Whale 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 litter, such as plastic bags. Advanced military sonar harms whales. Sonar interferes with the basic biological functions of whales—such as feeding and mating—by impacting their ability to echolocate. Whales swim in response to sonar and sometimes experience decompression sickness due to rapid changes in depth. Mass strandings
Michael Bigg key discoveries of Dr. Bigg's team was that there were two types of killer whales living near the British Columbia coastline: "residents" which ate almost exclusively fish, and "transients" which hunted marine mammals and other warm-blooded prey. Resident and transient killer whale societies are separate, and the two types tend to avoid each other. The resident killer whale population of British Columbia and Washington is further divided into two "communities", one northern and one southern, that do not interbreed. Another discovery was that resident killer whales have one of the most stable social structures of any animal species. Pods of