Anthropogenic global warming occurs more rapidly in the Arctic than in any other region on the planet. Scientists are observing a widespread decline in the amount of sea ice, as well as novel patterns regarding how the ice is breaking and re-freezing due to greenhouse gas emissions (Stirling & Derocher, 2012). The ramifications are especially troublesome for sea ice-dependent species like polar bears that utilize this resource for foraging and sea ice denning. According to Polar Bears International, there are 20,000 to 25,000 polar bears left in the wild. A multitude of studies have documented adverse reactions within the species from a rapid loss of sea ice. Studies show deteriorations in body size, lower reproductive rates, decreases in population sizes, higher mortality rates, altered migration patterns, and a shift in overall distribution of the species (Fischbach et al. 2007; Rode et al. 2010; Derocher et al. 2011). If these current trends endure, it is projected that two-thirds of the remaining polar bears will vanish within the next forty years. We are bearing witness to an entire species actively fading into extinction.
Current polar bear conservation measures are predicated on the notion that an appropriate habitat both exists and is being proactively guarded. Researchers are working tirelessly to avoid a total annihilation, but this animal is notoriously difficult to study in the wild. An unforgiving harsh environment and the excessive funding needed to conduct studies in the field are just a few of the challenges that scientists face. The only certainty is the dire path that we are walking! One study conducted by biologists associated with the U.S. Geological Survey (USGS) yielded data that demonstrated that a global failure to reduce the release of atmospheric pollutants in conjunction with the burning of fossil fuels will hasten the melting of the sea ice that is so paramount to polar bear survival. So how can we learn more about a species that is problematic to observe in a naturalistic environment and appeal to the masses to alter daily behavior? The answer to both can be found within zoos!
Fortunately zoological institutions serve as an invaluable resource in bridging the gap. Zoo ambassadors are praised for their ability to connect people with animals in meaningful ways. There is no substitute for looking an animal directly in the eye and observing a species up-close. This engages the general public and provokes mankind to get involved. In the instance of the polar bear, zoos are able to educate on effective strategies for reducing one’s carbon footprint. Zoos are exceptional at teaching how small every day actions can lead to dramatic changes. Through the development of a collective movement, we can lower greenhouse gas emissions. This is the primary step in protecting sea ice.
Photo used with permission from Hova Najarian, The Oregon Zoo
The Oregon Zoo is home to twin polar bears named Conrad and Tasul. They were born on December 1, 1984, at the Riverbanks Zoo in Columbia, South Carolina. In 2011, these siblings gained international attention by becoming the first polar bears in the world to voluntarily donate blood. This accomplishment is a revolutionary advancement in animal welfare. Historically, animals of this caliber would require tranquilization. Unlike big cats, polar bears cannot provide blood samples through the tail. Instead, the tops of the paws must be utilized. Avoiding sedation eliminates stress on the animal and avoids the inherent risks that are associated with sedatives. The Oregon Zoo was able to quantify this claim by analyzing blood levels of glucose and Creatine Kinase. Both are known to spike during stress. During the study, the team found that the voluntarily drawn blood samples yielded lower levels of both compared to blood draws from an anesthetized animal. Voluntary blood draws are a product of years of training, bonding, and custom training modules.
These siblings quickly notoriety as special animal ambassadors, and attracted the attention of Dr. Karyn Rode. She serves as a scientist with the U.S. Geological Survey’s Polar Bear Team and contacted the zoo for assistance with their Changing Artic Ecosystems research. The Oregon Zoo was happy to oblige and embraces the motto that “everything we learn here, is applied out there”. Ringed seals are a primary staple in the polar bear diet, but access to this prey is minimized with the decline of the Artic sea ice. Displacement from preferred habitats ultimately shifts feeding patterns within a species. Dr. Rode wanted to comprehend how polar bears are responding to this change. Dr. Rode and her team are developing a method for tracing the chemical composition of prey within a polar bear. Their objective is to observe what the bears have been eating, and the estimated timing of those meals. The polar bears residing at the Oregon Zoo were able to provide blood and hair samples in a controlled environment. Furthermore, she was able to closely monitor the animals’ diet consistently, thus producing reliable and dependable data. This allowed the team to create a more precise formula for tracing chemical composition. Variables in the original calculations were refined while observing these animal ambassadors. During the study, Conrad and Tasul were presented with a terrestrial pre-trial diet and a marine trial diet. The keepers coined the project the Surf and Turf Experiment. The results of the study did not support the original hypothesis. Dr. Rhode initially believed that blood could indicate what a polar bear consumed over the past one or two months. Instead, the data collected from the Oregon Zoo suggested that the samples could date back up to six months or longer. Conrad and Tasul experienced a novel variety of food and the husbandry team notated the curiosity and enrichment that ensued. Simultaneously, the scientists were able to collect vital data to apply in wild populations. The belief is that the findings from the Oregon Zoo study will allow decades of archived blood samples from wild polar bears to be analyzed accurately in hopes of determining how diets are changing in response to the decline of sea ice. For the first time ever, the patterns can be decoded in a scientific manner.
Tasul’s contributions to conserving her wild relatives does not end with the Surf and Turf Experiment. She is also paving the way for researchers to understand and track polar bear movement. Tasul was outfitted with a special collar containing an accelerometer. It is able to create a digital fingerprint of the polar bear’s behavior, as it monitors every day behaviors such as walking, sleeping, swimming, and eating. These behaviors are transmitted into electronic signals and matched by recorded videos to create a chart of the animal’s movement. Researchers are striving to calibrate these signals and place similar devices on wild polar bears in the Artic. This will allow a non-invasive method for monitoring an animal’s behavior through remote access, eliminating the need for direct observation. This is a viable solution to the challenges presented in the field. Each collar is designed to possess a quick-release mechanism so scientists can remotely remove the collar from the polar bear and safely retrieve the data. The intention is to study how polar bears are responding to the displacement arising from the melting sea ice. In order to best conserve polar bears in the wild, scientists must first understand the implications of the climate change.
Photo used with permission from Hova Najarian, The Oregon Zoo
The Oregon Zoo is advancing our scientific understanding of how climate change is impacting polar bears. By partnering with lead scientists at the USGS we are gaining tremendous insight into how to best conserve this species. Conrad and Tasul are unlocking the secrets on how wild polar bears are able to adapt to changes in their food supply. Through their participation, these animal ambassadors allow scientists to accurately analyze decades of data. Furthermore, these animals are pioneering innovative technology that allows scientists to accurately study wild populations from a remote perspective. We cannot protect that which we fail to understand. Zoological facilities like the Oregon Zoo offer unprecedented advancements in conserving their wild counterparts