National Association for Biomedical Research Critiques IUCN's Decision on Long-Tailed Macaques

On October 9, 2025, the International Union for Conservation of Nature (IUCN) reaffirmed the endangered status of long-tailed macaques (Macaca fascicularis). This declaration followed a petition submitted by the National Association for Biomedical Research (NABR) back in 2023, challenging IUCN's status classification. The NABR contends that the review by Hansen et al., which formed the basis for IUCN's determination, misrepresents existing scientific data.

According to NABR’s scientific expert group, the lack of comprehensive data and distortion of available information raises significant concerns about the scientific process used by IUCN to arrive at this decision. Dr. Ray Hilborn, a renowned scientist and member of the NABR expert group, voiced disappointment over IUCN's failure to objectively assess the scientific information presented to them. He emphasized that the data's inadequacies and misrepresentations present serious questions regarding how IUCN conducted its evaluation.

These long-tailed macaques are extensively utilized in biomedical research due to their physiological and genetic similarities to humans. Remarkably, five out of the twenty most commonly prescribed drugs have been developed utilizing data from studies involving long-tailed macaques. Their involvement has been vital for advancements in regenerative medicine, immunology, cancer treatment, vaccine development, and pharmacology, notably contributing to the development of a COVID-19 vaccine.

Recently, the National Institutes of Health (NIH) reaffirmed the crucial role of long-tailed macaques in biomedical studies, underscoring their importance in research environments.

Matthew R. Bailey, the president of NABR, expressed his organization’s frustration about IUCN's susceptibility to pressure from animal rights activists, who influence perceptions of long-tailed macaques as an at-risk species. Current scientific evidence clearly indicates that this species is not endangered and is considered invasive in several territories. Bailey mentioned, "IUCN's claim of this species being at risk contradicts their acknowledgment of it as one of the most invasive species in the world. NABR will continue to advocate for sound scientific information to inform policymakers and the public, thereby protecting public health interests and supporting the integrity of scientific inquiry."

Interestingly, long-tailed macaques are cataloged as one of the invasive alien species by the IUCN’s list of the top 100 worst invasive alien species globally. In September 2024, discussions concerning the conservation status of long-tailed macaques and PETA’s involvement in government initiatives were raised during U.S. House Oversight Committee hearings. Testimonies during the hearings revealed how groups like PETA and other animal rights organizations have inappropriately sought to influence government investigations concerning private sectors and foreign governments for political purposes.

Founded in 1979, NABR stands as the sole non-profit 501(c)(6) organization dedicated to fostering a balanced policy on the humane use of animals in biomedical research, education, and testing. Comprising over 340 members, including universities, medical and veterinary colleges, teaching hospitals, pharmaceutical and biotech companies, patient groups, and multiple academic societies, NABR champions humane and responsible animal research for the greater good of both human and animal health globally. For more information about NABR, visit www.nabr.org.

In summary, while IUCN's classification indicates a commitment to preserving species, NABR's critique suggests a need for rigorous investigation into the processes that lead to such declarations, advocating for scientifically supported policies over those influenced by activist agendas.

References

1. Hilborn, R., Smith, D. R. (2023). Is the Long-Tailed Macaque Endangered? American Journal of Primatology, e23590. https://doi.org/10.1002/ajp.23590
2. Hilborn, R., Chaloupka, M. (2025). Assessment of Widely Distributed Primates. American Journal of Primatology (in press).
3. Albrecht, L., et al. (2021). COVID-19 Study Lessons from Non-Human Primate Models. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8402317/
4. IUCN, 100 Worst Invasive Alien Species Worldwide. https://www.iucngisd.org