American Eagle
Video: Sibling Rivalry

It’s called Cain and Abel syndrome. On a farm in Minnesota, a mother bald eagle feeds her newly hatched eaglets. The four-day-old female eaglet has turned on her smaller, two-day-old male sibling. Every time the mother feeds them, the older eaglet gets much more to eat. Her younger brother may not be able to hold on to life for long.

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  • Warriorjd

    Wow! Those eagles are as bad as humans!

  • Scott

    When eaglets hatch (a clutch of 2 is normal), they hatch from 1 to 3 days apart, in order that the eggs were laid. for the first couple of weeks, there is a visible difference in size, but past 2 weeks, the size difference starts to equal out.

    Also, bald eagles are dimorphic in the fact that the females are larger on average than males, so that gives them a little bit of a size advantage, even as nestlings. A female adult can be about a third bigger than a male.

    If the little guy can make it past a couple weeks, he should be OK.

  • Toni

    Last year at Fort St. Vrain Station here in Colorado there were 3 eaglets, when the 3rd one had hatched I was cheering ‘him’ on because he wasn’t able to get around well for a while and the other 2 were getting about all the food, I wasn’t sure if he was going to make it. At times I thought he didn’t. But he did, they all did. Towards the end, just before they were old enough to fledge, they even survived a tornado in the area. It was great watching them grow via Xcels’s webcam. This year again there is a clutch of 3. And we wait to see what happens.

  • dale

    when do eaglets hatch

  • Anuran Kar Gupta

    Fantastic study!

  • Black

    stupid female bird, it steals food from its mothers mouth when the mother is trying to give it to the little bird, its like stealing from the poor and eating it!

  • Alvin

    This is amazing! The chicks do it out of survival; humans don’t!

  • Lindsey

    Fantastic video. Was not aware of the Sibling Rivalry, Very interesting!!! I Love these Eagles they are so beautiful!!

  • lisa

    Very intresting, i am currently watching the nest in Iowa. I get down when i see the first born get all the food and the 2nd born little to none. This gave me hope it will be ok. We r still waiting for the third to hatch.

  • Deanna

    I have been mortified too by the older chick taking the other one by the head feathers and shaking it side to side. I’m calling it very bad names! : ) But I am comforted in the fact that this pair has successfully pledged several clutches successfully.

  • jhon

    Very beatiful, i like the eagles ciencia y tecnología
    avances tecnologicos

  • sara

    its really sad but its more sad when its happen with human

  • ขายเครื่องเสียง

    Monitored throughout. You very much.

  • Kate

    i love eagles!!!! they are so cute.

  • Susan

    I am curious why life was designed this way regarding the difference between hatching times of siblings and the resulting inequality of attention. The first eaglet gets the lion’s share and the second has to work so much harder at surviving insult and/or injury from the older sibling. It’s not very much unlike human behaviour, except that the parent will (hopefully) correct the older sibling. Does anyone have an idea why things may have been designed this way?

  • Susan FL

    This is a hideous side of nature! Larger babies blocking the smaller ones from being fed…Mom or Dad doing nothing to intervene!

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