BEACON, NY — The annual music festival launched by Pete Seeger more than four decades ago will be scaled back this year as the Hudson River Sloop Clearwater struggles with financial losses, the environmental organization announced Tuesday.

Instead of a two-day music festival, Clearwater will hold a weekend of environmental activism this June 20-21 at Croton Point Park along the Hudson River north of New York City, said Greg Williams, Clearwater’s executive director. Attendance will be limited to about 500 people.

The annual Great Hudson River Revival, billed as the country’s oldest and largest music and environmental festival, has served as a fundraiser for the Sloop Clearwater, a 106-foot-long replica of a Dutch sailing vessel that Seeger, the late folk music artist, launched in 1969.

The sloop has had a prominent role in the cleanup of the Hudson River, as well as educational programs and advocacy of environmental and social justice campaigns.

The festival is held every year on Father’s Day weekend. It was founded in 1966 by Seeger and his wife, Toshi, and has featured artists such as Janis Ian, Arlo Guthrie, Dizzy Gillespie and Indigo Girls. Last year’s festival celebrated the 100th birthday of Seeger, who died in 2014.

Williams said that thousands of people attended last year’s festival, but that the event lost about $190,000, partly due to poor weather.

“It would be irresponsible of Clearwater to move forward with replicating another million-dollar Clearwater Festival in 2020 without having addressed the financial loss we incurred in 2019,” Williams said in a written statement. “We expect these steps, with the public’s ongoing support, will put us in the best position to return with the Revival in 2021.”

The festival was canceled in 2016 so resources could be directed to restoration of the sloop but it returned in 2017.