amazing photos from California shows an example for one animal riding on another. It is a crow nestled on a flying eagle's back. From the photos you can see that the crow was likely looking to do more than catch a lift.
In fact, birds are considered very territorial. This is commonly during the summer when their hatchlings are vulnerable. For instance, crows (and many birds) seem to have a Napoleon complex—the mere presence of a larger bird incites heckling and mobbing. McGowan says territorial birds often don’t normally get too close, however this particular crow probably found itself in the eagle's draft and settled in for the ride.
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