Marine biology gannets, and auks. Although they spend most of their lives in the ocean, species such as gulls can often be found thousands of miles inland. There are five main types of marine mammals, namely cetaceans (toothed whales and baleen whales); sirenians such as manatees; pinnipeds including seals and the walrus; sea otters; and the polar bear. All are air-breathing, and while some such as the sperm whale can dive for prolonged periods, all must return to the surface to breathe. Marine habitats can be divided into coastal and open ocean habitats. Coastal habitats are found in the area that extends
Whaling in Japan of extinction within a few decades according to IWC population estimates. In Japan, not only humpback, minke, and sperm whales, but many other smaller toothed whales, including species such as western gray, the endangered North Pacific right, and northern fin whales have been targets of illegal captures utilizing harpoons for dolphin hunts or intentionally drive whales into nets. Reports are later filed with administrative organs or research institutions as cases of "entanglements where fishermen tried their best to save whales". Products from internationally protected species' meat can also be found on markets even today mostly originating as "by-products" of entanglements,