They are valid

Backstory, quoted from wiki:

"The skvader originates from a tall tale hunting story told by a man named Håkan Dahlmark during a dinner at a restaurant in Sundsvall in the beginning of the 20th century. To the amusement of the other guests, Dahlmark claimed that he in 1874 had shot such an animal during a hunt north of Sundsvall.

On his birthday in 1907, his housekeeper jokingly presented him with a painting of the animal, made by her nephew and shortly before his death in 1912, Dahlmark donated the painting to a local museum.

During an exhibition in Örnsköldsvik in 1916 the manager of the museum became acquainted with the taxidermist Rudolf Granberg. He then mentioned the hunting story and the painting and asked Granberg if he could re-construct the animal. In 1918 Granberg had completed the skvader and it has since then been a very popular exhibition item at the museum, which also has the painting on display."

Source: https://en.m.wikipedia.org/wiki/Skvader