Analyzing Hormone Patterns of Male Polar Bears (Ursus maritimus) In Human Care Under Different Social Conditions

Dylan McCart, MSc Student York University, Canadian Polar Bear Habitat
Suzanne MacDonald, Ph.D. York University
Erin Curry, Ph.D.  The Center for Conservation and Research of Endangered Wildlife

Project Summary

Polar bears (Ursus maritimus) display seasonal variations in hormone production, however no studies have explored the variables that influence those hormones in males.  Wild male polar bears have been known to aggregate in groupings during the summer months, without the competition for food or mates. During this time of the year, low levels of testosterone are characteristic compared to breeding season, when high levels are documented.

Testosterone has been shown to alter behaviours and aggression levels in other species, and the same may be true in polar bears. If the presence of female polar bears is a variable that influences male hormone levels, human care facilities would have the ability to influence aggressive behaviour by altering housing conditions for their bears. Having that ability could increase the welfare standards and behavioral management for polar bears in human care.

In this study, fecal testosterone metabolites will be analyzed from seven male polar bears housed in five different facilities across North America. An estimated 500 samples will be collected during breeding (March) and non-breeding (September) season. Fecal testosterone metabolites of four males housed with females will then be compared to three housed in the absence of females.

To date, all fecal samples have been collected and roughly 300 of those samples have been dried and analyzed. All data analysis was completed at the Center for Conservation and Research of Endangered Wildlife Endocrinology Laboratory, in Cincinnati, Ohio. When possible, one additional training exchange will be planned to analyze the remaining samples.

Currently, there are 28 bears residing in facilities across North America that may benefit from the results of this study, potentially leading to the improvement of housing conditions for all polar bears in human care. These data will also help us to better understand interactions between polar bears in- and ex-situ, and the endocrinology that might affect their behaviours.

The grant awarded by IBA for this study funded specific training and the sharing of necessary data that will contribute to the improvement of housing standards of polar bears housed in human care, on a global level. This grant will ultimately assist in better understanding polar bear endocrinology and contribute to conservation efforts for this species.

Evaluating the metabolic rate of sloth bears (Melursus ursinus) in their natural range.

Zachary David, Old Dominion University, USA
Dr. John Whiteman, Old Dominion University, USA
Dr. Yaduraj Khadpekar, Wildlife SOS, India
Megan Owen, Institute of Conservation Research, San Diego Zoo
Barbara Durrant, Institute of Conservation Research, San Diego Zoo
Kartick Satyanarayan, Wildlife SOS
Cheeta Seshamanai, Wildlife SOS

Project Summary

“Metabolic rate (MR) is a fundamental property that reflects the total energy demand for all aspects of organismal function, from immune performance to reproduction. As a result, understanding MR is a key aspect of bear conservation; for example, the high field metabolic rate (FMR) of polar bears (Ursus maritimus) makes them particularly vulnerable to the loss of on-ice hunting opportunities, while the relatively low FMR of giant pandas (Ailuropoda melanoleuca) has been used to estimate the food resources required (i.e. bamboo forest area) to support recovering populations.

Resting metabolic rate (RMR) is a measurement of the total amount of energy necessary for self-maintenance and therefore is an essential component of FMR. Sloth bears (Melursus ursinus) are thought to have among the lowest RMR in Ursidae; for example, it has been measured to be 55% of the value for polar bears.  Sloth bear’s low RMR may result from their myrmecophagous diet, which is thought to be associated with adaptations for this low-energy food source. However, sloth bear RMR has thus far only been measured in two captive-born individuals of the Sri Lankan subspecies (M. ursinus inornatus) housed at a zoo in Florida, USA, well outside of their natural range. This subspecies is thought to be smaller and with thinner fur than the mainland subspecies (M. ursinus ursinus). Thus, it is unclear if low RMR is a species-wide trait, and whether it occurs for individuals within their natural range. Using positive reinforcement, the sloth bears will be trained by husbandry personnel to rest in a metabolic chamber for 20-30 minutes, and gas analyzers will quantify the amount of O2 consumed and CO2 produced to determine RMR.

This project will be a collaboration between my home research lab (with my advisor, Dr. John Whiteman, at Old Dominion University in Virginia, USA) and Dr. Yaduraj Khadpekar at the Agra Bear Rescue Facility (ABRF), operated by Wildlife SOS (WSOS) in Uttar Pradesh, India. Using the funds from the IBA Experience & Exchange Grant, I will visit ABRF for 4 weeks to collect RMR data on sloth bears and to train Dr. Khadpekar on respirometry techniques for assessing RMR. Travel to India for this project would not have been possible without the financial support of IBA.”

Testing the potential for using haematophagous leeches and dung beetles as sources of eDNA to detect sun bear (Helarctos malayanus) presence and possibly identify individuals.

Sandeep Sharma, J.F. Blumenbach Institute of Zoology and Anthropology, Georg-August-Universität, Göttingen, Germany
Dr. Shyamala Ratnayeke, Department of Biological Sciences, Sunway University, Malaysia

Project Summary

You can help wildlife biologists and their important work to strengthen our  understanding of bears and protect bear habitat. Donate to the IBA Bear Conservation Fund today.

Make a Donation