Pinniped High levels of organic chemicals accumulate in these animals since they are near the top of food chains and have large reserves of blubber. Lactating mothers can pass the toxins on to their young. These pollutants can cause gastrointestinal cancers, decreased reproductivity and greater vulnerability to infectious diseases. Other man-made threats include habitat destruction by oil and gas exploitation, encroachment by boats, and underwater noise. Pinniped Pinnipeds, commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic marine mammals. They comprise the extant families Odobenidae (whose only living member is the walrus), Otariidae (the eared
Pinniped Peninsula in 1886. Seal killings continued, and the last reliable report of the animal alive was in 1952. The IUCN declared it extinct in 1996. The Japanese sea lion was common around the Japanese islands, but overexploitation and competition from fisheries drastically decreased the population in the 1930s. The last recorded individual was a juvenile in 1974. As of 2013, the International Union for Conservation of Nature (IUCN) recognizes 35 pinniped species. With the Japanese sea lion and the Caribbean monk seal recently extinct, ten more are considered at risk, as they are ranked "Critically Endangered" (the Mediterranean and Hawaiian