Not too long ago, I wrote a blog post about the Labynkyr Devil, a Siberian lake monster with a long history. I found the following report of which gives us a clue about the creature’s diet:
A couple of other carnivorous water cryptids come to mind. The Bear Lake Monster, which began to be widely reported in the late 1860s, was thought by the Shoshone people to have died after a harsh winter in 1830 killed off much of the buffalo—its preferred food source. The Manguruyu, the giant catfish of the Gran Chaco, has been observed snatching dogs by the indigenous people in Paraguay. I wrote a blog post about the “Soviet Serpent” in lake Kol-Kol, in Kazakstan, which preys on livestock such as goats that venture too close to the water.