Physiological Limits to Hibernation in Large Mammals: Energetics, Body Composition, and Sleep in Black Bears (SGER)

首席研究员将利用一个意想不到的机会来研究冬眠黑熊（Ursus americanus）的冬眠行为、生理学和神经生物学。阿拉斯加渔猎局将提供两只刚刚进入冬眠的“麻烦”熊。这些熊将被销毁，因为它们有危害人类的历史。首席研究员有室外人工洞穴和初步研究表明，大型哺乳动物冬眠与小型冬眠动物（如北极地松鼠，Spennophilus parryii）相比，通过非常不同的生理机制来节省能量。例如，熊大大降低了它们的代谢率，六个月不禁食。它们的体温只会下降3-5摄氏度（而地松鼠会下降40摄氏度）。他们几乎一直处于慢波睡眠状态。首席研究员将使用最先进的遥测技术来测量这些变量，这使他们能够持续监测在自然条件下冬眠六个月的无系黑熊的体温、脑电波、心电图和耗氧量。现在有一个意想不到的机会将这些测量扩展到可能怀孕的雌性身上。这种冬眠生理学从未在冬眠的熊身上进行过研究，它们会怀孕、分娩和哺育后代。首席研究员将与Oivind Toien博士合作，他曾在挪威极地研究所工作。Toien博士对这项研究至关重要，因为他在呼吸测量和遥测方面的专业知识。

AbstractOPP-00-76039Barnes The Principal Investigator will take advantage of an unexpected opportunity for investigating hibernation behavior, physiology, and neurobiology in hibernating black bears, Ursus americanus. The Alaska Department of Fish and Game will provide two "trouble" bears that are just entering hibernation. These bears would be destroyed because they have a history of endangering people.The Principal Investigator has outdoor artificial dens and preliminary that suggests that large mammalian hibernators achieve energy savings with very different physiological mechanisms than do small hibernators, such as arctic ground squirrels, Spennophilus parryii. For example, bears substantially reduce their metabolic rate and do not fast for six months. They achieve this with only a 3-5oC reduction in body temperature (versus a 40 oC decline in ground squirrels). They also remain almost continuously in slow-wave sleep. The Principal Investigator will measure these variables using state-of-the-art telemetry, which allows them to continuously monitor body temperatures, brain waves, EKG, and rates of oxygen consumption in untethered black bears hibernating in natural conditions for six months. There is now an unexpected opportunity to extend these measurements to a female that is likely to be pregnant. This hibernation physiology has never been studied in a hibernating bear that will gestate, give birth, and nurse an offspring.The Principal Investigator will collaborate with Dr. Oivind Toien, previously with the Norsk Polar Institute. Dr. Toien is critical to the study because of his expertise in respirometry and telemetry.