It is said that the owl brings misfortune and pessimism, and that the turtle brings goodness. Is there any evidence for this or is it superstition?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

There is no evidence for what the questioner said that the owl brings misfortune and pessimism, and that the turtle brings goodness, rather this is a superstition and a deviation in creed; and it is feared that whoever believes in this is committing an act of disbelief. It is confirmed that the Prophet said: "Seeing a bad omen is Shirk (disbelief)." [Abu Daawood, An-Nasaa’ee, At-Tirmithi and Ibn Maajah]

Seeing a bad omen is being pessimistic about something and it is a practice of the people of the pre-Islamic era. All matters are in the Hands of Allaah, and the owl or the turtle does not have any role in this.

Allaah Knows best.