The federal government moved Tuesday to further protect chimpanzees, proposing to change the animals' endangered status and increase oversight of their use in research.
The plan represents the latest in a series of steps taken in the past two years to better safeguard the animals, one of man's closest genetic cousins, and shield them from use in scientific research. Top medical institutions also are changing their stance toward the use of chimpanzees.
The action Tuesday was by the U.S. Fish and Wildlife Service, which is proposing to classify both wild and captive chimpanzees as endangered. Right now, only wild chimpanzees are listed as endangered, while captive chimps are classified as threatened. After being petitioned by animal rights groups, the Fish and Wildlife Service determined that the Endangered Species Act, which governs the classification system, doesn't allow for captive animals to be assigned a separate legal status from their wild counterparts.
Animal rights groups cheered the move. Dr. John J. Pippin of the nonprofit Physicians Committee for Responsible Medicine said he was thrilled.
"Full protection under the Endangered Species Act is long overdue for chimpanzees, our closest living relatives," Pippin said. "The new status is a tremendous change that ends the completely unprotected current status of captive chimpanzees."
The move means that privately owned chimpanzees will now likely be off-limits to invasive experiments, Pippin said.
The proposal is subject to public comment, meaning changes could still be made. If the proposal is finalized, certain activities would require permits, including the import and export of chimpanzees in and out of the U.S.
People who have chimps as pets won't need permits to keep them. A permit would be required to buy a chimpanzee from another state, but not from somebody in your own state.
As for their use in biomedical testing: Activities that could harm or harass a chimpanzee will require permits, and interstate sales of chimpanzee blood, cell lines or tissues will as well. The Fish and Wildlife service said some biomedical research could be permitted through provisions that allowed for experimentation to "enhance the propagation or survival of the affected species." The Fish and Wildlife Service said it would work with the National Institutes of Health, the nation's premier biomedical-research facility, on how to allow continued research on chimpanzees.
In its proposal, the Fish and Wildlife Service said there were about 2,000 chimpanzees in captivity in the U.S., and the latest estimates put the worldwide population of the animals at 300,000 to 430,000. Chimps' numbers are threatened, in part by encroaching human development and by hunting. The capture of chimpanzees for the international pet trade also has been one of the causes of the animals' decline, and the proposal noted that killing a female who has an infant earns twice the income for a hunter: The mother's body is sold in the bush-meat trade and the infant enters the pet trade.
The use of chimpanzees in research has undergone a significant transformation in recent years.
A 2011 special report by the McClatchy Washington Bureau found that science had moved beyond the use of chimps. Researchers say advances in laboratory techniques mean that knowledge once gained only by examining a live animal now can be learned in a petri dish. And an expanding body of evidence shows that chimpanzees don't work as well as the human fill-ins that researchers once hoped they would.
The ethics of animal research also have evolved. What once was commonplace is now controversial, and there's a growing feeling that chimps should be spared the pain and mental anguish of research.
In the past two years, the NIH has moved to curtail the funding of chimpanzee experimentation. In its proposal, the Fish and Wildlife Service noted that while some biomedical research on captive chimpanzees continues in the U.S., "there is a decreasing scientific need for chimpanzee studies due to the emergence of non-chimpanzee models and technologies."
"Chimpanzees have repeatedly proven to be poor models for many areas of human disease research, such as HIV, malaria and other infectious diseases, neuroscience research and cancer," Pippin said.
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