Narrow shave while out fishing this past week for Fjörgen's dinner; or at least I think it was a close shave. I ran into a pod of orcas; big buggers they were, at least eight metres long and fat as hell! We call them, minke hunters, after the minke whales that are their primary target. Fortunatey they didn't seem to be particularly interested in me; perhaps they sought a more substantial meal than one dozy emperor who has a habit of not looking where he's swimming. And that got me to thinking as I made my way back to the rookery.
There are rumours, gossip, within the scientific community, at least among those who study cetaceans, that we could be heading down the road of speciation for orcas; at worst they might divide them up into distinct races. You see, there's a funny (odd not amusing) fact about orcas that you might not know. (I, on the other hand do know; I have to keep my ear to the ice when it comes to potential predators.)
You see, orcas seem to have quite individual hunting styles depending on where they normally feed. The pods in a particular range- area of the ocean seem to have particular preferences for food and particular hunting tactics for ultimately catching their usual prey. They also appear to have quite distinct regional dialects in their calls and, possibly by extension, their means of communication with one and another; they do range, as a species, over most of the planet's oceans and the individual pods only number a dozen or so, although many pods may quarter particular tracts of ocean.
On a particular coastline in Eastern Patagonia, the orcas deliberately chase seals almost onto the beach in pursuit, possibly as a deliberate tactic; the seals having made the shore, they then feel safe only to have a seven ton behemoth suddenly grab them from behind. The orcas then flap and squirm in the tide in order that they can get themselves out into water which is deep enough to support their weight. This seemingly takes years to master successfully. (Some dolphins, I don't know what species, have seemingly learnt this trick also.)
Other pods follow the migrating grey and humpback whales and their newborn up the eastern pacific coastline towards Alaska, ambush them and seek to divorce the calf from its mother by a co-ordinated attack and then drown the calf by submerging it.
Pods that frequent the waters of New Zealand, whose prediliction is for stingrays, have learnt the novel trick of turning the fish upside down, which induces an almost hypnotic, semi-comatose state in sharks and rays, which probably also accounts for the success of the orca in the one observed 'battle' between the two apex predators of the oceans; the orca and the great white shark. (The sperm whales could likely destroy both but it hunts deep and so does not compete.) The orca won by simply turning the great white upside down and waiting for it to fall into 'a trance'! (I think that there is a film on YouTube but don't hold me to it.)
There are also pods which hunt in the North Atlantic and the North Pacific, which have broadly similar tactics. They are primarily fish eaters, although the specific fish that they eat are not the same. They herd the shoals of fish into denser and denser melées until they cannot become any denser and then the orcas strike the shoals of fish with their tails, which effectively stuns them. The orcas can mop up at their leisure. What is perhaps strange is that the Pacific orcas seem to have a distinct 'rallying call' as they attempt to drive the shoal into maximum density, which is not mirrored in the North Atlantic pods.*
And finally, the one that I know best, because Havelock told me so, 'wave-hunting' around the ice floes where seals are to be found, catching a brief respite from the rigours of hunting fish (and penguins). The orcas swin en masse towards the floe to create a bow wave which cascades over the floe and so washes the seal out into the open water where it is easy prey.
Now, this seems to me to be learnt as behaviour; especially as Havelock tells it. He only escaped because the seal and him were put back on the flow and made to endure the terror again; the juveniles were being shown how to do it..
Now, whichever way that you look at it, to generate such a bow wave, at the very least, requires a co-ordination of effort amongst the pod members; maybe natural selection could have worked the magic to make this and all the other techniques work but is it not more likely that, like humans, the orca have learnt to communicate. Even if is it only 'whistle, whistle, squee, hum', "do as I do until you produce the same result'.
It is this fact which makes me undisposed to assigning different species to the various populations around the globe; the orcas are behaving like humans. They educate and care for their young; even, in some instances, their deformed adults, and they communicate a culture to those young, however basic, rudimentary or primitive it might be. They might have diverged genetically from each other, as human being might one day, if you are given the length of time that orcas have,, around 700,000 years but it appears clear to me that orcas have gained their place as supreme 'not-deep' water predators due to their acquired intelligence; not Mother Nature.
PS Is that perhaps why they couldn't get a pod to accept Keiko, the captive orca; he just didn't speak their language? How would you in Iran be accepted if you didn't speak Iranian
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