The global warming of the Arctic, the reduction of the Arctic sea ice cover, as a result of climate change, significantly affects the representatives of the walrus and polar bear populations. Anthropogenic factors play a leading role among the causes of global warming.Changes associated with climate warming affect all elements of the ecosystem, while the impact may vary depending on the species and population. The main ones include: a decrease in the thickness and area of the ice cover and changes in the ambient temperature, migration, changes in the food chain food supply, predators, competitive species, the emergence of new infectious and invasive diseases, changes in the behavior (phenotype, genotype) of animals, which can have a huge impact on individual populations, so it is for the species as a whole. It is necessary to take into account the peculiarities of changes occurring in the populations of walrus and polar bear due to global climate warming and take timely measures to preserve these species of animals in the face of the threat of a decline in their populations.