When Center for Nuclear Security Science and Policy Initiatives (NSSPI) graduate student Jordan Hillis Clark began her work on the Rhisotope Project, an effort to deter rhinoceros poaching using radiation detection techniques, she did not anticipate the level of international attention it would receive. The project was eventually highlighted by the International Atomic Energy Agency (IAEA), which provided technical and financial support, and covered by major media outlets including CNN, BBC, NPR, and The Guardian.

Working under the guidance of Dr. Craig Marianno, NSSPI Deputy Director and associate professor in the Texas A&M University Department of Nuclear Engineering, Clark’s doctoral research focused on evaluating the safety and detectability of radioisotopes embedded in rhinoceros horns. The Rhisotope Project, a collaboration between Texas A&M, the University of the Witwatersrand, Colorado State University, and other partners, aims to reduce poaching by enabling the detection of trafficked horns using existing radiation monitoring systems.
According to Clark, “Incorporating radioactive material as an anti-poaching measure offers dual advantages: it serves as a psychological deterrent due to contamination risks and facilitates the detection of smuggling activities.”

In support of the project, Clark developed a computational model of a rhino head to estimate radiation dose and assess potential biological impacts. Her work helped define conditions under which radioactive material could be introduced without harming the animal while remaining detectable by radiation detection systems. These analyses supported field implementation efforts in South Africa, where treated animals are being monitored to validate the approach.
In parallel with her research, Clark contributed to training activities focused on nuclear security applications supported by the National Nuclear Security Administration’s Nuclear Smuggling Detection and Deterrence (NNSA-NSDD) Office. She assisted with the planning and execution of exercises for the NSDD Science and Engineering Team (SET), which involved various hands-on scenarios at the Texas A&M Engineering Extension Service’s Disaster City facility, as well as workshops on gamma spectrometry for national security. These workshops provided participants from partner countries with instruction and practical experience in radiation detection instrumentation, gamma spectrum analysis, and laboratory and field measurement techniques. She worked with NSSPI and NSDD staff to plan these activities and served as a facilitator for several hands-on training exercises.
“Collaborating and learning from the NSDD is not an everyday opportunity for students,” Clark said. “The experience of watching the NSDD conduct exercises opened my eyes to even more opportunities within the nuclear security enterprise. It was rewarding to make connections and understand more applications that me and my peers can pursue for our future careers.”

Through these NSDD-supported efforts, NSSPI students gain experience working alongside national laboratory staff and international partners while applying technical knowledge in realistic scenarios. As Clark explained, this combination of research and hands-on training helps prepare students for careers in the national laboratories and the broader nuclear security enterprise.
Clark also assisted in preparing and executing responder trainings and exercises for multiple organizations, including Radiological Assistance Program Region 4 (RAP 4), Civil Support Teams (CST), and the IAEA’s School of Radiation Emergency Management and “Train the Trainer” Workshop in Radiation Detection for Caribbean Community Member States. These activities provided experience supporting both domestic and international partners in radiation detection and response.
During her time with NSSPI, Clark helped revive the Texas A&M University Health Physics Society (HPS) chapter and served as its president in 2024. She received the H. Wade Peterson Memorial Award at the 67th annual HPS meeting in Spokane, Washington, in 2022. She also participated in NSSPI’s International Nuclear Facilities Experience program in Japan, where she gained exposure to nuclear fuel cycle facilities and international safeguards practices. In addition, she was invited to the Massachusetts Institute of Technology to present at the Nuclear Energy Agency Global Forum Rising Stars Workshop in Nuclear Education, Science, Technology, and Policy. Clark also completed a summer internship with the detector engineering group at the Nevada Nuclear Security Site, where she worked on coded neutron imaging.
Clark earned her Ph.D. in nuclear engineering from Texas A&M University in the summer of 2025. She has since joined Los Alamos National Laboratory, where she continues to support the NNSA-NSDD mission.