The given image introduce information about population changes in three types of mammals between 2011 to 2016 in North America and next to it places.
Overall, the most significant rose connect to the bears, while dolphins decreased over the period, and the least changes come to the whales. So, at the start of the period, animals were ranged from the most biggest population to less, where dolphins were on the first place, whales on the second, and bears on the third. However, after years their places have been found reverted.
In detail, starting from 2011 , the bears population were accounted at about 10 thousands, but then it has considerably grown. So, in 2016 , their numbers peaked at unbelievable 180 thousands. As regards whales , their trends in all way were fluctuated. In addition, their popularity was the same at the first and the last years and were recorded at around 70 thousands. In respect to the dolphins, they have smoothly declined graphic that in 2011, population were noted at 150 thousands. Subsequently, the fact that can be unfortunate, their numbers were broken the bottom and there there is not a single dolphin left.