Orcas (orcinus orca) are one of the most successful, long living hunters and the largest apex predator in the ocean (Coscarella, A., et al, 2015) and are subsequently able to hunt a variety of different prey. Orcas, often referred to as killer whales, can be found all over the world and as a result the many different pods have all evolved different ways of hunting adapted to help them to feed on prey specific to their locations.
The reason for these different hunting methods have not been fully researched by scientists yet but they could have happened for multiple reasons, however the two most known factors I believe could be due to the fact that hunting methods are passed down from generation to generation, meaning that any calves born will be taught to hunt by the previous generation and will be taught specific hunting methods that have been perfected through the years to capture prey animals in the pod’s hunting grounds. The second reason could be that due to the fact that pods remain together for their whole lives they often develop their own dialects and behaviors which mean that one pods will different from almost every other pod in the world in some way.
This behavior can be seen in locations such Patagonia where orcas where one pod of orcas were documented having devised a hunting method of intentional stranding whilst hunting marine mammals like sea lions and elephant seals on beaches (Coscarella, A., et al, 2015) this is especially helpful for orca to catch younger less experienced pups that think reaching land will save them from further predation. Another example of this behavior is shown in Antarctica where seals being hunted by orca have the added protection of floating ice pockets which allow them a reprieve from the orcas, however the orcas have adapted ways of combatting this protection by swimming below the ice and using their powerful flukes and pod co-ordination to swim below the ice and create waves that will cause either the prey to fall off or the ice pocket to flip over and force the prey back into the water and in reach of the orca.
Even though the reason for these differences between hunting methods have not been fully researched and definitive answer reached many people believe that due to this difference in pods almost like different families and cultures around the world, orcas have like people evolved over time to become specialized in their environments which each present different challenges for them to overcome which they in turn teach the next generation ensuring the continuation of theirs highly specialized hunting methods.