Guillaume Grange recently told Jezebel about the unsettling birds featured in "The Lighthouse," which were green-screened into the movie.

Regardless of where your feelings lie on writer/director Robert Eggers’ disturbed buddy movie from hell “The Lighthouse,” one thing’s for certain: you won’t walk out unscathed by the powerful performances of the birds on display.

Throughout the film, which finds Robert Pattinson and Willem Dafoe stuck together as mad lighthouse keepers on a New England island in the late 19th century, seagulls peck and pry them, representing the maw of death always nibbling at the edges of sanity. Jezebel’s Rich Juzwiak recently spoke to Guillaume Grange, the French animal trainer who wrangled those seagulls, and Grange said these birds were particularly sensitive.

“Seagulls are not very brave, and they’re very fragile. Their wings are very thin. They always worry about everything,” he told Jezebel, adding, “If something worries them even slightly, they regurgitate all the food out. You always have to be very careful with them.” The three birds used throughout the movie are called Johnny, Lady, and the Tramp, and according to Grange, “they will not come and cuddle.”

Grange said Robert Pattinson and Willem Dafoe never encountered the birds, which were shot in a London studio on a green screen.

“Like The Lighthouse, the whole setup was made to avoid stress on the animals. They had breaks. They filmed in a big area,” Grange said. “The crew was minimized. We restricted the movement of the people and the camera when the birds were out. All that is to make sure the animals were not stressed. If they’re not stressed, they don’t mind. You open the crate, they come out. They do everything they have to do, and they go back. They’re happy to return to their crate because there are treats. I’m not going to say that they like it, but they don’t mind it.”

Grange said in order to evoke the necessary performances from the birds, “We threw them some food from far away, and they tried to catch it. Then, we wait a bit. We had to reward behavior and bring them towards opening the beak. So we’d fake throwing something to catch, and when they start the beak movement, we’d reward that.”

In an IndieWire conversation earlier this season with the film’s production designer Craig Lathrop, he said, “We shot everything on Cape Forchu, and we used a puppet stand-in for the actors to interact with on location. Then, in post, we went to London and built some small sets and set pieces and redid the action with the trained seagulls, who were composited into the scenes.”

“The Lighthouse” is currently in theaters.

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