Six rare right whales died in one month. The species has only about 400 right whales left. They often collide with fishing ships or become entangled in fishing nets. Right whales migrate following food sources. Despite awareness and protection, the population hasn’t fully rebounded.
https://www.huffpost.com/entry/six-right-whales-killed-canada_n_5d1ee522e4b0f31256815b3a