Georgia Southern University biologist helps to develop elephant field test kit
Georgia Southern University biologist Bruce Schulte and Smithsonian National Zoo scientist Elizabeth Freeman are testing a field kit used to monitor the hormone levels of female African elephants in the wild.
Elephants are highly social and intelligent animals that use chemical signals to mediate social and reproductive behavior.
According to Schulte, the kits are yielding important information that will help conservationists more effectively manage both wild and captive elephant populations around the world.
‘These hormone kits have transformed how we study elephants under field conditions,” said Schulte, an associate professor in the University’s Department of Biology. ‘They will also provide proof of whether wild elephants display similar endocrine patterns to zoo animals.
‘By generating physiological data for elephant managers and conservationists, these kits will support elephant conservation programs, with emphasis on intensive management and protection as well as scientific research that supports these actions.”
A member of Georgia Southern’s faculty since 1999, Schulte has spent much of his professional career studying elephants, which are the largest living mammals on earth.
‘Humans feel a strong connection to elephants because of their intelligence, strong family bonds and a lifespan that resembles our own,” said Schulte, who travels to Africa several times each year to conduct his research.
Schulte has been studying elephants in captivity since his post-doctoral work with the late Bets Rasmussen in 1993. In 2002, Schulte was part of a multi-institutional research team that received $842,000 in grant funding from the National Science Foundation to study the ways in which chemical signals influence elephant behavior. That ongoing project concentrates on how these signals may be used to discourage wild elephants from infringing upon villages and crops, thus reducing the number of potentially deadly and destructive confrontations between elephants and man.
Schulte served on the doctoral committee of Freeman, who has been studying the impact of socio-environmental factors on reproduction in zoo elephants since 2000. The long-term collaborations between the two scientists paved the way for the development of the hormone kit, a project that Freeman started in 2006.
The kit is designed to gather data helps scientists gain a better understanding of the reproductive cycle of female elephants. The kits utilize fecal samples to measure the levels of certain types of hormones called progestins.
‘Similar to humans, elephants are presumed to experience menopause, yet no one has proven that hormonally,” Schulte said.
Some research suggests that the cycles of reproductive-aged females within a herd may be affected by the presence or the absence, as the case may be of older, non-reproductive-aged females.
‘In some mammals, dominant females can suppress the estrous cycles of other females,” Schulte said. ‘In other mammals, females synchronize their cycles, aligning their pregnancies and therefore their births. This often occurs in species that live in large herds that are mobile.
‘As far as elephants in captivity are concerned, we don’t know why certain female elephants often the oldest females that play the role of matriarchs’ are not cycling. However, if it is a natural behavior, as many scientists are beginning to suspect, then the goal should be to make sure that the herds in captivity are structured so that most young, reproductively valuable females are cycling and available for breeding.
‘For instance, such behavior might suggest the need for multi-generational captive herds that contain an older, non-reproductive-aged female that could be the non-cycling female, thus allowing reproductive-aged females to cycle normally.
‘These kinds of management changes could possibly maximize reproductive potential within a captive family unit’ without compromising herd stability.”
The kit is currently being validated at Addo Elephant National Park (AENP) in South Africa. Georgia Southern alumna Jordana Meyer is a field technician on the project, which is a collaboration between the University, the Conservation and Research Center of the Smithsonian National Zoological Park, South Africa National Parks, and AENP.
Scientists and students from Nelson Mandela Metropolitan University in Port Elizabeth, South Africa, are also contributing to the project.
‘When the kit is proven to effectively assess hormone activity in free-ranging elephants, we will embark on a multi-year examination of the factors that affect ovarian activity,” Schulte said.
Georgia Southern University, a Carnegie Doctoral/Research University, offers more than 120 degree programs serving nearly 17,000 students. Through eight colleges, the University offers bachelor’s, master’s and doctoral degree programs built on more than a century of academic achievement. The University, one of Georgia’s largest, is a top choice of Georgia’s HOPE scholars and is recognized for its student-centered approach to education. Visit: www.georgiasouthern.edu