After two people tried to commit suicide by going over Niagara Falls in two days, local media were asking questions about the falls, including:

What could enable a person to survive a plunge?

Are suicide attempts from the falls on the rise?

Is a coming high-wire stunt walk over the falls encouraging the suicide attempts?

On Monday, a man plunged 180 feet over the Horseshoe Falls on the Canadian side of the Niagara River. He's now in a Hamilton, Ontario, hospital recovering from injuries that include several broken ribs, a collapsed lung and gashes to his head and shoulders, according to a report in the Buffalo News.

He was pulled to safety by emergency crews after collapsing in waist-deep water, according to a report from CNN affiliate WGRZ in Buffalo.

He is only the fourth person to survive a plunge over the Horseshoe Falls, historian Paul Gromosiak told the News.

The others include a 30-year-old Canadian man in 2009, a Michigan man in 2003 and a 7-year-old boy in 1960, according to the news reports.

The Toronto Star reports that thousands of people have gone over the falls, especially in the 19th and 20th centuries, and asks why the known survivor cases are predominantly recent.

The paper points out that the three most recent survivors went over the railing on the Canadian side near the Table Rock House tourist building. From there, the Niagara River's 25 mph current pushed them over the falls.

Some have speculated that the men could have been pushed away from rocks at the base of the falls by a cushion of water, or that winds whipped up the crashing water, according to the Star.

The late Wesley Hill, a Niagara Falls expert, said in 2006 that the dynamics of the falls change based on the amount of water hydro companies take from the upper Niagara River, the Star reported.

But a man who has investigated the three most recent falls survivor cases isn't certain of any constant among them.

"The Niagara River is completely unpredictable," Niagara Parks Police Sgt. Chris Gallagher told the Star.

What is predictable is that the falls will attract people attempting suicide.

While the man in Monday's plunge survived, another person who went over the American portion of Niagara Falls on Tuesday apparently did not. A body has not been recovered, according to local media reports.

New York State Parks Police said Tuesday's suicide on the American Falls was the fourth this year, slightly ahead of a pace that usually sees nine suicides a year from the American side, according to the Buffalo News.

"We're running a little high," Lt. Patrick B. Moriarty of the State Parks Police told the News.

About 20 to 30 people commit suicide from both sides of the Niagara a year, according to the report.

Police usually don't publicize the suicides, Inspector Paul Forcier of the Niagara Parks Police on the Canadian side told the St. Catherine's Standard.

But a planned June stunt is bringing fresh publicity to Niagara Falls this year and has some questioning whether it is giving impetus to suicide attempts.

Renowned high-wire walker Nik Wallenda has announced he will attempt to walk a tightrope over Niagara Falls on June 15.

Wallenda told the News that the stunt should be encouraging anything but suicide.

"I'm doing the impossible, which is what a lot of people feel they can't do because they're depressed. Me making it across the wire and living shows people that they can achieve anything," the News quotes Wallenda as saying.

Wallenda will walk a 2-inch cable attached to massive cranes on each side of the falls, about 1,800 feet across, and 200 feet up from the bottom of the gorge. The crossing should take about 30 to 40 minutes and is planned to take place in early evening.

The last person to cross the gorge on a wire was James Hardy in 1896, but Wallenda said he will be the first to cross directly over the waterfall.

Psychologists disagree over whether the Wallenda stunt has any connection to suicides, according to the Buffalo News report.

"It's something else that kind of gets the falls out there, kind of plants a seed in people's minds," Timothy M. Osberg, a clinical psychologist and professor of psychology at Niagara University, told the News.

Steven L. Dubovsky, chairman of the department of psychiatry at the University at Buffalo, doesn't see any connection.

"It might have just reminded people that the falls are there. I doubt it would make people want to jump into the falls," the News quoted Dubovsky as saying.

Visitors to the falls on Tuesday told the Standard they didn't think anything could be done to make the tourist attraction safer.

"There are already signs posted telling people not to climb over the railings. Having more police or higher railings would just spoil it for everyone else. People will still climb over. People always do silly things,” the Standard quotes Stephen Moore, a British tourist, as saying.

“You can patrol these areas and try to make them safer, but at the end of the day, things happen. One way or another, they do,” Rich Inge, a tourist from Scotland, told the Standard.

Park police on both sides of the river are a bit more upbeat. They tell CNN affiliate WVIB that they've talked more people out of suicide at the falls than those who have actually gone through with it.

Suicide emergency phones on both sides of the river have made a difference, according to the report.

And anyone who suspects that someone they know is considering suicide of any kind should try to get them to talk, Mary McConnell of Jewish Family Service told WVIB.

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