Wolves howl to communicate over long distances. It is a way of saying “here I am” to the rest of the pack or “stay away” to intruders.
There is no indication that the Moon phase plays any particular part in the wolf’s calls, but wolves are nocturnal animals, so they are generally more active at night. Wolves do howl in the direction of the sky because projecting their howl upward carries the sound farther.
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