Conservation Physiology and Black Rhinos – How Faeces Are Helping Conserve an Iconic Species

Conservation physiology, according to Dr. Rachel Santymire, is, “really about capturing how wildlife is interacting with its environment…[and] using the animal’s physiology to understand how they are interacting with their environment to better conserve them.”

Dr. Rachel Santymire is now the Director of the Davee Center for Epidemiology and Endocrinology at Lincoln Park Zoo in Chicago, IL. Ten years ago, she was hired to establish a research center to bridge the gap between population biology and veterinary medicine through the study of epidemiology and endocrinology. Through non-invasive research into the basic biology of wildlife, the center’s mission is to uncover the relationship between physiology, behavior, and then environment in order to aid wildlife conservation in captivity and in the wild.

Conservation research, however, was not always Dr. Santymire’s intended path – “I kind of fell into it…I wanted to become a veterinarian because I was really interested in dogs and cats and horses when I was in high school and I thought that if you were interested in animals that’s kind of what you did.” Dr. Santymire began her education at Clemson University in South Carolina in their pre-veterinary/pre-animal science program where she learned a great deal about reproduction in animals.

Shortly afterward, she met Dr. Dave Wildt from the Smithsonian’s National Zoo. “He was an animal scientist who worked with pigs and he had taken those skills and was applying them to endangered species like cheetahs and cloud leopards.” She was hooked by, “…how I could actually use ‘animal science’ to do wildlife conservation.” But it was not strictly the conservation that interested her – it was the physiology. “Obviously there was a conservation aspect, but I was really interested in the reproductive physiology.” So, Dr. Santymire stayed at Clemson to complete her master’s degree and became involved in the zoo field and conservation physiology. She was later hired at the National Zoo and completed her Ph.D. at George Mason University in conjunction with the Smithsonian.

Conservation Efforts in the Field

Dr. Santymire is currently studying the physiology of wild black rhinos (Diceros bicornis bicornis) at Addo Elephant National Park (AENP) in the Eastern Cape of South Africa in order to help conserve their population. She is carrying this work out with Lincoln Park Zoo and in partnership with with Dr. Elizabeth Freeman at George Mason University and the park managers of AENP.

The conservation of black rhinos is difficult because their secretive nature and preference for dense habitats makes them challenging to track and monitor. As a result, little is known about their behavior and physiology. To circumvent the challenge of locating and monitoring rhinos up close, Dr. Santymire and her team have chosen to study what they leave behind – their faeces. This non-invasive approach has facilitated the discovery of new and important aspects of the reproductive physiology of black rhinos in the face of environmental pressures. The Davee Center’s motto sums up this approach succinctly: “If it defecates, we will study it!”

By examining hormones in black rhino faeces, Dr. Santymire and colleagues have been able to explain why two separate AENP (the Addo main Camp and Nyathi) populations differed in their reproductive success. Initially it was noted that in Nyathi rhinos were reproducing almost a whole year faster than those in the Addo main camp – a critical difference when it comes to an endangered species. From their work, it was found that female black rhinos in the Addo section had longer inter-calving periods and were less likely to be pregnant than females in Nyathi. Dr. Santymire and her colleagues suspect this difference has to do with biotic stressors – Addo has more elephants, predators (lions and spotted hyena) and tourists than Nyathi. It’s important to understand how individuals respond to these environmental pressures because it strongly affects their reproductive ability and ultimately the rebound of the population.

Practical Uses

This is all very interesting, but how is this information being used to conserve of black rhino populations? The manager of AENP was involved in all research projects geared towards understanding the physiology of the resident black rhinos. These findings provided park officials important information that has helped them better understand and manage black rhino populations.

Unfortunately, the current poaching crisis and its subsequent safety issues have forced Dr. Santymire to suspend their work in the field. They hope to return to continue their field work, but they are continuing related projects in the laboratory. In light of this poaching epidemic, this work is more essential than ever. If we wish to encourage population growth in the face of exponentially increasing poaching rates, managers must be aware of how different environmental stressors affect reproductive ability of this species.

Conservation Efforts in Captivity

Apart from her work in the field, Dr. Santymire is involved in the management of black rhinos at the Lincoln Park Zoo. Most notably, Dr. Santymire, in conjunction with zoo animal care staff and the Species Survival Plan (SSP) for eastern black rhinos, helped bring about the birth of a male eastern black rhino in 2013. This was particularly significant because rhinos have a miniscule window of time during which conception is possible.

Dr. Santymire worked closely with Lincoln Park Zoo rhino managers to collect daily fecal samples from female Kapuki so they could track her reproductive cycle. Because it takes three days for hormones circulating in the blood to leave the body of a rhino, Dr. Santymire was left behind the rhino’s biological clock.

To thwart this issue, Dr. Santymire also had managers collect daily behavioral data, which she then overlaid the behavioral data with the hormone data from the corresponding day – “And then we looked at what behavior is signaling the female is in estrus – and it actually wasn’t her, the female’s behavior! It was the male’s behavior.”

When Kapuki would come into estrous, male Maku would become more aggressive as he tried to defend the territory around Kapuki. Once these distinctive behaviors were revealed, the animal care staff began introductions when conception was possible. After 13 months, Kapuki became pregnant. But Dr. Santymire’s work did not end there – she continued monitoring Kapuki’s hormones through the daily collection of fecal samples, and was able to give the animal care staff an accurate estimate of when Kapuki would give birth to her son, King.

Photos of Kapuki (top left), Maku (top left), and their son, King (bottom), courtesy of Lincoln Park Zoo.

Photos of Kapuki (top left), Maku (top left), and their son, King (bottom), courtesy of Lincoln Park Zoo.

Advice from a Research Veteran

Dr. Santymire would not be overseeing so much interesting research and helping to orchestrate the conception of rhinos if she had not earned her PhD. When I asked whether she would recommend that students interested in wildlife research or conservation physiology pursue their PhDs, she gave a refreshing answer:

“After obtaining my MS degree, I became a research technician and I work on multiple projects including elephants, black-footed ferrets and cheetah. It was great to be involved with so many species. Besides doing the “grunt” lab work, I was involved with some of the events like artificial inseminations, where we were able to see the animals up close, and going to the field to see wild ferrets. However, I wanted to ask my own questions so I pursued my PhD.

This enabled me to have my own lab and to carry out my own research projects. I also really enjoy mentoring the next generation of students. However, I caution your readers to be careful because sometimes directing scientific programs means more administrative duties and spending less time in the lab and field. I still get out in the field, but it gets difficult with all the duties of a director. Of course there are benefits like higher salaries, but there is more responsibility. So it’s definitely a personal choice that people need to make.”

Dr. Rachel Santymire on the job working with black footed ferrets, Courtesy of Lincoln Park Zoo.

Dr. Rachel Santymire on the job working with black footed ferrets, Courtesy of Lincoln Park Zoo.

Final Words

It is clear from Dr. Santymire’s work that conservation physiology, in the field and in zoos, is important to wildlife conservation efforts. Conservation is a multidimensional issue requiring approaches from many angles, such as veterinary sciences and conservation physiology to the similarly recently developed fields of conservation behavior, psychology and economics – it’s not just about population biology any more!

While these are all excellent take away messages, one of the most encouraging is that Dr. Santymire did not start out with the intention of becoming a conservation physiologist. She took the opportunities that were available to her and pursued her interests wholeheartedly. It’s best to remain open-minded about your career path – not having the career you intended does not mean you will not be successful.

The best career advice to gather from this article is to follow your interests and apply them to worthwhile causes – I’m sure you will not be disappointed.

Career Stories, Careers Advice

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