Stan Honda / AFP - Getty Images file

New York City's Central Park covers 843 acres.

Calling it the largest donation ever to a park in the U.S., New York City on Tuesday announced that hedge fund billionaire John Paulson had donated $100 million to the nonprofit that maintains Central Park.

Mayor Michael Bloomberg joined Paulson and others at a ceremony at the park's Bethesda Fountain Tuesday morning.

"Central Park is the most deserving of all of New York’s cultural institutions," Paulson told reporters. "And I wanted the amount to make a difference. The park is very large, and its endowment is relatively small."

The donation will go to the Central Park Conservancy, which in 1998 took over maintenance of the park's 843 acres.

The park's endowment is at $144 million. Its annual operating budget is around $46 million, and the conservancy provides 85 percent of that.

Half of Paulson's donation will go to the endowment, half to capital improvements.

Paulson has been a member of the conservancy's board since June, the New York Times reported.

With a personal net worth estimated by Forbes at $12 billion, Paulson made his biggest profit in 2007 by betting the U.S. housing market would slump. When it did, triggering the recession, his correct bet netted him an estimated $4 billion.

Last year, however, his main funds had double-digit percent losses from premature bets on a strong economic recovery. 

Paulson, 56, and his family will have a birds-eye view of the improvements -- they have a Fifth Avenue apartment facing the park's east side and overlooking its reservoir, BusinessWeek reported.

Reuters contributed to this report.

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Central Park rape suspect David Mitchell spits at reporters as he walks to the police car after his arrest.

Updated at 7:31 p.m. ET: Police arrested a suspect Thursday in connection with the violent sexual assault of a 73-year-old birdwatcher in Central Park, New York Police Department spokesman Paul Browne said.

The suspect, David Albert Mitchell, 42, was identified by the victim in a lineup at the Special Victims Unit on Thursday afternoon, NBCNewYork.com reported. He was charged with predatory sexual assault, rape, criminal sex act, robbery and assault.

Mitchell said nothing as he walked out of central booking in Manhattan to a police car, only spitting at reporters as he walked past them.

It wasn't immediately known if he had an attorney.

Mitchell was picked up near the park at 77th Street and Amsterdam Avenue by three rookie police officers patrolling the area at about 7:20 p.m., hours after Wednesday's attack, Browne said.

Police initially held Mitchell on a charge of threatening a man inside Central Park on Aug. 20 as they waited to see if the woman could identify him as her attacker in Wednesday's incident.

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The victim in the Aug. 20 incident, a man, told police the suspect threatened him with a large knife inside the park. When police released photos of the suspect while searching for him Wednesday, the male victim recognized him as the man who threatened him several weeks ago.

Mitchell was charged with menacing in connection with the Aug. 20 incident.

Detectives requested a warrant for Mitchell's DNA as well as a warrant to view images on a digital camera memory chip they found on him. He has an extensive criminal record in Virginia and was released in March 2011 after spending about seven years in state prison on a kidnapping charge. He was acquitted of murder and sex assault charges in a separate case in 1989.

It's not clear how long Mitchell has been in New York City. He has no arrests in the city and appears to be homeless, authorities said.

The bird-watching victim in Wednesday's attack told police she had seen her attacker before, and believed he assaulted her near Strawberry Field's Wednesday morning because he was angry she photographed him exposing himself in a more isolated area of the park a week earlier.

The woman told investigators the man asked, "Do you remember me?" before attacking her about 11 a.m. near the park's tranquil Strawberry Fields that serves as a memorial to John Lennon, Police Commissioner Raymond Kelly said at an earlier news conference.

She said he demanded she delete the image before they went their separate ways. Police said that initial encounter was not reported.

On Wednesday, investigators spoke to Eric Ozawa, a college professor and fellow birdwatcher who had called 911, while other officers and detectives swarmed the scene in search of the suspect.

Ozawa, 34, told reporters he was in the park about 11:30 a.m. when he noticed a pair of legs sticking out along the path but thought it was somebody sleeping. As Ozawa got closer, he realized it was a woman lying face down. Her face was badly swollen, she had a black eye and was covered in mulch, he said.

Seth Wenig / AP

Police officers talk near the scene of the alleged rape of a 73-year-old birdwatcher in a heavily wooded section of Central Park in New York, Wednesday.

Still, she appeared "self-possessed and lucid," he said.

Daylight attack 'shocking'
The woman told Ozawa she had been mugged and raped, he said. He immediately called the police.

"It's shocking that it could happen in the park in broad daylight," he said. "That someone could rape somebody in her 70s."

Police blocked off much of the area near West 72nd Street and Central Park West as they hunted for a suspect described as a man in his 40s.

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NYPD via AP

This image taken from surveillance video and provided by the New York City Police Department on Wednesday shows a man believed to have mugged and sexually assaulted a 73-year-old woman in New York's Central Park.

Emily Loubaton, 29, of Brooklyn was in the park on a scavenger hunt that her company had organized.

"I think this is pretty disgusting, and so shocking it would happen on such a beautiful day in such a beautiful park," she said.

Asked if she felt less safe in Central Park, she said: "I'd like to believe that New York City has turned the corner for the better. I mean, this isn't the '70s. But it definitely makes you pause before you walk in."

Strawberry Fields was named after one of the Beatles' best-known songs, "Strawberry Fields Forever." It was officially dedicated in 1985, five years after Mark David Chapman fired five shots outside the Dakota apartment house on Dec. 8, 1980, killing Lennon.

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