How Bruce The Half-Beak Kea Weaponised His Disability To Become The Alpha Bird

Ximena
Nelson, University
of Canterbury

Bruce the kea is
missing his entire upper beak. Yet he is the alpha bird of
his circus (the apt collective noun for a group of New
Zealand’s famously
playful alpine parrots).

As our latest research
shows, Bruce achieved his alpha status not despite his
disability, but because of it.

In a remarkable
example of behavioural innovation, he has developed a novel
technique to fight his opponents.

Bruce
essentially weaponised his disability by using his sharp
lower beak to joust other kea, propelling himself forward
with such vigour that he nearly topples over, but not before
the other birds jump back in a flurry of orange and green
feathers.

Like other kea, Bruce will also kick to
establish dominance, but the other birds simply can’t
match his secret weapon because their intact upper beaks
curve over the bottom beak, rendering this spear-like weapon
unusable.

It is his jousting behaviour that has
enabled Bruce to win every one of his contests and become
the undisputed king of the circus.

So effective is
this novel behaviour that Bruce seldom has to fight, making
him more relaxed than the other birds over whom he reigns
supreme.

Bruce’s origin
story

In 2013, Bruce was found in the mountains of
the South Island of New Zealand – the kea’s usual
habitat. Missing his upper beak, he was brought into
captivity at Willowbank Wildlife Reserve in Christchurch
where it was believed he would have a better chance of
survival.

Bruce was so small he was initially
mistaken for a female and called Kati before genetic testing
revealed he was male. How he lost his beak remains a
mystery, but Bruce has used the intelligence
for which these parrots are known not only to survive,
but thrive.

We studied the dominance hierarchy of
12 captive kea at the wildlife reserve by observing all
aggressive encounters between the birds, and measuring who
displaced who and how often.

As is typical of kea,
this circus is not a linear hierarchy, but rather one with
some fluidity about ranks – except for Bruce, who never
lost a fight and had sole access to food at feeding time,
with other birds only coming in to eat once Bruce had his
pick.

Curious about how stress hormones
(corticosterone) mapped onto the circus hierarchy, we
collected faeces from all birds and found that Bruce,
contrary to our predictions, had the lowest level.

This was possibly because he was so dominant he
simply did not need to scrap for position as much as the
other troupe members.

Behavioural
innovation

The beak of a parrot is like a third
limb. It is used to dig for food, to climb, to grasp objects
and to pry things open.

Without an upper beak,
Bruce‘s disability should put him at a disadvantage. But
necessity is the mother of invention and Bruce has developed
many novel behaviours to compensate for the loss.

He uses sharp stones he carefully selects from
within his enclosure as tools
to help preen himself. Being the alpha male, he also
solicits and receives grooming from subordinate males. This
includes them carefully cleaning out food stuck in his lower
beak.

Instead of masticating with his upper beak,
Bruce also uses rocks, fence posts, human feet and any
number of handy objects in his enclosure to grind food to a
fleshy edible pulp.

Animal minds have much to
teach us

Kea don’t typically use tools in
nature, but they are known to be exceptional
problem solvers, comparable to primates. This is
possibly because they need to find food such as tubers
buried underground or dig for grubs in rotting logs.

It is this very attribute
of cleverness that suggests well-meaning humans who
might otherwise attach a prosthetic to a disabled animal may
actually be doing them a disservice. Bruce’s disability
has forced him to overcome problems and flourish in doing
so.

Perhaps the ability to innovate behaviours is
restricted to animals with complex cognition and the
capacity to overcome a disability through invention may be
limited to very smart species.

However, recent
research shows many animals – including a
cow named Veronika that uses a stick to scratch herself
– astonish us in developing new behaviours. I would not be
surprised if we have further revelations ahead, not only
from Bruce the kea or Veronika the cow, but from many
animals, including bumblebees
and possibly other invertebrates.

Ximena
Nelson, Professor of Animal Behaviour, University
of Canterbury

This article is
republished from The
Conversation under a Creative Commons license. Read the
original
article.