They are sleeping there, because there are a lot of other people, so they are recognizing that they can sleep. They memorized that they can sleep, if more are there and not during the nights.
Sleeping swarm of swans in Dresden
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Sleeping swarm of swans in dresden free stock photo
Free high resolution images sleeping swarm of swans in dresden, bütykös hattyú, kyhmyjoutsen, 疣鼻天鹅, コブハクチョウ, تم صامت.
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Created at: 2017-05-07
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