Humans have been observing Orcas for a tiny sliver of their existence. Orcas discovering a major new behavior just when we happen to have the means of observing them seems breathtakingly unlikely.
i wouldn't be so sure of that. of course just because we witness doing them something for the first time doesn't mean that is their first time doing that thing, but the mammal-eating orcas are rather adaptable animals are obviously extremely intelligent. due to receding ice barriers, orcas are now eating beluga whales, stealing from polar bears, which is a previously unknown prey for them. also, orcas were well known to be aiding fisherman and whalers in australia with documented cases of herding whales into a bay. even today, fisherman have been noted as witnessing increasingly new behavior in orcas tracking down fishing boats to steal their catches. whales off the coast of south africa also eat great whites, and they also chase down dolphins, including massive feeding frenzies off the huge (like 1000+) dolphin herds there. it is not clear when this behavior started, but orcas do not typically eat dolphins.
orcas also have other behavioral techniques that are very human-like. off the coast of canada, there are orcas who visit a specific shallow area to receive a massage off of the smooth pebbles there.
so i would say it's breathtakingly unlikey that orcas are not learning new techniques all the time.
It seems unlikely that they've just learned that behavior in the ~200 years we've been observing them scientifically
https://www.youtube.com/watch?v=g1VEwsI4SlY
And better (but long):
[0]https://en.wikipedia.org/wiki/Killer_whales_of_Eden,_Austral...
I'll have a look for a source if I can later.
In all fairness, humans have discovered many major new behaviours in that same time period.
Obviously true. But in fact the dolphin family (of which orcas are the largest member) branched off of toothed whales only about 10M years ago, making them only a little bit older than hominids. We're both pretty recent arrivals.