If you refer to a particular type of population in a country or area, you are referring to all the people or animals of that type there.
双语例句
例： 75.6 per cent of the male population over sixteen.
16岁以上男性人群的75.6％
例： areas with a large black population.
有大批黑人群体的地区。
例： the elephant populations of Tanzania and Kenya.
坦桑尼亚和肯尼亚的大象种群。