Two years ago, the National Institute of Health (NIH) decided to retire all but 50 of its 360 research chimpanzees. The amount of research that uses this animal has been declining ever since, with a recent report by Science Magazine suggesting that biomedical research on chimpanzees could come to an end.

This decline is mostly attributed to a 2011 report by the Institute of Medicine, which argued that “alternate research tools have rendered chimpanzees largely unnecessary as research subjects.” The move was followed with the U.S. Fish and Wildlife Service's (FWS) recent legislation that classified all captive chimpanzees as endangered under the Endangered Species Act (ESA). The ruling comes into force on September 14, 2015 and research labs will require a permit for certain activities with chimpanzees. So far, not a single U.S. lab has applied for a permit to conduct invasive research on chimpanzees.

Permits will be needed for any research that constitutes a “take,” or anything that the ESA labels as “harm, harass, kill, injure, etc.” It’s unclear how behavioral research falls under this guideline, and whether routine procedures such as taking blood samples would be considered a take. Researchers also have to prove that the work would benefit the species both in captivity and the wild.

Allyson Bennett, Associate Professor at the University of Wisconsin-Madison who works with non-human primates, and spokesperson for Speaking of Research, tells IFLScience that there is a “critical negative that’s not being well considered.” Mostly, this decline might affect chimpanzee conservation efforts.

“Research is the way we understand the animals and ourselves. This research serves the chimp, it serves the public and the environment. We’re losing an incredibly important and invaluable species,” Bennett explains.

Bennet points to the case of researcher Peter Walsh, who developed conservation vaccines for gorillas and chimpanzees that are also affected by Ebola. While in theory Walsh's work could get a permit, this might not be the case in practice. Walsh previously described the NIH’s decision to wind down research on chimpanzees as a catastrophe for conservation as he suggests a lack of demand will close down many research facilities.

“Walsh made a compelling case that the U.S. is the only place that would be able to do controlled work to test the vaccine before we would use it in wild populations. That’s really important to conservation goals and management of chimpanzees in the wild.”

She says that over the last few decades, laboratory research in the U.S. has contributed fundamental new insight into and understanding of chimpanzee behavior, cognition, psychological processes, biology, and genetics. The NIH has funded primate centers in the U.S. for over 50 years to produce a wide range of studies that have both contributed to human-relevant science and improved chimpanzee care in captivity and in the wild.

“These centers fall under strict federal oversight, external oversight and transparency. When we see NIH support for chimpanzee research decreasing, we’re going to see a change in where the work happens,” Bennet says.

One of the questions Bennett raises is that if the work is happening elsewhere, what does the future of biomedical research look like in U.S.? As the U.S. is the last developed country in which biomedical research on captive apes is still permitted, many other countries have become dependent on the work the U.S. has done.

Bennett predicts that within 10 to 20 years, captive chimpanzees will only be found in zoos in the U.S. A current breeding ban and an aging chimpanzee population suggest that they “won’t be in sanctuaries or research facilities.”

“That limits the opportunities to learn about the animal,” Bennet adds.