Are humpback whales really vigilante sea beasts
that guard the world from killer whales?
A pod of killer whales in Antarctica has a
seal cornered on an ice floe.
Just as they knock it off and close in for
the kill, a humpback whale
bursts upward beneath them.
It uses its flippers to hold the seal on its
upturned belly, keeping it out of the water
until the predators leave.
We all love it when someone stands up to a
bully.
There’s records of humpbacks saving all
kinds of animals from killer whales, including
sea lions, sunfish, seals and gray whales.
But are they doing this intentionally?
Are humpbacks the superheroes of the sea?
The marine ecologist who saw the humpback/seal
scenario I described is Robert Pitman, and
his team has published a new study in the
journal of “Marine Mammal Science” that
takes a closer look at what’s going on here.
An adult humpback is so enormous that it’s
pretty much invulnerable
to a group of killer whales.
And when it gets in the middle of a brawl,
it uses its massive pectoral flippers to basically
say, “Aw hell no. Step back son.”
They slap the water and bellow, pushing the
killer whales back.
This “mobbing behavior” is a response
we also see in birds, insect, fish and other
mammals to chase off potential predators.
Humpbacks have foiled killer whales everywhere
from Antarctica to the North Pacific.
Sometimes they even work in pairs and will
travel over 2 kilometers to ruin a killer
whale hunt.
They’ve been observed to keep fighting for
up to seven hours, until the prey can escape.
The team’s research looked at 115 documented
interactions between humpbacks and killer
whales, from 1951 and 2012.
They found that they almost exclusively went
after “mammal-eating” killer whales, instead
of those that just eat fish.
We’re talking more like the 1977 horror
movie “Orca”
than we are “Free Willy” here.
And while humpbacks do mob killer whales attacking
their own calves, 89% of the time they’re
saving other species entirely.
So why are humpbacks doing this?
They’re not known to mingle with these other
species in other circumstances.
Pitmans’ team thinks the humpbacks are drawn
to the scene by the sounds killer whales make
during their attack.
There’s three possible motivations driving this
behavior: 1) a proactive warning to killer
whales not to mess with their kin, 2) altruism…
or 3) pure revenge.
Since killer whales do attack young humpbacks,
it’s possible that the adults respond to
all attacks with extreme prejudice.
But humpbacks are capable of sophisticated
thinking and communication.
So it’s plausible they’d display a regard
for other species.
Dolphins do. And so do we… sometimes.
But what if it’s simply humpback reciprocity
for past killer whale attacks on their family?
Remember the shark in “Jaws 4: The Revenge?”
Like that, except for instead of chasing Michael
Caine they’re after killer whales.
Or maybe we shouldn’t try to interpret their
behavior through human experience at all.
There’s more research to be done, and even
Pitman contends that this behavior may unintentionally
arise out of self-interests we don’t understand
yet.
I for one look forward to the day I can ride
a humpback named Mer-Max into battle.
But why do you think humpbacks are throwing
down with killer whales?
Let us know.
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and more,
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