Plans to build 25 windmills near a protected forest in southern Puerto Rico are drawing outrage from activists who warn several endangered bird species will be stripped of their pristine habitats.

The wind farm, to be built by the Puerto Rican-based company Windmar to produce electricity, would sit atop three isolated mountains in the coastal town of Guayanilla, home to the sprawling Guanica State Forest, where endangered nightjars and other birds breed and nest.

Windmar president Victor Gonzalez said the project would cover about 15 percent of the 800 acres he owns adjacent to the forest, while the rest of his land remains undeveloped as mandated by the U.S. Fish and Wildlife Service.

The 25 windmills would produce an estimated 120,000 kilowatts a year, enough for 20,000 households in the U.S. Caribbean territory, he said.

But a study by the U.S. agency found the project would destroy several acres of habitat used by the nightjar, a gray robin-size night bird. It said the windmills' spinning turbines would not harm the birds.

Wildlife officials in 2006 ordered Gonzalez to paint the mills' rotator blades and reconstruct trampled bird habitats if his project is eventually permitted, said Marelisa Rivera with the Fish and Wildlife office.

Environmental activists in Puerto Rico, where oil-burning power plants provide most electricity, say the project belongs elsewhere. "This is not a proposal that will benefit Puerto Rico," Luis Silvestre, spokesman for the Puerto Rican Ornithological Society, said on Tuesday.