Blue whales are endangered species because of chemicals, contaminants, and spilled oil that pollutes the water. Their food is one cause for their long lasting lives. It also may reduce longevity and reproduction. Moreover the shipping causes a lot of deaths; whales are run into the ships.
The threat for the whales consists in the fact that they entangle in the fishing nets. Commercial whaling is the first cause of the extinction, because the hunters kill the whales for their bones, oil and meat. That is why nowadays the population of whales is less than 5000 specimens.
On the other hand some people are worried about this problem and they have made organizations that take care of the rights of the whales. They are creating laws that protect these animals and making people aware of this problem as well as asking support from the governments to protect these animals.
In my opinion, all of us should be conscious about our planet and all the living things in it. Because if we continue destroying and polluting like we do, in a few years not only will the whales be in danger but also human beings will be facing this danger of extinction. If we continue as we are, we will end up killing everything.