Fiercest birds make the best home decorators

Jan 20, 2011
A Black Kite flies over in New Delhi in 2007. By examining 127 nests of the birds of prey in Spain's Donana National Park, researchers reported in the journal Science that the strongest birds showed their ferocity by decorating their homes with lots of bits of white plastic.

You might raise your eyebrows at their choice of material, but you wouldn't want to pick a fight with a black kite whose nest is adorned in white plastic, Spanish researchers said Thursday.

By examining 127 nests of the birds of prey in Spain's Donana National Park, researchers reported in the journal Science that the strongest birds showed their ferocity by decorating their homes with lots of bits of white plastic.

And only white would do, said scientist Julio Blas of the Spanish National Research Council.

"The amount of decoration is related to the fighting ability of the individuals," Blas said.

Birds of prime age, seven to 12 years old, tended to use the most .

"They prefer plastic, and they specifically prefer white plastic which makes the nest more visible not only to humans but to other kites."

The extra decor, which tended to accumulate about 20 days before the female laid her , seemed to invite more clashes with other aggressive, highly territorial birds.

But those who showed the most white plastic in their towering branch nests were "also found to be the most capable of defending their territory from intruding black kites," said the study.

As an experiment, researchers tried attaching white plastic to the nests of younger and older , and found that black kites who were not in top fighting shape quickly removed it.

"This could be similar to the use of different colors for the belts of judo or karate fighters," said Blas.

"You don't want to have a color that doesn't match with your fighting capability because you won't get any benefit from it."

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User comments : 10

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Blakut
not rated yet Jan 20, 2011
Um, maybe because in nature the birds would put bones on their nest, to show how many critters they killed, and so, how strong they are? Bones are white...bits of plastic may look like bones form tiny animals.
Djincs
not rated yet Jan 21, 2011
No no no, the thing here is that 20 days before laying eggs they decorate, it is white like the eggs, so when another bird see them it comes for them and then the parents kick ass, when the eggs are layed(the other birds cant say is there eggs or not-the point of plastic being white) then they wont come back again(why their ass to kicked again), and the chance of survival of the eggs(if there is no parent at the moment to protect them) improves, if the parents cant kick ass then there is no point of doing it, they will bring atention only to sholl they cant cope with the intruders.
I made this up now but I think this is the case.
Djincs
not rated yet Jan 21, 2011
And actually somethimes i wonder how little naturalists understand the nature and the animals:

"This could be similar to the use of different colors for the belts of judo or karate fighters," said Blas.

"You don't want to have a color that doesn't match with your fighting capability because you won't get any benefit from it."

Come on no logic in that!
Skeptic_Heretic
not rated yet Jan 21, 2011
"This could be similar to the use of different colors for the belts of judo or karate fighters," said Blas.

"You don't want to have a color that doesn't match with your fighting capability because you won't get any benefit from it."

Come on no logic in that!
There's perfect logic in that. If you were going to be forced into a fight, who would you rather fight, the guy covered in prison tatoos or the guy without?
If the guy without prison tattoos goes and gets a few, does that make him tougher? Nope. But now he's wearing a tough guy's skin. He may get in fewer fights, but if he does get in one, he's going to get stomped.
Djincs
not rated yet Jan 21, 2011
Now like the judo thing you put some sick logic.
Why they choose white?
Why 20 days before laying eggs?
When a bird see something white in the nest there are two options-eggs or hatched eggs=easy meal-no tatoos no judo ranking, it is a bird!!!
If it show rank it will be allways there, and if it works the others will bluf.
GSwift7
not rated yet Jan 21, 2011
They talked at length about this one on NPR yesterday. They had the guy from the story above, and then they had another biologist afterwards who said he didn't agree with any of this. He actually used the phrase "I'm not buying it". His explanation was actually what you said Djincs. He thought that the level of self-awareness that it would require for these birds to make that kind of decision about how tough they are isn't likely.
Skeptic_Heretic
not rated yet Jan 21, 2011
Why they choose white?
Why 20 days before laying eggs?
When a bird see something white in the nest there are two options-eggs or hatched eggs=easy meal-no tatoos no judo ranking, it is a bird!!!
Well I read your idea, doesn't seem bad. To me it's more about attracting a mate.

As you said, white sticks out. Says "Hey ladies, I'm open for business." The best mates have the most white plastic, and as such, stick out the most. Especially where the Black Kite isn't exactly a flashy bird, this very well could be a learned behavior due to sexual selection.
Djincs
not rated yet Jan 21, 2011
They talked at length about this one on NPR yesterday. They had the guy from the story above, and then they had another biologist afterwards who said he didn't agree with any of this. He actually used the phrase "I'm not buying it". His explanation was actually what you said Djincs.

I am glad there are people using their heads, I dont know why but they piss me of somethimes, they have studied them whatched them and talk shits.....and get paid for that-maybe that is what pisses me of!
Djincs
not rated yet Jan 21, 2011
"He thought that the level of self-awareness that it would require for these birds to make that kind of decision about how tough they are isn't likely."

Well actually i beleave this. I think the bird is capable of knowing where it stands- at the top or the bottom, ierarhy is everywhere even among non hurdal animals.And it is just an instinct , they dont think logical ofcource. If they feel powerful they will do this.....maybe the guy from the tv were determined to totaly destroy the previos guy , but i beleave what they have observed because it make sence.Interpretation is bad.
GSwift7
not rated yet Jan 24, 2011
I don't know. I was just repeating what they said. NPR is national public radio, not television.

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