Snow bugs are often seen in autumn before the long winter in Hokkaido. In Hokkaido, it is said that the first snow falls when snow bugs fly, but "Yukimushi" is not its official name. What exactly are they? We also investigated whether "the first snow falls when snow bugs fly" is true.

The true identity of the snow bug is the "Steller's sea lion weevil.

Snow bugs are actually a type of aphid called "Steller's sea lion weevil. As an adult, it is covered with waxy white hairs and flies in a fluffy manner, giving rise to the name "snow bug" as it "looks like snow.

The Abies sachalinensis is born in the spring in a tree called Yachidamo, and takes up residence in Abies sachalinensis in the summer and early fall. While sucking sap from the Abies sachalinensis tree, they change generations several times during the year, and at the end of the fall, the winged adults migrate to the Yachidamo tree. In other words, what we were seeing was the adult Abies sachalinensis snow beetle on its way from Abies sachalinensis to Yachidamo.

An unusual survival strategy unique to a weak insect.

Abies sachalinensis is known as a "weak insect," having no way to resist foreign enemies and being preyed upon rapidly. However, a major characteristic to counteract this is its "stem mother" morphology.

One female produces about 150 larvae, so they have been able to survive until now by continuing to produce more larvae even while being preyed upon. This is why they have survived until now.