WEBVTT

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[music fades in] Pay attention to what's about to happen
with this approaching bald eagle.

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The ravens may not yet notice it, but as you and I can see,
they're about to,

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and when they do, we'll get some important insight into
the social behavior of this iconic bird.

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[slow music playing]

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Let's pause here for a moment.

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The ravens are eating at the carcass of a bison, which likely
died sometime during the winter and is now

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thawing out to become a meal for a host of scavengers.

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A carcass like this can attract and feed a variety of animals,
from relatively small birds like ravens

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to large-bodied mammals like grizzly bears.

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Because of this, a strict social hierarchy is enforced
at a carcass.

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This bald eagle, twice the size of the ravens, is given
priority by the smaller birds.

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The eagle is able to take the meaty portions of the carcass
while the ravens are left with the rest.

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But what about when another eagle wants to feed on
the carcass?

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Let's pause again. Despite being around the same size,
the eagle on the left is able to confidently chase away

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the eagle on the right with a show of aggression, and the
eagle on the right concedes priority to the eagle on the left.

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The reason for the eagle's aggressive behavior lies in
a visible cue it sees in its opponent.

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Take notice of the difference in plumage, or feathers, between
the two birds.

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They're both bald eagles, but the eagle on the right lacks
the characteristically white head of the eagle on the left,

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indicating that it's not a mature adult eagle.

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The feathers on the head of a bald eagle don't become
white until it reaches 4 or 5 years old.

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The mature adult eagle is more experienced, and with this,
is able to act with more aggression in its defense of the carcass.

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Eventually, however, with this hierarchy established,
the younger eagle is able to feed on those portions of the

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carcass that were previously occupied by the ravens.

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It's a delicate social balance between animals of different
species and even between those of the same species.

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It's a good reminder to you and I that when interpreting wildlife
behavior, we must account for the importance of age

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and social status in animal interactions. And until next time,
remember that things aren't discovered by being seen,

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but by being noticed.

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[slow music plays]

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[music fades out]