Detlef and his new female partner have not yet done the wild thing Courtesy of Allwetter Zoo, Münster

And that’s ruffling the feathers of gay activists who believe the zoo is standing in the way of love.

The bromance began in March when Guido and Detlef—a pair of griffon vultures—began nesting together at the Allwetterzoo in Münster, northwest Germany. Just as a straight couple would do, the lovebirds groomed each other and gathered sticks to build their home. They stuck it out through good times and bad—overcoming attempts from other vultures to steal their building materials and food. Apparently homophobia exists in nature, too. (Read about Harry and Pepper, the San Francisco Zoo’s gay penguins.)

Speaking to the Times (of London), the zoo’s curator Dirk Wewers claimed adverse selection explained the love affair.

“They always sat so closely together. They defended their nest from the other vultures. A suitable female was missing and in such a case vultures look for companionship from the next best thing, even if it is a male. Detlef looked for a bird of the opposite sex but settled with Guido.” (Read TIME’s article, “Why Some Animals (And People) Are Gay.”)

Hoping to engineer a heterosexual partnership, zookeepers forcibly separated the pair last week. Guido was transferred 400 miles east to a zoo in the Czech Republic, and replaced in Münster by a Czech female. Neither of the male birds has done the wild thing since the relocation. But, says Wewers, “Detlef is reorienting himself now…There’s still time.”

Gay rights campaigners have already staged one small protest outside of the German zoo. And the German Herald reports that the nation’s blogosphere is alight with anger over the break-up of a happy home in the name of heteronormativity. (Read TIME’s article “The Gay Side of Nature.”)

“This is like in the dark middle ages, forcibly making a creature sexually re-orient itself by tearing its partner from its side,” one blogger wrote.

“While the Roman-catholic church in the arch-conservative area of Münsterland is jubilant, homosexual federations and animal protection organizations from the whole world over are indignant.” (See pictures of Germany’s polar bear celebrity Flocke.)