雅思阅读精选：旷野的屈服非洲狮数量锐减_雅思英语阅读

雅思阅读精选：旷野的屈服非洲狮数量锐减

　　Scientists estimated that 50 years ago, approximately 100,000 lions made their home in Africas iconic savannahs. This estimate was made using rough calculations of the size of remaining habitat and lion density. Our research suggests that lion populations have experienced a dramatic decline, and numbers have dropped to as low as 32,000 individuals. We compiled all of the most current available estimates of lion numbers and distribution continent-wide reports, country-specific lion conservation strategies and action plans, and newly published lion population surveys. To fill in any gaps, we drew from the knowledge of the co-authors and colleagues working across Africa to conserve lions.

　　Lion cubs surround a patient lioness, nipping and playing, Londolozi private game reserve, South Africa. National Geographic photo by Chris Johns.

　　Counting carnivores is a tricky business. Individual identification is a tremendous challenge and requires high-resolution cameras or good, unobstructed views in person. They are often shy and cover large distances. Lions are difficult to count even though they are social and sleep most of the day. Only a very few lion populations are known at the individual level, such as Liuwa Plains National Park, Zambia. Individual recognition of every lion in an area requires intense study, significant resources, and low numbers of individuals. Therefore, researchers use a variety of other imperfect techniques to estimate lion population size in all other lion areas. Some more common estimation techniques include spoor tracking or call-up surveys.