Marine Mammals – Part 3

The killer whales belong to the oceanic dolphin family and are highly social. May be like our Mamis? Read on and then you can’t stop admiring them, I mean the killer whales! 

The MB showed the photograph of 137 and pointed at the killer whale. The picture had a curved dorsal also had a distinct fluke. She explained to us the distinct color patches: black back, white chest and sides, and a white patch above and behind the eye and how they can be recognized from their dorsal fin and tail fin.

They are indeed a chatter box
The killer whales like to communicate and depend heavily on underwater sound for orientation, feeding, and navigation. They produce three categories of sounds: clicks, whistles, and pulsed calls. Clicks are believed to be used primarily for navigation and discriminating prey and other objects in the surrounding environment, but are also commonly heard during social interactions.

Males are momma’s boy for life
Killer whales are notable for their complex societies. Only elephants and higher primates, such as humans, live in comparably complex social structures. Males live with their mothers for their entire lives. These societies are based on matrilines consisting of the matriarch and her descendants who form part of the line, as do their descendants. The average size of a matrilineal is 5.5 animals. The killer whales are also found to adopt orphaned calves and care for them throughout their life. Because females can reach age 90, as many as four generations travel together.

No incest in their world
Males separate for only a few hours at a time, to mate or forage and come back to their mothers. Closely related matrilines form loose aggregations called pods, usually consisting of one to four matrilines. Unlike matrilines, pods may separate for weeks or months at a time. DNA testing indicates resident males nearly always mate with females from other pods.

Activities in water
The killer whale activity consists of foraging, travelling, resting and socializing. Killer whales are frequently active at the surface, engaging in acrobatic behaviors such as breaching, spyhopping, and tail-slapping. These activities may have a variety of purposes, such as courtship, communication, dislodging parasites, or play. Spyhopping, a behavior in which a whale holds its head above water, helps the animal view its surroundings.

 

But they are apex predators
These whales are regarded as apex predators and feed on salmons and other varieties of fishes. They also go for mammals such as sea lions, seals, walruses, and other smaller whales in the pyramid. There have been a few instances where they have tried to kill humans.

They are intelligent too
They are also regarded as the most intelligent species among marine mammals. Killer whales imitate others, and seem to deliberately teach skills to their kin. Adults sometimes pull seals off the shoreline, and then release them again near juvenile whales, allowing the younger whales to practice the difficult capture technique on the now-weakened prey. The killer whales use dialects and pass on other learned behaviors from generation to generation, thereby forming a culture.

Yet their population is shrinking
They may be apex predators in the marine ecosystem, but we are sitting on top of them in the ecological pyramid and creating havoc to their world. Pollution from large-scale oil spills, letting in untreated sewage, chemical leaching, and disturbance caused by noise and conflicts with boats are currently the most significant worldwide threats to the marine mammals. The impact of sonar waves on killer whales is potentially life-threatening.

I don’t care even if we don’t have such rides along our coast, but atleast let us not pollute their world and kill them for food and other monetary gains.