Toothed whale swallow fishing hooks. Gillnetting and Seine netting are significant causes of mortality in cetaceans and other marine mammals. Porpoises are commonly entangled in fishing nets. Whales are also affected by marine pollution. High levels of organic chemicals accumulate in these animals since they are high in the food chain. They have large reserves of blubber, more so for toothed whales, as they are higher up the food chain than baleen whales. Lactating mothers can pass the toxins on to their young. These pollutants can cause gastrointestinal cancers and greater vulnerability to infectious diseases. They can also be poisoned by swallowing
Greater white-toothed shrew and migration to empty breeding sites. Nonetheless, this dispersal pattern is a preventative measure for inbreeding. The greater white-toothed shrew can be very vocal."C. russula" can find their way around their environment via a primitive form of echolocation where they produce a high pitched twittering call to interpret their environment. The use of this laryngeal call and vibrissae allow the shrews to find their way around their environment. There have not been any concrete reports on the modes of communication used by this species,however, the vocalization and tactile and chemical cues likely to be used. The greater white-toothed shrew typically