CHAPTER 7 – Polar Bear

摘要: The polar bear is the largest of extant bears. Polar bears occur in most ice-covered seas Northern Hemisphere, including coastal waters Bering, Chukchi, and Beaufort seas. population has grown for nearly 25 years perhaps near carrying capacity. Growth occurred despite dramatic increases numbers people expansion hydrocarbon developments Sea region during same period. Maternal denning, phase life cycle which they are vulnerable, widely scattered remote areas on land pack-ice. Human interference with denning pack-ice unlikely, wide dispersion dens means population-level impacts new may be minimized by aggressive management human activities. However, because apical predators arctic marine ecosystem, also among first mammals to show effects broad-scale environmental changes such as global warming, can adversely affect populations even when local adequately managed. biological potential recover from any perturbation low their reproductive rate. Hence, maintain present favorable situation, knowledge status must kept current challenges met head-on. Spatial temporal restrictions activity prevent being disrupted but vigilance mandatory a relatively optimistic outlook.