to knowing female listeners.

The loser usually just skulks off, although occasionally bulls can end up locking antlers or goring other bulls to death. Their weapons are massive racks that are the fastest-growing animal tissue on earth, adding as much as a half-inch of size in a day, Lofaro said.

The bulls also will urinate on themselves and wallow in mud during the rut. And they don’t do much eating or sleeping, which leaves them in weak condition going into winter, Lofaro said.

“They are just enraged with testosterone and the only thing that is on their mind is mating,” he said.

Although no bugling was heard, the Petersons weren’t complaining as they headed back to their car and to the dinner to which Kim had promised to treat her parents.

Said Bill Peterson, “I might have to chip in a little bit because the elk showed up.”

Kathy Small of Carbondale said she was surprised at the noise she heard the cow elk emit.

“They don’t sound like what I expected,” she said. “They’re more like a bird.