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Re: In the news: Southwest Alaskans say bird is the size of a small plane
Allan Edels wrote:
> Anyway, any guesses as to what they really saw (NOT the guy from 1944!):
> A giant (world record sized) Steller's Eagle?
Speaking as a professional land surveyor, chances are they just saw a
regular sized bird of whatever species and misjudged the distance to
it. Missing the distance by 50% doubles or halves the apparent size of
the bird, and very few people can judge long distances accurately. With
no visual cues for reference, no one can if outside the range for
steroscopic vision (which only works for very short distances anyway).
I work with distances and elevations professionally, and cannot estimate
them within 25% without visual references to assist in making the
judgement. For example, consider the 'large moon' illusion seen when
the moon is near the horizon. Very few of us think the moon is actually
larger or closer then than when near the zenith. As total speculation,
perhaps they saw a misplaced Wandering Albatross (11 ft wingspan) and
underestimated its distance by 20-25%. Presto, one perceives about a 14
foot span. The same holds for an eagle (or a hummingbird) if one
misjudges the distance by a bit more.