October 13, 2025 – Earlier this year, a 51-year-old chimp named Montessa arrived at Chimp Haven, a lush 200-acre sanctuary in Louisiana. For three decades she had undergone painful and invasive experiments in a federal laboratory. Her moment of freedom, which she shared with 20 other retired chimpanzees who finally relocated with her, was decades in the making.

A milestone in our work to end the use of chimpanzees in biomedical research came with our success in securing the full protection of captive chimpanzees under the U.S. Endangered Species Act through a campaign to end the U.S. Fish and Wildlife Service’s “split-listing” designation. This followed our successful push in the late ‘90s for the establishment of a federal sanctuary for chimps owned and supported by the government when t

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