A couple of new skyscrapers have already cast huge shadows on Central Park, and the greenspace's advocates say they are worried that this vertical trend will drive people away.

Hundreds packed a meeting held by Manhattan's Community Board 5 on Wednesday night to speak out against the developers of One57, which is set to be the tallest residential building in the city at 75 floors when it opens this year.

Although the skyscraper -- like the other buildings under construction causing the shadows -- was approved as of right, residents, community leaders and others say the developers have been insensitive to their needs and to park visitors.

"If the shadow happens to fall when they are there ... their time is 100% darkened," said Warren St. John, an author and midtown resident who has been spearheading efforts to combat the shadow problem. "Is it really worth that for 400 expensive apartments?"

Along with One57, there are five other buildings, including the Nordstrom Tower, the Steinway Tower, 432 Park Avenue and the MoMA Tower, that are either in construction or in the planning stages near Central Park South that are causing the shadows, which St. John said are at their worst between fall and early spring.

Representatives for the Extell development group, which is building One57 and the Nordstrom, didn't return messages for comment but CEO Gary Barnett told those who attended Wednesday's meeting that the building's slender frame and seasonal changes wouldn't make the shadows a serious problem.

"[The shadow] will only be for a few minutes," he said, according to reports.

Avid park users, however, said there is no substitute for heading to their favorite spot when it is bright in the middle of the day.

"The beauty of Central Park is not being in the city. To get the city more in the park is not a good thing. Sunny days in the park are amazing," said Giuseppe Santochirico, 23, of Astoria.

Layla Law-Gisiko, the chair of Community Board 5's Sunshine Task Force, formed to address the issue, said although the condos will create more jobs and homes for the neighborhood, the shadowed park will make midtown less enticing.

"The difference in temperature in the sunlight and one in the shadow is 20 degrees. Just imagine where you are now, imagine if you dropped the temperature by 20 degrees? You would move," she said.

City Councilman Dan Garodnick, who represents the area and was at Wednesday's meeting with other elected officials, said the city needs to rethink the zoning rules that allow these skyscrapers to go up without any input.

"We need to have a conversation about whether we need to plan more effectively and whether there is real harm that is created when we don't," he said.

St. John, who said he and other advocates wouldn't rule out using litigation to combat the shadows, encouraged more people to speak out against the developers. He noted Jackie Kennedy's famous umbrella protest, which helped to keep the Time Warner Center from reaching its original 63-story height.